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Document and Entity Information - USD ($) $ in Billions	12 Months Ended
Document and Entity Information - USD ($) $ in Billions	Dec. 31, 2016	Feb. 10, 2017	Jun. 30, 2016
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	FY
Trading Symbol	SPSC
Entity Registrant Name	SPS COMMERCE INC
Entity Central Index Key	0001092699
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		17,180,650
Entity Public Float			$ 1.0

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
CURRENT ASSETS
Cash and cash equivalents	$ 115,877	$ 121,538
Short-term marketable securities	23,076	7,517
Accounts receivable, net	20,746	17,615
Deferred costs	19,224	15,086
Other current assets	7,010	5,030
Total current assets	185,933	166,786
PROPERTY AND EQUIPMENT, net	15,314	13,620
GOODWILL	49,777	33,848
INTANGIBLE ASSETS, net	19,788	15,081
MARKETABLE SECURITIES, non-current	7,494	14,950
OTHER ASSETS
Deferred costs, non-current	6,086	5,260
Deferred income taxes, non-current	12,446	11,149
Other non-current assets	1,527	1,037
Total assets	298,365	261,731
CURRENT LIABILITIES
Accounts payable	2,302	2,163
Accrued compensation	13,740	11,150
Accrued expenses	3,508	1,987
Deferred revenue	11,055	7,740
Deferred rent	1,556	1,194
Total current liabilities	32,161	24,234
OTHER LIABILITIES
Deferred revenue, non-current	10,847	11,005
Deferred rent, non-current	4,179	4,307
Deferred income tax liability	1,911
Total liabilities	49,098	39,546
COMMITMENTS and CONTINGENCIES
STOCKHOLDERS' EQUITY
Preferred stock, $0.001 par value; 5,000,000 shares authorized; 0 shares issued and outstanding
Common stock, $0.001 par value; 55,000,000 shares authorized; 17,081,145 and 16,723,994 shares issued and outstanding, respectively	17	17
Additional paid-in capital	286,315	265,265
Accumulated deficit	(33,739)	(39,449)
Accumulated other comprehensive loss	(3,326)	(3,648)
Total stockholders' equity	249,267	222,185
Total liabilities and stockholders' equity	$ 298,365	$ 261,731

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	55,000,000	55,000,000
Common stock, shares issued	17,081,145	16,723,994
Common stock, shares outstanding	17,081,145	16,723,994

Consolidated Statements of Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Revenues	$ 193,295	$ 158,518	$ 127,947
Cost of revenues	64,346	50,043	39,991
Gross profit	128,949	108,475	87,956
Operating expenses
Sales and marketing	65,886	55,374	46,990
Research and development	21,981	17,954	13,494
General and administrative	28,827	24,817	20,233
Amortization of intangible assets	4,738	3,307	2,856
Total operating expenses	121,432	101,452	83,573
Income from operations	7,517	7,023	4,383
Other income (expense)
Interest income, net	601	197	187
Other income (expense), net	732	(145)	(458)
Total other income (expense), net	1,333	52	(271)
Income before income taxes	8,850	7,075	4,112
Income tax expense	(3,140)	(2,436)	(1,408)
Net income	$ 5,710	$ 4,639	$ 2,704
Net income per share
Basic	$ 0.34	$ 0.28	$ 0.17
Diluted	$ 0.33	$ 0.27	$ 0.16
Weighted average common shares used to compute net income per share
Basic	16,947	16,565	16,236
Diluted	17,241	17,032	16,814
Other comprehensive income (loss)
Foreign currency translation adjustments	$ 336	$ (2,119)	$ (1,470)
Unrealized loss on investments (net of tax of $5, $31, and $0)	(9)	(59)
Comprehensive income	$ 6,037	$ 2,461	$ 1,234

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Tax on net unrealized gains on investment securities available for sale	$ 5	$ 31	$ 0

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]
Beginning balance at Dec. 31, 2013	$ 192,773	$ 16	$ 239,549	$ (46,792)
Beginning balance, shares at Dec. 31, 2013		16,092,121
Stock-based compensation	5,396		5,396
Exercise of stock options and issuance of restricted stock	1,886		1,886
Exercise of stock options and issuance of restricted stock, shares		186,678
Excess tax benefit of stock options exercised	261		261
Employee stock purchase plan	1,338		1,338
Employee stock purchase plan, shares		26,353
Stock issued for acquisition	2,203		2,203
Stock issued for acquisition, Shares		43,595
Net income	2,704			2,704
Foreign currency translation adjustments	(1,470)				$ (1,470)
Ending balance at Dec. 31, 2014	205,091	$ 16	250,633	(44,088)	(1,470)
Ending balance, shares at Dec. 31, 2014		16,348,747
Stock-based compensation	6,379		6,379
Exercise of stock options and issuance of restricted stock	4,440	$ 1	4,439
Exercise of stock options and issuance of restricted stock, shares		346,885
Excess tax benefit of stock options exercised	2,336		2,336
Employee stock purchase plan	1,478		1,478
Employee stock purchase plan, shares		28,362
Net income	4,639			4,639
Foreign currency translation adjustments	(2,119)				(2,119)
Unrealized loss on investments	(59)				(59)
Ending balance at Dec. 31, 2015	222,185	$ 17	265,265	(39,449)	(3,648)
Ending balance, shares at Dec. 31, 2015		16,723,994
Stock-based compensation	8,023		8,023
Exercise of stock options and issuance of restricted stock	4,303		4,303
Exercise of stock options and issuance of restricted stock, shares		279,841
Excess tax benefit of stock options exercised	4,070		4,070
Employee stock purchase plan	1,732		1,732
Employee stock purchase plan, shares		33,357
Stock issued for acquisition	2,922		2,922
Stock issued for acquisition, Shares		43,953
Net income	5,710			5,710
Reclassification of losses on investments into earnings	18				18
Foreign currency translation adjustments	336				336
Unrealized loss on investments	(32)				(32)
Ending balance at Dec. 31, 2016	$ 249,267	$ 17	$ 286,315	$ (33,739)	$ (3,326)
Ending balance, shares at Dec. 31, 2016		17,081,145

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities
Net income	$ 5,710	$ 4,639	$ 2,704
Reconciliation of net income to net cash provided by operating activities
Deferred income taxes	(1,698)	(38)	1,031
Share-based earn-out liability	(1,103)
Depreciation and amortization of property and equipment	6,598	6,265	5,714
Amortization of intangible assets	4,738	3,307	2,856
Provision for doubtful accounts	1,375	1,271	717
Stock-based compensation	8,023	6,379	5,396
Changes in assets and liabilities, net of effects of acquisitions
Accounts receivable	(3,735)	(3,517)	(3,890)
Deferred costs	(4,964)	(3,023)	(4,590)
Other current assets and non-current assets	(1,911)	(2,037)	(719)
Accounts payable	(382)	(1,569)	1,271
Accrued compensation	2,180	1,295	1,568
Accrued expenses	990	(461)	1,365
Deferred revenue	2,710	587	2,440
Deferred rent	234	1,331	925
Net cash provided by operating activities	18,765	14,429	16,788
Cash flows from investing activities
Purchases of property and equipment	(8,008)	(8,757)	(7,582)
Purchases of marketable securities	(23,135)	(22,527)
Maturities of marketable securities	15,018
Business acquistions, net of cash acquired	(18,032)		(12,595)
Net cash used in investing activities	(34,157)	(31,284)	(20,177)
Cash flows from financing activities
Net proceeds from exercise of options to purchase common stock	4,303	4,440	1,886
Excess tax benefit from exercise of options to purchase common stock	4,070	2,336	261
Net proceeds from employee stock purchase plan	1,732	1,478	1,338
Net cash provided by financing activities	10,105	8,254	3,485
Effect of foreign currency exchange rate changes	(374)	(656)	(595)
Net increase (decrease) in cash and cash equivalents	(5,661)	(9,257)	(499)
Cash and cash equivalents at beginning of period	121,538	130,795	131,294
Cash and cash equivalents at end of period	115,877	121,538	130,795
Supplemental disclosure of cash flow information
Cash paid for income taxes, net	722	$ 114	113
Non-cash financing activities:
Common stock issued for business acquisitions	$ 2,922		$ 2,203

General	12 Months Ended
General	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
General	NOTE A – General *Business Description* We are a leading provider of cloud-based supply chain management solutions, providing network-proven fulfillment, sourcing and item assortment management solutions, along with comprehensive retail performance analytics, to thousands of customers worldwide. We provide our solutions through the SPS Commerce platform, a cloud-based product suite that improves the way suppliers, retailers, distributors and logistics firms orchestrate the sourcing, set up of new vendors and items, and fulfillment of the products that customers buy from retailers and suppliers. We derive the majority of our revenues from thousands of monthly recurring subscriptions from businesses that utilize our solutions. *Basis of Presentation* The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and include the accounts of SPS Commerce, Inc. and its subsidiaries. All intercompany accounts and transactions have been eliminated in the consolidated financial statements. *Foreign Currency Translation* Assets and liabilities denominated in currencies other than the U.S. dollar are translated into U.S. dollars at the exchange rates in effect at the balance sheet date, with the resulting translation adjustments recorded as a separate component of accumulated other comprehensive loss. Income and expense accounts are translated at the average exchange rates during the year. Foreign currency transaction gains and losses, if any, are included in net income. *Use of Estimates* Preparing financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates. *Business Combinations* We recognize separately from goodwill the fair value of the assets acquired and the liabilities assumed at the acquisition date. Goodwill as of the acquisition date is measured as the excess of consideration transferred and the net of the acquisition date amounts of the assets acquired and the liabilities assumed. Assets acquired include tangible and intangible assets. We use estimates and assumptions that we believe are reasonable as a part of determining the value and useful lives of purchased intangible assets and the purchase price allocation process. While we believe these estimates and assumptions are reasonable, they are inherently uncertain and subject to refinement. As a result, during the measurement period, which may be up to one year from the acquisition date, we may record adjustments to the fair value of the assets acquired and the liabilities assumed. Any such adjustments would be recorded as an offset to goodwill. Upon the conclusion of the measurement period or final determination of the fair values, whichever comes first, any subsequent adjustments would be recorded in our consolidated statements of comprehensive income. *Segment Information* We operate in and report on one segment, which is supply chain management solutions. *Risk and Uncertainties* We rely on hardware and software licensed from third parties to offer our on-demand solutions. Our management believes alternate sources are available; however, disruption or termination of these relationships could adversely affect our operating results in the near term. *Concentration of Credit Risk* Financial instruments that potentially subject us to concentrations of credit risk consist principally of temporary cash and cash equivalents in financial institutions in excess of federally insured limits and trade accounts receivable. Temporary cash investments are held with financial institutions that we believe are subject to minimal risk. *Cash and Cash Equivalents* Cash and cash equivalents consist of cash and highly liquid investments with original maturities of less than 90 days. Cash and cash equivalents are stated at fair value. *Marketable Securities* Management determines the appropriate classification of marketable securities at the time of purchase and reevaluates such determination at each balance sheet date. Securities are classified as available for sale and are carried at fair value, with the change in unrealized gains and losses, net of tax, reported as a separate component on the consolidated statements of comprehensive income. Fair value is determined based on quoted market rates when observable or utilizing data points that are observable, such as quoted prices, interest rates and yield curves. When a determination has been made that an other-than-temporary decline in fair value has occurred, the amount of the decline that is related to a credit loss is realized and is included in other income (expense), net in the consolidated statements of comprehensive income. *Fair Value of Financial Instruments* The carrying amounts of our financial instruments, which include cash, cash equivalents, accounts receivable, accounts payable and other accrued expenses, approximates fair value due to their short maturities. Marketable securities are recorded at fair value as further described in Note C. *Accounts Receivable* Accounts receivable are initially recorded upon the sale of solutions to customers. Credit is granted in the normal course of business without collateral. Accounts receivable are stated net of allowances for doubtful accounts, which represent estimated losses resulting from the inability of certain customers to make the required payments. When determining the allowances for doubtful accounts, we take several factors into consideration including the overall composition of the accounts receivable aging, our prior history of accounts receivable write-offs, the type of customers and our experience with specific customers. We write off accounts receivable when they are determined to be uncollectible. Changes in the allowances for doubtful accounts are recorded as bad debt expense and are included in general and administrative expense in our consolidated statements of comprehensive income. *Property and Equipment* Property and equipment, including assets acquired under capital lease obligations, are stated at cost, net of accumulated depreciation and amortization. Depreciation and amortization are computed using the straight-line method over the estimated useful lives when placed in service, which are: Computer equipment and software: 2 to 3 years Office equipment and furniture: 5 to 7 years Leasehold improvements: the shorter of the useful life of the asset or the remaining term of the lease Significant additions or improvements extending asset lives beyond one year are capitalized, while repairs and maintenance are charged to expense as incurred. We also capitalize and amortize eligible costs to acquire or develop internal-use software that are incurred during the development stage. The assets and related accumulated depreciation and amortization are adjusted for asset retirements and disposals with the resulting gain or loss included in our consolidated statements of comprehensive income. *Research and Development* Research and development costs primarily include maintenance and data conversion activities related to our cloud-based supply chain management solutions and are expensed as incurred. *Goodwill* Goodwill represents the excess of the purchase price over the fair value of identifiable net assets acquired in business combinations. We test goodwill for impairment annually at November 30, or more frequently if events or changes in circumstances indicate that the asset might be impaired. The impairment test is conducted by comparing the fair value of the net assets with the carrying value of the reporting unit. Fair value is determined using the direct market observation of market price and outstanding equity of the reporting unit at the testing date. If the carrying value of the goodwill exceeds the fair value of the reporting unit, goodwill may be impaired. If this occurs, the fair value is then allocated to its assets and liabilities in a manner similar to a purchase price allocation in order to determine the implied fair value of goodwill. This implied fair value is then compared to the carrying amount of goodwill and, if it is less, we would recognize an impairment loss. During 2016, we changed our annual impairment testing date from December 31 to November 30. This voluntary change in accounting principle, applied prospectively, is preferable as it allows more timely completion of our annual impairment test and does not delay, accelerate, or avoid an impairment charge. *Intangible Assets* Assets acquired in business combinations may include identifiable intangible assets such as subscriber relationships and non-competition agreements. We recognize separately from goodwill the fair value of the identifiable intangible assets acquired. We have determined the fair value and useful lives of our purchased intangible assets using certain estimates and assumptions that we believe are reasonable. The purchased intangible assets are being amortized on a straight-line basis over their estimated useful lives, which are three to nine years for subscriber relationships, two to five years for non-competition agreements and one to four years for technology and other. *Impairment of Long-Lived Assets* We review our long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. The carrying amount of a long-lived asset is not recoverable if the carrying amount of an asset group exceeds the sum of the undiscounted cash flows expected to result from the use and eventual disposition of the assets at the date it is tested for recoverability, whether in use or under development. An impairment loss is measured as the amount by which the carrying amount of a long-lived asset exceeds its fair value. *Revenue Recognition* We generate revenues by providing a number of solutions to our customers. These solutions include Trading Partner Fulfillment, Trading Partner Enablement and Trading Partner Analytics. Our cloud-based solutions allow customers to meet their supply chain management requirements. Sales taxes are presented on a net basis within revenue. Revenues are recognized when all of the following criteria are met: (1) persuasive evidence of an arrangement exists, (2) delivery has occurred, (3) the fee is fixed or determinable, and (4) collectability is probable. If collection is not considered probable, revenues are recognized when the fees are collected. Fees related to our Trading Partner Fulfillment and Trading Partner Analytics solutions consist of two revenue sources: set-up fees and recurring monthly fees. Set-up fees are specific for each connection a customer has with a trading partner and most of our customers have connections with numerous trading partners. Set-up fees are nonrefundable upfront fees that do not have standalone value to our customer and are not separable from the recurring monthly fees. All set-up fees and related costs are deferred and recognized ratably over the average life of the connection between the customer and the trading partner, which is approximately two years. We begin recognizing set-up fee revenue once the connection is established. Set-up fees for which connections have not yet been established are classified as long-term. We continue to evaluate the length of the amortization period as more experience is gained with cancellations and technology changes requested by our customers. It is possible that, in the future, the period over which such subscription set-up fees and costs are amortized may be adjusted. Any change in our estimate of the average connection life will affect our future results of operations. The recurring monthly fees are comprised of both fixed and transaction-based fees that are recognized as earned. *Stock-Based Compensation* We recognize the cost of all share-based payments to employees, including grants of employee stock options, in the financial statements based on the grant date fair value of those awards. This cost is recognized over the period for which an employee is required to provide service in exchange for the award. Benefits associated with tax deductions in excess of recognized compensation expense are reported as a cash flow from financing activities. We estimate the fair value of options granted using the Black-Scholes option pricing model. The estimation of stock awards that will ultimately vest requires judgment, and to the extent actual results differ from our estimates, such amounts will be recorded as an adjustment in the period estimates are revised. In valuing share-based awards, judgment is required in determining the expected volatility of common stock and the expected term individuals will hold their share-based awards prior to exercising. The expected volatility of the options is based on the historical volatility of our common stock. The expected term of the options is based on the simplified method which does not consider historical employee exercise behavior. *Advertising Costs* Advertising costs are charged to expense as incurred. Advertising costs were approximately $61,000, $47,000, and $23,000 for the years ended December 31, 2016, 2015 and 2014, respectively. Advertising costs are included in sales and marketing expenses in our consolidated statements of comprehensive income. *Income Taxes* We account for income taxes using the liability method, which requires recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the consolidated financial statements. Under this method, deferred tax assets and liabilities are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Deferred tax assets are reduced by a valuation allowance when it is not “more likely than not” that the deferred tax asset will be utilized. We assess our ability to realize our deferred tax assets at the end of each reporting period. Realization of our deferred tax assets is contingent upon future taxable earnings. Accordingly, this assessment requires significant estimates and judgment. If the estimates of future taxable income vary from actual results, our assessment regarding the realization of these deferred tax assets could change. Future changes in the estimated amount of deferred taxes expected to be realized will be reflected in our consolidated financial statements in the period the estimate is changed, with a corresponding adjustment to our operating results. We recognize the financial statement benefit of a tax position only after determining that the relevant tax authority would “more likely than not” sustain the position following an audit. For tax positions meeting the “more likely than not” threshold, the amount recognized in the financial statements is the largest benefit that has a greater than 50% likelihood of being realized upon ultimate settlement with the relevant tax authority. *Net Income Per Share* Basic net income per share has been computed using the weighted average number of shares of common stock outstanding during each period. Diluted net income per share also includes the impact of our outstanding potential common shares, including options, restricted stock units and restricted stock awards. Potential common shares that are anti-dilutive are excluded from the calculation of diluted net income per share. *Recent Accounting Pronouncements* In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (Topic 606), which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. This guidance will replace most existing revenue recognition guidance in GAAP when it becomes effective. These new requirements are effective for annual reporting periods beginning after December 15, 2017, and interim periods within those annual periods. We do not believe the new revenue recognition standard will materially impact our recognition of the primary fees received from customers for our cloud-based supply chain solutions. We believe the adoption of the new standard could impact our accounting for certain upfront set-up fees and the periods over which the related revenues are recognized, as well as the timing of cost recognition for sales commissions and other contract acquisition costs. We are currently evaluating implementation methods and the extent of the impact that implementation of this standard will have on our consolidated financial statements upon adoption In November 2015, the FASB issued ASU No. 2015-17, Balance Sheet Classification of Deferred Taxes, which amends the guidance requiring companies to separate deferred income tax liabilities and assets into current and non-current amounts in a classified statement of financial position. This accounting guidance simplifies the presentation of deferred income taxes, such that deferred tax liabilities and assets be classified as non-current in a classified statement of financial position. This accounting guidance is effective for us beginning in the first quarter of 2017, but we elected to early adopt this guidance prospectively as of December 31, 2015. As a result, we have classified all deferred tax liabilities and assets as non-current in the condensed consolidated balance sheet as of December 31, 2016 and December 31, 2015. In February 2016, the FASB issued ASU 2016-02, Leases which will supersede the existing lease guidance and will require all leases with a term greater than 12 months to be recognized in the statements of financial position and eliminate current real estate-specific lease guidance, while maintaining substantially similar classification criteria for distinguishing between finance leases and operating leases. This standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018, with early adoption permitted. We believe the adoption of the new lease accounting standard will materially impact our consolidated financial statements by increasing our non-current assets and non-current liabilities on our consolidated balance sheets in order to record the right of use assets and related lease liabilities for our existing operating leases. We are in the process of determining the financial statement impact and are currently unable to estimate the impact on our consolidated financial statements. In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting, which permits entities to make an accounting policy election related to how forfeitures will impact the recognition of compensation cost for stock-based compensation, and also eliminates the requirement that excess tax benefits be realized as a reduction in current taxes payable before the associated tax benefit can be recognized as an increase in paid in capital. This standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2016, with early adoption permitted. We expect that our previously unrecognized federal and state net operating losses ($46.2 million and $10.7 million, respectively, as of December 31, 2016) will be included in the deferred tax assets recognized in our consolidated balance sheets on a modified retrospective basis as of January 1, 2017. With the adoption of ASU 2016-09 we will also be required to present excess tax benefits as an operating activity in the same manner as other cash flows related to income taxes on the statement of cash flows rather than as a financing activity.

Business Acquisitions

12 Months Ended

Dec. 31, 2016

Business Combinations [Abstract]

Business Acquisitions

NOTE B – Business Acquisitions

Toolbox Solutions, Inc.

On January 5, 2016, we completed our acquisition of all of the outstanding common shares of Toolbox Solutions, Inc. (“Toolbox Solutions”), a privately held company providing point-of-sale analytics and category management services to retailers and consumer packaged goods suppliers in North America. This acquisition expanded our retail network and strengthened our analytics offerings. Pursuant to the share purchase agreement, we paid $18.0 million in cash and issued $2.9 million in stock, or 43,953 shares of common stock, to the shareholders of Toolbox Solutions. The purchase agreement also allowed the sellers to receive up to 16,222 additional shares of common stock, which would have become payable contingent upon the completion of certain revenue milestones, none of which were met, and therefore, no additional shares were issued. During the year ended December 31, 2016, we recognized other income of $1.1 million in our consolidated statements of comprehensive income due to the remeasurement of this contingent liability.

Purchase Price Allocation

We accounted for the acquisition as a business combination. We allocated the purchase price to the tangible and identifiable intangible assets acquired and liabilities assumed based on their estimated fair values as of the acquisition date. We engaged a third-party valuation firm to assist us in the determination of the value of the purchased intangible assets. The excess of the purchase price over the fair value of net tangible and identifiable intangible assets acquired was recorded as goodwill. Goodwill is attributed to a trained workforce and other buyer-specific value resulting from expected synergies, including long-term cost savings, which are not included in the fair values of identifiable assets.

The purchase price consisted of the following (in thousands):


Cash	$	18,032
SPS Commerce, Inc. common stock		2,922
Fair value of share-based earn-out liability		1,043

	$	21,997

The final purchase price was subject to a net working capital adjustment to be determined by us and the sellers, pursuant to the terms of the purchase agreement. The number of shares of our common stock issued for the acquisition was a net of 43,953 shares, which consisted of 48,668 shares issued at closing, as calculated according to the terms of the purchase agreement, less 4,715 shares that were returned to us from escrow in the fourth quarter of 2016.

The following table summarizes the estimated fair values of the assets acquired, net of cash acquired of $359,000, and liabilities assumed at the acquisition date (in thousands):


Current assets	$	1,253
Property and equipment		56
Goodwill		15,389
Intangible assets		9,070
Current liabilities		(1,249	)
Deferred revenue		(301	)
Deferred income tax liability		(2,221	)

	$	21,997

Purchased Intangible Assets

The following table summarizes the estimated fair value of the purchased intangible assets and their estimated useful lives:


Purchased Intangible Assets	Estimated Fair Value (in thousands)		Estimated Life (in years)
Subscriber relationships	$	7,400		8
Developed technology		1,200		4
Trade names		70		1
Non-competition agreements		400		5

Total	$	9,070

The purchased intangible assets are being amortized on a straight-line basis over their estimated useful lives. Amortization expense for the period from January 5, 2016 through December 31, 2016 was $1.4 million.

Acquisition-Related Costs and Post-Acquisition Operating Results

Acquisition-related costs were $147,000 and are included in our consolidated statement of comprehensive income for the year ended December 31, 2016. The operating results of Toolbox Solutions have been included in our consolidated financial statements from January 5, 2016, the closing date of the acquisition. For the period from January 5, 2016 through December 31, 2016, approximately $7.9 million of our revenues were derived from Toolbox Solutions’ products and services. The amount of operating income or loss from Toolbox Solutions was not separately identifiable due to our integration.

Unaudited Pro Forma Financial Information

The unaudited pro forma financial information in the table below presents the combined operating results of SPS Commerce and Toolbox Solutions as if the acquisition had occurred on January 1, 2015. The unaudited pro forma information includes the historical operating results of each company and pro forma adjustments for the approximately $1.4 million of annual amortization expense related to purchased intangible assets and the additional impact on the provision or benefit for income taxes, resulting from the combined income and intangible amortization expense, using our statutory blended income tax rate of 26.5%.


	Year Ended December 31,
(in thousands, except per share data)	2016		2015
Pro forma total revenue	$	193,525	$	166,873
Pro forma net income		5,976		2,400
Pro forma net income per share
Basic		0.35		0.14
Diluted		0.35		0.14

The unaudited pro forma financial information is presented for informational purposes only and is not necessarily indicative of the results of operations that would have actually been reported had the acquisition occurred on January 1, 2015, nor is it necessarily indicative of our results of operations for any future periods.

Leadtec

On October 12, 2014, we entered into and completed an asset purchase agreement with Leadtec Systems Australia Pty Ltd (“Leadtec”), and its affiliates, Advanced Barcode Solutions Pty Ltd, Scott Needham and Leading Technology Group Pty Ltd. Leadtec is in the business of cloud-based integration solutions. Pursuant to the asset purchase agreement, we purchased and acquired from Leadtec substantially all of the assets used in Leadtec’s business and assumed certain liabilities of Leadtec, all of which were recorded in Australian dollars. We paid $12.6 million in cash and issued 43,595 shares of our common stock for this acquisition, which expanded our base of recurring revenue customers and added suppliers to our network.

Purchase Price Allocation

We accounted for the acquisition as a business combination. We allocated the purchase price to the tangible and identifiable intangible assets acquired and liabilities assumed based on their estimated fair values as of the acquisition date. The excess of the purchase price over the fair value of net tangible and identifiable intangible assets acquired was recorded as goodwill. Goodwill is attributed to buyer-specific value resulting from expected synergies, including long-term cost savings, as well as a trained workforce which are not included in the fair values of assets. Goodwill will not be amortized; however the value is deductible for tax purposes.

The purchase price consisted of the following (in thousands):


Cash	$	12,595
SPS Commerce, Inc. common stock		2,203

	$	14,798

The number of shares of our common stock issued for the acquisition was 43,595 shares as calculated according to the terms of the purchase agreement. The fair value of the shares issued was approximately $2.2 million and was determined using the closing price of our common stock on October 10, 2014.

The following table summarizes the estimated fair values of the assets acquired and liabilities assumed at the acquisition date (in thousands):


Current and other assets	$	659
Property and equipment		143
Goodwill		9,954
Intangible assets		4,891
Current liabilities		(849	)

	$	14,798

Purchased Intangible Assets

The following table summarizes the estimated fair value of the purchased intangible assets and their estimated useful lives:


Purchased Intangible Assets	Estimated Fair Value (in thousands)		Estimated Life (in years)
Subscriber relationships	$	3,778		9
Non-competition agreements		148		5
Technology and other		965		2.5

Total	$	4,891

The purchased intangible assets are being amortized on a straight-line basis over their estimated useful lives. Amortization expense related to these intangible assets was $733,000 for the year ended December 31, 2015 and $168,000 for the period from October 12, 2014 through December 31, 2014.

Acquisition-Related Costs and Post-Acquisition Operating Results

Acquisition-related costs were $690,000, including $338,000 for a one-time Australian stamp duty tax, and are included in our consolidated statement of comprehensive income for the year ended December 31, 2014. The operating results of Leadtec have been included in our consolidated financial statements from October 12, 2014, the closing date of the acquisition. For the period from October 12, 2014 through December 31, 2014, revenues of approximately $1.2 million and an operating loss of approximately $280,000 were attributable to Leadtec.

Unaudited Pro Forma Financial Information

The unaudited pro forma financial information in the table below presents the combined operating results of SPS Commerce and Leadtec as if the acquisition had occurred on January 1, 2013. The unaudited pro forma information includes the historical operating results of each company and pro forma adjustments for annual amortization expense related to purchased intangible assets and the expected tax impact considering our current tax elections and representations.


	Year Ended December 31,
(in thousands, except per share data)	2014
Pro forma total revenue	$	132,818
Pro forma net income		2,973
Pro forma net income per share
Basic		0.18
Diluted		0.18

The unaudited pro forma financial information is presented for informational purposes only and is not necessarily indicative of the results of operations that would have actually been reported had the acquisition occurred on January 1, 2013, nor is it necessarily indicative of our results of operations for any future periods.

- Definition

The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 15: http://www.xbrl.org/2003/role/presentationRef
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+ Details

Financial Instruments

12 Months Ended

Dec. 31, 2016

Investments, Debt and Equity Securities [Abstract]

Financial Instruments

NOTE C – Financial Instruments

We invest primarily in money market funds, highly liquid debt instruments of the U.S. government, and U.S. corporate debt securities. All highly liquid investments with original maturities of 90 days or less are classified as cash equivalents. All investments with original maturities greater than 90 days and remaining maturities less than one year from the balance sheet date are classified as short-term marketable securities. Investments with remaining maturities of more than one year from the balance sheet date are classified as marketable securities, non-current. Short-term marketable securities and marketable securities, non-current, are also classified as available-for-sale. We intend to hold marketable securities until maturity; however, we may sell these securities at any time for use in current operations or for other purposes. Consequently, we may or may not keep securities with stated holding periods to maturity.

Our fixed income investments are carried at fair value and unrealized gains and losses on these investments, net of taxes, are included in accumulated other comprehensive loss in the consolidated balance sheets. Realized gains or losses are included in other income (expense) in the consolidated statements of comprehensive income. When a determination has been made that an other-than-temporary decline in fair value has occurred, the amount of the decline that is related to a credit loss is realized and is included in other income (expense), net in the consolidated statements of comprehensive income.

Cash equivalents and marketable securities, consisted of the following (in thousands):


	December 31,
	2016							2015
	Amortized Cost		Unrealized Gains (Losses)			Fair Value		Amortized Cost		Unrealized Gains (Losses)			Fair Value
Cash equivalents:
Money market funds	$	75,375	$	—		$	75,375	$	79,717	$	—		$	79,717
Marketable securities:
Corporate bonds		15,681		(96	)		15,585		10,042		(34	)		10,008
Commercial paper		4,977		10			4,987		2,499		1			2,500
U.S. treasury securities		7,489		10			7,499		7,489		(27	)		7,462
U.S. agency obligations		2,497		3			2,500		2,497		1			2,498

	$	106,019	$	(73	)	$	105,946	$	102,244	$	(59	)	$	102,185

Due within one year						$	98,452						$	87,235
Due within two years							7,494							14,950

Total						$	105,946						$	102,185

We do not believe any of the unrealized losses represent an other-than-temporary impairment based on our assessment of available evidence as of December 31, 2016. We expect to receive the full principal and interest on all of these cash equivalents and marketable securities.

Fair Value Measurements

We measure certain financial assets at fair value on a recurring basis based on a fair value hierarchy that requires us to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. A financial instrument’s categorization within the fair value hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The three levels of inputs that may be used to measure fair value are:

•

Level 1 — quoted prices in active markets for identical assets or liabilities

•

Level 2 — observable inputs other than Level 1 prices, such as (a) quoted prices for similar assets or liabilities, (b) quoted prices in markets with insufficient volume or infrequent transactions (less active markets), or (c) model-derived valuations in which all significant inputs are observable or can be derived principally from or corroborated by observable market data for substantially the full term of the assets or liabilities.

•

Level 3 — unobservable inputs to the valuation methodology that are significant to the measurement of fair value of assets or liabilities.

Level 1 Measurements

Our cash equivalents held in money market funds are measured at fair value using level 1 inputs.

Level 2 Measurements

Our available-for-sale U.S. treasury securities, U.S. agency obligations, commercial paper and corporate debt securities are measured at fair value using level 2 inputs. We obtain the fair values of our level 2 available-for-sale securities from a professional pricing service.

The following table presents information about our financial assets that are measured at fair value on a recurring basis and indicates the fair value hierarchy of the valuation techniques utilized to determine such fair value (in thousands):


	Level 1		Level 2		Level 3		Total
Assets at December 31, 2016:
Cash and cash equivalents:
Money market funds	$	75,375	$	—	$	—	$	75,375
Marketable securities:
Corporate bonds		—		15,585		—		15,585
Commerical paper		—		4,987		—		4,987
U.S. treasury securities		—		7,499		—		7,499
U.S. agency obligations		—		2,500		—		2,500

	$	75,375	$	30,571	$	—	$	105,946

Assets at December 31, 2015:
Cash and cash equivalents:
Money market funds	$	79,717	$	—	$	—	$	79,717
Marketable securities:
Corporate bonds		—		10,008		—		10,008
Commerical paper		—		2,500		—		2,500
U.S. treasury securities		—		7,462		—		7,462
U.S. agency obligations		—		2,498		—		2,498

	$	79,717	$	22,468	$	—	$	102,185

- Definition

The entire disclosure for investments in certain debt and equity securities.

+ References + Details

Allowance for Doubtful Accounts

12 Months Ended

Dec. 31, 2016

Text Block [Abstract]

Allowance for Doubtful Accounts

NOTE D – Allowance for Doubtful Accounts

The allowance for doubtful accounts activity, included in accounts receivable, net, was as follows (in thousands):


	2016			2015			2014
Balances, January 1	$	446		$	279		$	237
Provision for doubtful accounts		1,375			1,271			717
Write-offs, net of recoveries		(1,306	)		(1,104	)		(675	)

Balances, December 31	$	515		$	446		$	279

Property and Equipment, net

12 Months Ended

Dec. 31, 2016

Property, Plant and Equipment [Abstract]

Property and Equipment, net

NOTE E – Property and Equipment, net

Property and equipment, net included the following (in thousands):


	December 31,
	2016			2015
Computer equipment and software	$	29,270		$	27,725
Office equipment and furniture		7,087			5,793
Leasehold improvements		7,844			5,530

		44,201			39,048
Less: accumulated depreciation and amortization		(28,887	)		(25,428	)

	$	15,314		$	13,620

At December 31, 2016 and 2015, property and equipment, net included approximately $2.1 million and $709,000, respectively, of assets held at subsidiary and office locations outside of the United States of America.

Goodwill and Intangible Assets, net

12 Months Ended

Dec. 31, 2016

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets, net

NOTE F – Goodwill and Intangible Assets, net

The changes in the net carrying amount of goodwill for the years ended December 31, 2016 and 2015 are as follows (in thousands):


	2016		2015
Balances, January 1	$	33,848	$	34,854
Additions from business acquisitions		15,389		—
Foreign currency translation		540		(1,006	)

Balances, December 31	$	49,777	$	33,848

Intangible assets, net included the following (in thousands):


	December 31, 2016
	Carrying Amount		Accumulated Amortization			Foreign Currency Translation		Net
Subscriber relationships	$	33,736	$	(15,708	)	$	295	$	18,323
Non-competition agreements		2,234		(1,818	)		17		433
Technology and other		2,089		(1,120	)		63		1,032

	$	38,059	$	(18,646	)	$	375	$	19,788


	December 31, 2015
	Carrying Amount		Accumulated Amortization			Foreign Currency Translation			Net
Subscriber relationships	$	26,701	$	(11,856	)	$	(364	)	$	14,481
Non-competition agreements		1,843		(1,653	)		(9	)		181
Technology and other		905		(400	)		(86	)		419

	$	29,449	$	(13,909	)	$	(459	)	$	15,081

Amortization expense was $4.7 million, $3.3 million, and $2.9 million for the years ended December 31, 2016, 2015, and 2014, respectively. At December 31, 2016, future amortization expense for intangible assets was as follows (in thousands):


2017	$	4,380
2018		3,793
2019		3,502
2020		3,174
2021		2,381
Thereafter		2,558

	$	19,788

- Definition

The entire disclosure for the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain (loss) on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final. May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss.

+ References + Details

Commitments and Contingencies

12 Months Ended

Dec. 31, 2016

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

NOTE G – Commitments and Contingencies

Operating Leases

We are obligated under non-cancellable operating leases primarily for office space. Rent expense for all operating leases which includes minimum lease payments and other charges, such as common area maintenance fees, charged to operations was $5.0 million, $4.6 million and $3.7 million for the years ended December 31, 2016, 2015 and 2014, respectively.

On June 30, 2016, we executed a new lease agreement at our Toronto office location which commenced on January 1, 2017 and expires on December 31, 2021. The lease includes a right of first offer to lease certain additional space and one option to extend the term of the lease for five years at a market rate determined in accordance with the lease. There was also a rent holiday of two months which has been incorporated into our deferred rent calculation.

On September 1, 2015, we executed a new lease agreement at our New Jersey office location which commenced on February 1, 2016 and expires on June 30, 2023. The lease includes a right of first offer to lease certain additional space and one option to extend the term of the lease for five years at a market rate determined in accordance with the lease. There was also a rent holiday of five months which has been incorporated into our deferred rent calculation.

On February 14, 2012, we executed a new lease agreement for our current headquarters location which commenced on November 1, 2012 and expires on April 30, 2020. The lease includes additional square footage upon commencement, a right of first offer to lease certain additional space, which we exercised, and two options to extend the term of the lease for three years at a market rate determined in accordance with the lease. There was also a rent holiday from November 2012 to October 2013 which has been incorporated into our deferred rent calculation.

At December 31, 2016, our future minimum payments under operating leases were as follows (in thousands):


2017	$	3,318
2018		3,123
2019		3,220
2020		1,825
2021		1,047
Thereafter		1,174

	$	13,707

Other Contingencies

We may be involved in various claims and legal actions in the normal course of business. Our management believes that the outcome of any such claims and legal actions will not have a material effect on our financial position, results of operations or cash flows.

Stockholders' Equity	12 Months Ended
Stockholders' Equity	Dec. 31, 2016
Equity [Abstract]
Stockholders' Equity	NOTE H – Stockholders’ Equity *Common Stock Issued* In connection with the acquisition of Toolbox Solutions (see Note B), we issued a net of 43,953 shares which consisted of 48,668 shares issued at closing, as calculated according to the terms of the purchase agreement, less 4,715 shares that were returned to us from escrow in the fourth quarter of 2016. The fair value of the shares we issued, approximately $2.9 million, was determined using the closing price of our common stock on January 5, 2016. On October 12, 2014, in connection with the acquisition of Leadtec (see Note B), we issued 43,595 shares of our common stock. The fair value of the shares we issued, approximately $2.2 million, was determined using the closing price of our common stock on October 10, 2014.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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+ Details

Stock-Based Compensation

12 Months Ended

Dec. 31, 2016

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation

NOTE I – Stock-Based Compensation

Our equity compensation plans provide for the grant of incentive and nonqualified stock options, as well as other stock-based awards including restricted stock and restricted stock units, to employees, non-employee directors and other consultants who provide services to us. Restricted stock awards result in the issuance of new shares when granted. For other stock-based awards, new shares are issued when the award is exercised, vested or released according to the terms of the agreement. In February 2016, 1,003,439 additional shares were reserved for future issuance under our 2010 Equity Incentive Plan. At December 31, 2016, there were approximately 3.9 million shares available for grant under approved equity compensation plans.

We recorded stock-based compensation expense of $8.0 million, $6.4 million and $5.4 million for the years ended December 31, 2016, 2015 and 2014, respectively. This expense was allocated as follows (in thousands):


	Year Ended December 31,
	2016		2015		2014
Cost of revenues	$	1,309	$	989	$	614
Operating expenses
Sales and marketing		2,412		1,978		1,933
Research and development		618		640		444
General and administrative		3,684		2,772		2,405

Total stock-based compensation expense	$	8,023	$	6,379	$	5,396

As of December 31, 2016, there was approximately $13.7 million of unrecognized stock-based compensation expense under our equity compensation plans, which is expected to be recognized on a straight line basis over a weighted average period of 2.56 years.

Stock Options

Stock options generally vest over four years and have a contractual term of seven to ten years from the date of grant. Our stock option activity was as follows:


	Options (#)			Weighted Average Exercise Price ($/share)
Outstanding at January 1, 2014		1,097,223		$	19.62
Granted		153,770			62.86
Exercised		(153,196	)		12.27
Forfeited		(12,334	)		41.38

Outstanding at December 31, 2014		1,085,463			26.53
Granted		181,487			67.50
Exercised		(305,106	)		14.55
Forfeited		(18,741	)		45.82

Outstanding at December 31, 2015		943,103			37.91
Granted		340,609			48.58
Exercised		(221,630	)		19.42
Forfeited		(46,070	)		55.58

Outstanding at December 31, 2016		1,016,012			44.72

Of the total outstanding options at December 31, 2016, 582,650 were exercisable with a weighted average exercise price of $38.43 per share. The total outstanding options had a weighted average remaining contractual life of 4.6 years.

The fair value of options that vested during the years ended December 31, 2016, 2015 and 2014 was $3.4 million, $3.1 million and $2.9 million, respectively.

The intrinsic value of options exercised during the years ended December 31, 2016, 2015 and 2014 was $8.6 million, $16.8 million and $7.4 million, respectively. The intrinsic value of outstanding options at December 31, 2016, 2015 and 2014 was $25.6 million, $30.5 million and $33.8 million, respectively.

The weighted-average fair values per share of options granted during 2016, 2015 and 2014 were $16.13, $23.09 and $24.36, respectively. The fair values of the options granted were estimated on the date of grant using the Black-Scholes option pricing model with the following weighted-average assumptions:


	Year Ended December 31,
	2016			2015			2014
Volatility		38	%		39	%		42	%
Dividend yield		—			—			—
Life (in years)		4.54			4.52			4.17
Risk-free interest rate		1.19	%		1.36	%		1.44	%

The expected volatility of the options is based on the historical volatility of our common stock. We have not issued dividends on our common stock and do not expect to do so in the foreseeable future. The expected term of the options is based on the simplified method which does not consider historical employee exercise behavior. The risk-free interest rate is based on the U.S. Treasury rates at the date of grant with maturity dates approximately equal to the expected life at the grant date.

Restricted Stock Units and Awards

Restricted stock units vest over four years and, upon vesting, the holder is entitled to receive shares of our common stock. With restricted stock awards, shares of our common stock are issued when the award is granted and the restrictions lapse over one year.

Our restricted stock units activity was as follows:


	Restricted Stock Units (#)			Weighted Average Grant Date Fair Value ($/share)
Outstanding at January 1, 2014		102,644		$	33.77
Granted		42,001			64.89
Vested and common stock issued		(28,367	)		32.92
Forfeited		(1,145	)		35.42

Outstanding at December 31, 2014		115,133			45.25
Granted		68,159			67.50
Vested and common stock issued		(37,669	)		40.91
Forfeited		(5,058	)		54.28

Outstanding at December 31, 2015		140,565			56.88
Granted		115,896			48.32
Vested and common stock issued		(52,133	)		48.19
Forfeited		(15,286	)		55.48

Outstanding at December 31, 2016		189,042			54.14

The number of restricted stock units outstanding at December 31, 2016 included 34,190 units that have vested, but the shares of common stock have not yet been issued pursuant to the terms of the agreement.

Our restricted stock awards activity was as follows:


	Restricted Stock Awards (#)			Weighted Average Grant Date Fair Value ($/share)
Outstanding at January 1, 2014		1,422		$	48.66
Restricted common stock issued		5,352			51.74
Restrictions lapsed		(5,199	)		51.04
Forfeited		(237	)		48.66

Outstanding at December 31, 2014		1,338			51.74
Restricted common stock issued		4,110			67.37
Restrictions lapsed		(4,416	)		62.63
Forfeited		—			—

Outstanding at December 31, 2015		1,032			67.39
Restricted common stock issued		6,078			52.27
Restrictions lapsed		(5,586	)		55.06
Forfeited		—			—

Outstanding at December 31, 2016		1,524			52.28

Employee Stock Purchase Plan

Effective July 1, 2012, we adopted an employee stock purchase plan which allows participating employees to purchase shares of our common stock at a discount through payroll deductions. The plan is available to all employees subject to certain eligibility requirements. Participating employees may purchase common stock, on a voluntary after tax basis, at a price that is the lower of 85% of the fair market value of one share of common stock at the beginning or end of each stock purchase period. The plan consists of two six-month offering periods, beginning on January 1 and July 1 of each calendar year. A total of 1.1 million shares of common stock are reserved for issuance under the plan.

For the offering periods in 2016, we withheld approximately $1.7 million from employees participating in the plan and we purchased 33,357 shares on their behalf. For the offering periods in 2015, we withheld approximately $1.5 million from employees participating in the plan and we purchased 28,362 shares on their behalf. For the offering periods in 2014, we withheld approximately $1.3 million from employees participating in the plan and we purchased 26,353 shares on their behalf.

For the years ended December 31, 2016, 2015 and 2014, we recorded approximately $552,000, $408,000 and $473,000 of stock-based compensation expense associated with the employee stock purchase plan. The fair value was estimated based on the market price of our common stock at the beginning of each offering period and using the Black-Scholes option pricing model with the following weighted-average assumptions:


	Year Ended December 31,
	2016			2015			2014
Volatility		37	%		30	%		45	%
Dividend yield		—			—			—
Life (in years)		0.50			0.50			0.50
Risk-free interest rate		0.42	%		0.12	%		0.08	%

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References + Details

Income Taxes

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Income Taxes

NOTE J – Income Taxes

The provision for income taxes was as follows (in thousands):


	Year Ended December 31,
	2016			2015			2014
Current
Federal	$	3,684		$	2,066		$	43
State		555			289			254
Foreign		599			119			80
Deferred
Federal		(988	)		103			1,183
State		(133	)		(141	)		(152	)
Foreign		(577	)		—			—

	$	3,140		$	2,436		$	1,408

A reconciliation of the expected federal income tax at the statutory rate to the provision for income taxes was as follows (in thousands):


	Year Ended December 31,
	2016			2015			2014
Expected federal income tax at statutory rate	$	3,011		$	2,404		$	1,398
State income taxes, net of federal tax effect		320			246			124
Tax impact of foreign activity		(115	)		39			37
Permanent book/tax differences		372			67			173
Change in valuation allowance		(35	)		(27	)		(88	)
Change in state deferred rate		(67	)		(118	)		(9	)
Research and development credit		(261	)		(200	)		(178	)
Other		(85	)		25			(49	)

Total provision for income taxes	$	3,140		$	2,436		$	1,408

The significant components of our deferred tax assets (liabilities) were as follows (in thousands):


	December 31,
	2016						2015
Deferred tax assets
Net operating loss and credit carryforwards	$	4,614					$	4,687
Deferred operations		799						1,443
Stock-based compensation expense		4,085						3,284
Depreciation and amortization		—						1,179
Accounts receivable allowances		363						252
Accrued expenses		2,704						1,137
Other		297						234

Gross deferred tax asset					12,862						12,216
Less: valuation allowance		(649	)					(928	)

Total net deferred tax asset					12,213						11,288
Deferred tax liability
Foreign operations		(350	)					(139	)
Depreciation and amortization		(1,328	)					—

Total deferred tax liability					(1,678	)					(139	)

Net deferred tax assets				$	10,535					$	11,149

As of December 31, 2016, we had net operating loss carryforwards of $70.7 million for U.S. federal tax purposes. We also had $19.2 million of various state net operating loss carryforwards. The loss carryforwards for federal tax purposes will expire between 2019 and 2036 if not utilized. The loss carryforwards for state tax purposes will expire between 2017 and 2036 if not utilized.

Section 382 of the U.S. Internal Revenue Code generally imposes an annual limitation on the amount of net operating loss carryforwards that might be used to offset taxable income when a corporation has undergone significant changes in stock ownership. We have performed a Section 382 analysis for the time period from our inception through December 8, 2010. During this time period it was determined that we had six separate ownership changes under Section 382. We have not updated the Section 382 analysis subsequent to December 8, 2010; however, we believe there have not been any events subsequent to that date that would materially impact the analysis. We believe that approximately $17.6 million of federal losses will expire unused due to Section 382 limitations. The maximum annual limitation of federal net operating losses under Section 382 is approximately $990,000. This limitation could be further restricted if any ownership changes occur in future years.

Our federal and state net operating losses at December 31, 2016 included $46.2 million and $10.7 million, respectively, of income tax deductions in excess of previously recorded tax benefits. Although these additional tax deductions are included in the net operating losses referenced above, the related tax benefit will not be recognized until the deductions reduce our income taxes payable. The tax benefit of these excess deductions will be reflected as a credit to additional paid in capital when recognized. Accordingly, our deferred tax assets are reported net of the excess tax deductions for stock compensation and Section 382 limitations.

As of December 31, 2016 we had federal research and development credit carryforwards, net of Section 383 limitations, of $980,000, which, if not utilized, will begin to expire in 2030. We had state research and development credit carryforwards of $461,000, which, if not utilized, will begin to expire in 2025.

As of December 31, 2016, we had a valuation allowance against our deferred tax assets of $649,000. The valuation allowance is established for state net operating loss and credit carryforwards that we do not expect to utilize based on our current expectations of future state taxable income.

We are subject to income taxes in the U.S. federal and various state and international jurisdictions. We are generally subject to U.S. federal and state tax examinations for all prior tax years due to our net operating loss carryforwards and the utilization of the carryforwards in years still open under statute.

As of December 31, 2016, we do not have any unrecognized tax benefits. It is our practice to recognize interest and penalties accrued on any unrecognized tax benefits as a component of income tax expense. We do not expect any material changes in our unrecognized tax positions over the next 12 months.

Net Income Per Share

12 Months Ended

Dec. 31, 2016

Earnings Per Share [Abstract]

Net Income Per Share

NOTE K – Net Income Per Share

The following table presents the components of the computation of basic and diluted net income per share for the periods indicated (in thousands, except per share amounts):


	Year Ended December 31,
	2016		2015		2014
Numerator
Net income	$	5,710	$	4,639	$	2,704
Denominator
Weighted average common shares outstanding, basic		16,947		16,565		16,236
Options to purchase common stock		267		437		535
Restricted stock units		27		27		42
Employee stock purchase plan		—		3		1

Weighted average common shares outstanding, diluted		17,241		17,032		16,814

Net income per share
Basic	$	0.34	$	0.28	$	0.17
Diluted	$	0.33	$	0.27	$	0.16

For the years ended December 31, 2016, 2015, and 2014, the effect of approximately 5,000, 4,000 and 126,000 outstanding potential common shares, respectively, were excluded from the calculation of diluted net income per share because they were anti-dilutive.

Retirement Savings Plan	12 Months Ended
Retirement Savings Plan	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Retirement Savings Plan	NOTE L – Retirement Savings Plan We sponsor a 401(k) retirement savings plan for our U.S. employees. Employees can contribute up to 100% of their compensation, subject to the limits established by law. We match 25% of the employee’s contribution up to the first 6% of pre-tax annual compensation. Additionally, we make statutory contributions to retirement plans as required by local foreign government regulations. Our contributions to the plans, which vest immediately, were $1.4 million, $1.1 million and $733,000 for the years ended December 31, 2016, 2015 and 2014, respectively.

Related Party Transactions	12 Months Ended
Related Party Transactions	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party Transactions	NOTE M – Related Party Transactions SPS Commerce Foundation (the “Foundation”) is a Minnesota non-profit organization exempt from federal taxation under Section 501(c)(3) of the Internal Revenue Code. The Foundation was formed in 2015 to engage in, advance, support, promote and administer charitable activities. The directors of the Foundation are also our officers. These officers receive no compensation from the Foundation for the management services performed for the Foundation. The Foundation is not a subsidiary of ours and the financial results of the Foundation are not consolidated with our financial statements. We made contributions of $250,000 and $500,000 to the Foundation for the years ended 2016 and 2015, respectively. We have no current legal obligations for future commitments to the Foundation.

Selected Quarterly Financial Data (Unaudited)

12 Months Ended

Dec. 31, 2016

Quarterly Financial Information Disclosure [Abstract]

Selected Quarterly Financial Data (Unaudited)

NOTE N – Selected Quarterly Financial Data (Unaudited)

The following table presents our selected unaudited quarterly statements of comprehensive income data (in thousands, except per share amounts):


	For the Three Months Ended
2016	Mar 31		Jun 30		Sep 30		Dec 31
Revenues	$	45,599	$	47,351	$	49,284	$	51,061
Gross profit		30,718		31,379		33,113		33,739
Income from operations		1,314		880		2,670		2,653
Net income		1,044		352		2,509	$	1,805
Diluted earnings per share	$	0.06	$	0.02	$	0.14	$	0.10


	For the Three Months Ended
2015	Mar 31		Jun 30		Sep 30		Dec 31
Revenues	$	36,970	$	38,846	$	40,354	$	42,348
Gross profit		25,398		26,511		27,654		28,912
Income from operations		922		1,027		2,260		2,814
Net income		586		651		1,270		2,132
Diluted earnings per share	$	0.03	$	0.04	$	0.07	$	0.12

General (Policies)	12 Months Ended
General (Policies)	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business Description	*Business Description* We are a leading provider of cloud-based supply chain management solutions, providing network-proven fulfillment, sourcing and item assortment management solutions, along with comprehensive retail performance analytics, to thousands of customers worldwide. We provide our solutions through the SPS Commerce platform, a cloud-based product suite that improves the way suppliers, retailers, distributors and logistics firms orchestrate the sourcing, set up of new vendors and items, and fulfillment of the products that customers buy from retailers and suppliers. We derive the majority of our revenues from thousands of monthly recurring subscriptions from businesses that utilize our solutions.
Basis of Presentation	*Basis of Presentation* The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and include the accounts of SPS Commerce, Inc. and its subsidiaries. All intercompany accounts and transactions have been eliminated in the consolidated financial statements.
Foreign Currency Translation	*Foreign Currency Translation* Assets and liabilities denominated in currencies other than the U.S. dollar are translated into U.S. dollars at the exchange rates in effect at the balance sheet date, with the resulting translation adjustments recorded as a separate component of accumulated other comprehensive loss. Income and expense accounts are translated at the average exchange rates during the year. Foreign currency transaction gains and losses, if any, are included in net income.
Use of Estimates	*Use of Estimates* Preparing financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates.
Business Combinations	*Business Combinations* We recognize separately from goodwill the fair value of the assets acquired and the liabilities assumed at the acquisition date. Goodwill as of the acquisition date is measured as the excess of consideration transferred and the net of the acquisition date amounts of the assets acquired and the liabilities assumed. Assets acquired include tangible and intangible assets. We use estimates and assumptions that we believe are reasonable as a part of determining the value and useful lives of purchased intangible assets and the purchase price allocation process. While we believe these estimates and assumptions are reasonable, they are inherently uncertain and subject to refinement. As a result, during the measurement period, which may be up to one year from the acquisition date, we may record adjustments to the fair value of the assets acquired and the liabilities assumed. Any such adjustments would be recorded as an offset to goodwill. Upon the conclusion of the measurement period or final determination of the fair values, whichever comes first, any subsequent adjustments would be recorded in our consolidated statements of comprehensive income.
Segment Information	*Segment Information* We operate in and report on one segment, which is supply chain management solutions.
Risk and Uncertainties	*Risk and Uncertainties* We rely on hardware and software licensed from third parties to offer our on-demand solutions. Our management believes alternate sources are available; however, disruption or termination of these relationships could adversely affect our operating results in the near term.
Concentration of Credit Risk	*Concentration of Credit Risk* Financial instruments that potentially subject us to concentrations of credit risk consist principally of temporary cash and cash equivalents in financial institutions in excess of federally insured limits and trade accounts receivable. Temporary cash investments are held with financial institutions that we believe are subject to minimal risk.
Cash and Cash Equivalents	*Cash and Cash Equivalents* Cash and cash equivalents consist of cash and highly liquid investments with original maturities of less than 90 days. Cash and cash equivalents are stated at fair value.
Marketable Securities	*Marketable Securities* Management determines the appropriate classification of marketable securities at the time of purchase and reevaluates such determination at each balance sheet date. Securities are classified as available for sale and are carried at fair value, with the change in unrealized gains and losses, net of tax, reported as a separate component on the consolidated statements of comprehensive income. Fair value is determined based on quoted market rates when observable or utilizing data points that are observable, such as quoted prices, interest rates and yield curves. When a determination has been made that an other-than-temporary decline in fair value has occurred, the amount of the decline that is related to a credit loss is realized and is included in other income (expense), net in the consolidated statements of comprehensive income.
Fair Value of Financial Instruments	*Fair Value of Financial Instruments* The carrying amounts of our financial instruments, which include cash, cash equivalents, accounts receivable, accounts payable and other accrued expenses, approximates fair value due to their short maturities. Marketable securities are recorded at fair value as further described in Note C.
Accounts Receivable	*Accounts Receivable* Accounts receivable are initially recorded upon the sale of solutions to customers. Credit is granted in the normal course of business without collateral. Accounts receivable are stated net of allowances for doubtful accounts, which represent estimated losses resulting from the inability of certain customers to make the required payments. When determining the allowances for doubtful accounts, we take several factors into consideration including the overall composition of the accounts receivable aging, our prior history of accounts receivable write-offs, the type of customers and our experience with specific customers. We write off accounts receivable when they are determined to be uncollectible. Changes in the allowances for doubtful accounts are recorded as bad debt expense and are included in general and administrative expense in our consolidated statements of comprehensive income.
Property and Equipment	*Property and Equipment* Property and equipment, including assets acquired under capital lease obligations, are stated at cost, net of accumulated depreciation and amortization. Depreciation and amortization are computed using the straight-line method over the estimated useful lives when placed in service, which are: Computer equipment and software: 2 to 3 years Office equipment and furniture: 5 to 7 years Leasehold improvements: the shorter of the useful life of the asset or the remaining term of the lease Significant additions or improvements extending asset lives beyond one year are capitalized, while repairs and maintenance are charged to expense as incurred. We also capitalize and amortize eligible costs to acquire or develop internal-use software that are incurred during the development stage. The assets and related accumulated depreciation and amortization are adjusted for asset retirements and disposals with the resulting gain or loss included in our consolidated statements of comprehensive income.
Research and Development	*Research and Development* Research and development costs primarily include maintenance and data conversion activities related to our cloud-based supply chain management solutions and are expensed as incurred.
Goodwill	*Goodwill* Goodwill represents the excess of the purchase price over the fair value of identifiable net assets acquired in business combinations. We test goodwill for impairment annually at November 30, or more frequently if events or changes in circumstances indicate that the asset might be impaired. The impairment test is conducted by comparing the fair value of the net assets with the carrying value of the reporting unit. Fair value is determined using the direct market observation of market price and outstanding equity of the reporting unit at the testing date. If the carrying value of the goodwill exceeds the fair value of the reporting unit, goodwill may be impaired. If this occurs, the fair value is then allocated to its assets and liabilities in a manner similar to a purchase price allocation in order to determine the implied fair value of goodwill. This implied fair value is then compared to the carrying amount of goodwill and, if it is less, we would recognize an impairment loss. During 2016, we changed our annual impairment testing date from December 31 to November 30. This voluntary change in accounting principle, applied prospectively, is preferable as it allows more timely completion of our annual impairment test and does not delay, accelerate, or avoid an impairment charge.
Intangible Assets	*Intangible Assets* Assets acquired in business combinations may include identifiable intangible assets such as subscriber relationships and non-competition agreements. We recognize separately from goodwill the fair value of the identifiable intangible assets acquired. We have determined the fair value and useful lives of our purchased intangible assets using certain estimates and assumptions that we believe are reasonable. The purchased intangible assets are being amortized on a straight-line basis over their estimated useful lives, which are three to nine years for subscriber relationships, two to five years for non-competition agreements and one to four years for technology and other.
Impairment of Long-Lived Assets	*Impairment of Long-Lived Assets* We review our long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. The carrying amount of a long-lived asset is not recoverable if the carrying amount of an asset group exceeds the sum of the undiscounted cash flows expected to result from the use and eventual disposition of the assets at the date it is tested for recoverability, whether in use or under development. An impairment loss is measured as the amount by which the carrying amount of a long-lived asset exceeds its fair value.
Revenue Recognition	*Revenue Recognition* We generate revenues by providing a number of solutions to our customers. These solutions include Trading Partner Fulfillment, Trading Partner Enablement and Trading Partner Analytics. Our cloud-based solutions allow customers to meet their supply chain management requirements. Sales taxes are presented on a net basis within revenue. Revenues are recognized when all of the following criteria are met: (1) persuasive evidence of an arrangement exists, (2) delivery has occurred, (3) the fee is fixed or determinable, and (4) collectability is probable. If collection is not considered probable, revenues are recognized when the fees are collected. Fees related to our Trading Partner Fulfillment and Trading Partner Analytics solutions consist of two revenue sources: set-up fees and recurring monthly fees. Set-up fees are specific for each connection a customer has with a trading partner and most of our customers have connections with numerous trading partners. Set-up fees are nonrefundable upfront fees that do not have standalone value to our customer and are not separable from the recurring monthly fees. All set-up fees and related costs are deferred and recognized ratably over the average life of the connection between the customer and the trading partner, which is approximately two years. We begin recognizing set-up fee revenue once the connection is established. Set-up fees for which connections have not yet been established are classified as long-term. We continue to evaluate the length of the amortization period as more experience is gained with cancellations and technology changes requested by our customers. It is possible that, in the future, the period over which such subscription set-up fees and costs are amortized may be adjusted. Any change in our estimate of the average connection life will affect our future results of operations. The recurring monthly fees are comprised of both fixed and transaction-based fees that are recognized as earned.
Stock-Based Compensation	*Stock-Based Compensation* We recognize the cost of all share-based payments to employees, including grants of employee stock options, in the financial statements based on the grant date fair value of those awards. This cost is recognized over the period for which an employee is required to provide service in exchange for the award. Benefits associated with tax deductions in excess of recognized compensation expense are reported as a cash flow from financing activities. We estimate the fair value of options granted using the Black-Scholes option pricing model. The estimation of stock awards that will ultimately vest requires judgment, and to the extent actual results differ from our estimates, such amounts will be recorded as an adjustment in the period estimates are revised. In valuing share-based awards, judgment is required in determining the expected volatility of common stock and the expected term individuals will hold their share-based awards prior to exercising. The expected volatility of the options is based on the historical volatility of our common stock. The expected term of the options is based on the simplified method which does not consider historical employee exercise behavior.
Advertising Costs	*Advertising Costs* Advertising costs are charged to expense as incurred. Advertising costs were approximately $61,000, $47,000, and $23,000 for the years ended December 31, 2016, 2015 and 2014, respectively. Advertising costs are included in sales and marketing expenses in our consolidated statements of comprehensive income.
Income Taxes	*Income Taxes* We account for income taxes using the liability method, which requires recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the consolidated financial statements. Under this method, deferred tax assets and liabilities are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Deferred tax assets are reduced by a valuation allowance when it is not “more likely than not” that the deferred tax asset will be utilized. We assess our ability to realize our deferred tax assets at the end of each reporting period. Realization of our deferred tax assets is contingent upon future taxable earnings. Accordingly, this assessment requires significant estimates and judgment. If the estimates of future taxable income vary from actual results, our assessment regarding the realization of these deferred tax assets could change. Future changes in the estimated amount of deferred taxes expected to be realized will be reflected in our consolidated financial statements in the period the estimate is changed, with a corresponding adjustment to our operating results. We recognize the financial statement benefit of a tax position only after determining that the relevant tax authority would “more likely than not” sustain the position following an audit. For tax positions meeting the “more likely than not” threshold, the amount recognized in the financial statements is the largest benefit that has a greater than 50% likelihood of being realized upon ultimate settlement with the relevant tax authority.
Net Income Per Share	*Net Income Per Share* Basic net income per share has been computed using the weighted average number of shares of common stock outstanding during each period. Diluted net income per share also includes the impact of our outstanding potential common shares, including options, restricted stock units and restricted stock awards. Potential common shares that are anti-dilutive are excluded from the calculation of diluted net income per share.
Recent Accounting Pronouncements	*Recent Accounting Pronouncements* In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (Topic 606), which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. This guidance will replace most existing revenue recognition guidance in GAAP when it becomes effective. These new requirements are effective for annual reporting periods beginning after December 15, 2017, and interim periods within those annual periods. We do not believe the new revenue recognition standard will materially impact our recognition of the primary fees received from customers for our cloud-based supply chain solutions. We believe the adoption of the new standard could impact our accounting for certain upfront set-up fees and the periods over which the related revenues are recognized, as well as the timing of cost recognition for sales commissions and other contract acquisition costs. We are currently evaluating implementation methods and the extent of the impact that implementation of this standard will have on our consolidated financial statements upon adoption In November 2015, the FASB issued ASU No. 2015-17, Balance Sheet Classification of Deferred Taxes, which amends the guidance requiring companies to separate deferred income tax liabilities and assets into current and non-current amounts in a classified statement of financial position. This accounting guidance simplifies the presentation of deferred income taxes, such that deferred tax liabilities and assets be classified as non-current in a classified statement of financial position. This accounting guidance is effective for us beginning in the first quarter of 2017, but we elected to early adopt this guidance prospectively as of December 31, 2015. As a result, we have classified all deferred tax liabilities and assets as non-current in the condensed consolidated balance sheet as of December 31, 2016 and December 31, 2015. In February 2016, the FASB issued ASU 2016-02, Leases which will supersede the existing lease guidance and will require all leases with a term greater than 12 months to be recognized in the statements of financial position and eliminate current real estate-specific lease guidance, while maintaining substantially similar classification criteria for distinguishing between finance leases and operating leases. This standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018, with early adoption permitted. We believe the adoption of the new lease accounting standard will materially impact our consolidated financial statements by increasing our non-current assets and non-current liabilities on our consolidated balance sheets in order to record the right of use assets and related lease liabilities for our existing operating leases. We are in the process of determining the financial statement impact and are currently unable to estimate the impact on our consolidated financial statements. In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting, which permits entities to make an accounting policy election related to how forfeitures will impact the recognition of compensation cost for stock-based compensation, and also eliminates the requirement that excess tax benefits be realized as a reduction in current taxes payable before the associated tax benefit can be recognized as an increase in paid in capital. This standard is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2016, with early adoption permitted. We expect that our previously unrecognized federal and state net operating losses ($46.2 million and $10.7 million, respectively, as of December 31, 2016) will be included in the deferred tax assets recognized in our consolidated balance sheets on a modified retrospective basis as of January 1, 2017. With the adoption of ASU 2016-09 we will also be required to present excess tax benefits as an operating activity in the same manner as other cash flows related to income taxes on the statement of cash flows rather than as a financing activity.

Business Acquisitions (Tables)

12 Months Ended

Dec. 31, 2016

Toolbox Solutions, Inc. [Member]

Business Purchase Price

The purchase price consisted of the following (in thousands):


Cash	$	18,032
SPS Commerce, Inc. common stock		2,922
Fair value of share-based earn-out liability		1,043

	$	21,997

Estimated Fair Values of Assets Acquired, Net of Cash Acquired and Liabilities Assumed at Acquisition Date

The following table summarizes the estimated fair values of the assets acquired, net of cash acquired of $359,000, and liabilities assumed at the acquisition date (in thousands):


Current assets	$	1,253
Property and equipment		56
Goodwill		15,389
Intangible assets		9,070
Current liabilities		(1,249	)
Deferred revenue		(301	)
Deferred income tax liability		(2,221	)

	$	21,997

Estimated Fair Value of Purchased Intangible Assets and Estimated Useful Lives

The following table summarizes the estimated fair value of the purchased intangible assets and their estimated useful lives:


Purchased Intangible Assets	Estimated Fair Value (in thousands)		Estimated Life (in years)
Subscriber relationships	$	7,400		8
Developed technology		1,200		4
Trade names		70		1
Non-competition agreements		400		5

Total	$	9,070

Pro Forma Financial Information


	Year Ended December 31,
(in thousands, except per share data)	2016		2015
Pro forma total revenue	$	193,525	$	166,873
Pro forma net income		5,976		2,400
Pro forma net income per share
Basic		0.35		0.14
Diluted		0.35		0.14

Leadtec [Member]

Business Purchase Price

The purchase price consisted of the following (in thousands):


Cash	$	12,595
SPS Commerce, Inc. common stock		2,203

	$	14,798

Estimated Fair Values of Assets Acquired, Net of Cash Acquired and Liabilities Assumed at Acquisition Date

The following table summarizes the estimated fair values of the assets acquired and liabilities assumed at the acquisition date (in thousands):


Current and other assets	$	659
Property and equipment		143
Goodwill		9,954
Intangible assets		4,891
Current liabilities		(849	)

	$	14,798

Estimated Fair Value of Purchased Intangible Assets and Estimated Useful Lives

The following table summarizes the estimated fair value of the purchased intangible assets and their estimated useful lives:


Purchased Intangible Assets	Estimated Fair Value (in thousands)		Estimated Life (in years)
Subscriber relationships	$	3,778		9
Non-competition agreements		148		5
Technology and other		965		2.5

Total	$	4,891

Pro Forma Financial Information


	Year Ended December 31,
(in thousands, except per share data)	2014
Pro forma total revenue	$	132,818
Pro forma net income		2,973
Pro forma net income per share
Basic		0.18
Diluted		0.18

Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2016

Investments, Debt and Equity Securities [Abstract]

Summary of Investment in Cash Equivalents and Marketable Securities

Cash equivalents and marketable securities, consisted of the following (in thousands):


	December 31,
	2016							2015
	Amortized Cost		Unrealized Gains (Losses)			Fair Value		Amortized Cost		Unrealized Gains (Losses)			Fair Value
Cash equivalents:
Money market funds	$	75,375	$	—		$	75,375	$	79,717	$	—		$	79,717
Marketable securities:
Corporate bonds		15,681		(96	)		15,585		10,042		(34	)		10,008
Commercial paper		4,977		10			4,987		2,499		1			2,500
U.S. treasury securities		7,489		10			7,499		7,489		(27	)		7,462
U.S. agency obligations		2,497		3			2,500		2,497		1			2,498

	$	106,019	$	(73	)	$	105,946	$	102,244	$	(59	)	$	102,185

Due within one year						$	98,452						$	87,235
Due within two years							7,494							14,950

Total						$	105,946						$	102,185

Summary of Financial Assets Measured at Fair Value on a Recurring Basis


	Level 1		Level 2		Level 3		Total
Assets at December 31, 2016:
Cash and cash equivalents:
Money market funds	$	75,375	$	—	$	—	$	75,375
Marketable securities:
Corporate bonds		—		15,585		—		15,585
Commerical paper		—		4,987		—		4,987
U.S. treasury securities		—		7,499		—		7,499
U.S. agency obligations		—		2,500		—		2,500

	$	75,375	$	30,571	$	—	$	105,946

Assets at December 31, 2015:
Cash and cash equivalents:
Money market funds	$	79,717	$	—	$	—	$	79,717
Marketable securities:
Corporate bonds		—		10,008		—		10,008
Commerical paper		—		2,500		—		2,500
U.S. treasury securities		—		7,462		—		7,462
U.S. agency obligations		—		2,498		—		2,498

	$	79,717	$	22,468	$	—	$	102,185

- Definition

Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities.

+ References + Details

Allowance for Doubtful Accounts (Tables)

12 Months Ended

Dec. 31, 2016

Text Block [Abstract]

Schedule of Allowance for Doubtful Activity Included in Accounts Receivable Net

The allowance for doubtful accounts activity, included in accounts receivable, net, was as follows (in thousands):


	2016			2015			2014
Balances, January 1	$	446		$	279		$	237
Provision for doubtful accounts		1,375			1,271			717
Write-offs, net of recoveries		(1,306	)		(1,104	)		(675	)

Balances, December 31	$	515		$	446		$	279

Property and Equipment, net (Tables)

12 Months Ended

Dec. 31, 2016

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment, Net

Property and equipment, net included the following (in thousands):


	December 31,
	2016			2015
Computer equipment and software	$	29,270		$	27,725
Office equipment and furniture		7,087			5,793
Leasehold improvements		7,844			5,530

		44,201			39,048
Less: accumulated depreciation and amortization		(28,887	)		(25,428	)

	$	15,314		$	13,620

Goodwill and Intangible Assets, net (Tables)

12 Months Ended

Dec. 31, 2016

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Changes in Net Carrying Amount of Goodwill

The changes in the net carrying amount of goodwill for the years ended December 31, 2016 and 2015 are as follows (in thousands):


	2016		2015
Balances, January 1	$	33,848	$	34,854
Additions from business acquisitions		15,389		—
Foreign currency translation		540		(1,006	)

Balances, December 31	$	49,777	$	33,848

Intangible Assets

Intangible assets, net included the following (in thousands):


	December 31, 2016
	Carrying Amount		Accumulated Amortization			Foreign Currency Translation		Net
Subscriber relationships	$	33,736	$	(15,708	)	$	295	$	18,323
Non-competition agreements		2,234		(1,818	)		17		433
Technology and other		2,089		(1,120	)		63		1,032

	$	38,059	$	(18,646	)	$	375	$	19,788


	December 31, 2015
	Carrying Amount		Accumulated Amortization			Foreign Currency Translation			Net
Subscriber relationships	$	26,701	$	(11,856	)	$	(364	)	$	14,481
Non-competition agreements		1,843		(1,653	)		(9	)		181
Technology and other		905		(400	)		(86	)		419

	$	29,449	$	(13,909	)	$	(459	)	$	15,081

Future Amortization Expense for Intangible Assets

At December 31, 2016, future amortization expense for intangible assets was as follows (in thousands):


2017	$	4,380
2018		3,793
2019		3,502
2020		3,174
2021		2,381
Thereafter		2,558

	$	19,788

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2016

Commitments and Contingencies Disclosure [Abstract]

Future Minimum Payments Under Operating Leases

At December 31, 2016, our future minimum payments under operating leases were as follows (in thousands):


2017	$	3,318
2018		3,123
2019		3,220
2020		1,825
2021		1,047
Thereafter		1,174

	$	13,707

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2016

Stock-Based Compensation Expense

This expense was allocated as follows (in thousands):


	Year Ended December 31,
	2016		2015		2014
Cost of revenues	$	1,309	$	989	$	614
Operating expenses
Sales and marketing		2,412		1,978		1,933
Research and development		618		640		444
General and administrative		3,684		2,772		2,405

Total stock-based compensation expense	$	8,023	$	6,379	$	5,396

Stock Option Activity

Our stock option activity was as follows:


	Options (#)			Weighted Average Exercise Price ($/share)
Outstanding at January 1, 2014		1,097,223		$	19.62
Granted		153,770			62.86
Exercised		(153,196	)		12.27
Forfeited		(12,334	)		41.38

Outstanding at December 31, 2014		1,085,463			26.53
Granted		181,487			67.50
Exercised		(305,106	)		14.55
Forfeited		(18,741	)		45.82

Outstanding at December 31, 2015		943,103			37.91
Granted		340,609			48.58
Exercised		(221,630	)		19.42
Forfeited		(46,070	)		55.58

Outstanding at December 31, 2016		1,016,012			44.72

Weighted Average Fair Value Per Share of Options Granted, Assumptions


	Year Ended December 31,
	2016			2015			2014
Volatility		38	%		39	%		42	%
Dividend yield		—			—			—
Life (in years)		4.54			4.52			4.17
Risk-free interest rate		1.19	%		1.36	%		1.44	%

Fair Value Estimation of Common Stock Using Black-Scholes Option Pricing Model, Weighted-Average Assumptions

The fair value was estimated based on the market price of our common stock at the beginning of each offering period and using the Black-Scholes option pricing model with the following weighted-average assumptions:


	Year Ended December 31,
	2016			2015			2014
Volatility		37	%		30	%		45	%
Dividend yield		—			—			—
Life (in years)		0.50			0.50			0.50
Risk-free interest rate		0.42	%		0.12	%		0.08	%

Restricted Stock Units [Member]

Restricted Stock Units and Restricted Stock Awards

Our restricted stock units activity was as follows:


	Restricted Stock Units (#)			Weighted Average Grant Date Fair Value ($/share)
Outstanding at January 1, 2014		102,644		$	33.77
Granted		42,001			64.89
Vested and common stock issued		(28,367	)		32.92
Forfeited		(1,145	)		35.42

Outstanding at December 31, 2014		115,133			45.25
Granted		68,159			67.50
Vested and common stock issued		(37,669	)		40.91
Forfeited		(5,058	)		54.28

Outstanding at December 31, 2015		140,565			56.88
Granted		115,896			48.32
Vested and common stock issued		(52,133	)		48.19
Forfeited		(15,286	)		55.48

Outstanding at December 31, 2016		189,042			54.14

Restricted Stock Award [Member]

Restricted Stock Units and Restricted Stock Awards

Our restricted stock awards activity was as follows:


	Restricted Stock Awards (#)			Weighted Average Grant Date Fair Value ($/share)
Outstanding at January 1, 2014		1,422		$	48.66
Restricted common stock issued		5,352			51.74
Restrictions lapsed		(5,199	)		51.04
Forfeited		(237	)		48.66

Outstanding at December 31, 2014		1,338			51.74
Restricted common stock issued		4,110			67.37
Restrictions lapsed		(4,416	)		62.63
Forfeited		—			—

Outstanding at December 31, 2015		1,032			67.39
Restricted common stock issued		6,078			52.27
Restrictions lapsed		(5,586	)		55.06
Forfeited		—			—

Outstanding at December 31, 2016		1,524			52.28

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Schedule of Provision for Income Taxes

The provision for income taxes was as follows (in thousands):


	Year Ended December 31,
	2016			2015			2014
Current
Federal	$	3,684		$	2,066		$	43
State		555			289			254
Foreign		599			119			80
Deferred
Federal		(988	)		103			1,183
State		(133	)		(141	)		(152	)
Foreign		(577	)		—			—

	$	3,140		$	2,436		$	1,408

Reconciliation of the Provision for Income Taxes to the Statutory Federal Rate

A reconciliation of the expected federal income tax at the statutory rate to the provision for income taxes was as follows (in thousands):


	Year Ended December 31,
	2016			2015			2014
Expected federal income tax at statutory rate	$	3,011		$	2,404		$	1,398
State income taxes, net of federal tax effect		320			246			124
Tax impact of foreign activity		(115	)		39			37
Permanent book/tax differences		372			67			173
Change in valuation allowance		(35	)		(27	)		(88	)
Change in state deferred rate		(67	)		(118	)		(9	)
Research and development credit		(261	)		(200	)		(178	)
Other		(85	)		25			(49	)

Total provision for income taxes	$	3,140		$	2,436		$	1,408

Significant Components of Deferred Tax Assets (Liabilities)

The significant components of our deferred tax assets (liabilities) were as follows (in thousands):


	December 31,
	2016						2015
Deferred tax assets
Net operating loss and credit carryforwards	$	4,614					$	4,687
Deferred operations		799						1,443
Stock-based compensation expense		4,085						3,284
Depreciation and amortization		—						1,179
Accounts receivable allowances		363						252
Accrued expenses		2,704						1,137
Other		297						234

Gross deferred tax asset					12,862						12,216
Less: valuation allowance		(649	)					(928	)

Total net deferred tax asset					12,213						11,288
Deferred tax liability
Foreign operations		(350	)					(139	)
Depreciation and amortization		(1,328	)					—

Total deferred tax liability					(1,678	)					(139	)

Net deferred tax assets				$	10,535					$	11,149

Net Income Per Share (Tables)

12 Months Ended

Dec. 31, 2016

Earnings Per Share [Abstract]

Components of Computation of Basic and Diluted Net Income Per Share

The following table presents the components of the computation of basic and diluted net income per share for the periods indicated (in thousands, except per share amounts):


	Year Ended December 31,
	2016		2015		2014
Numerator
Net income	$	5,710	$	4,639	$	2,704
Denominator
Weighted average common shares outstanding, basic		16,947		16,565		16,236
Options to purchase common stock		267		437		535
Restricted stock units		27		27		42
Employee stock purchase plan		—		3		1

Weighted average common shares outstanding, diluted		17,241		17,032		16,814

Net income per share
Basic	$	0.34	$	0.28	$	0.17
Diluted	$	0.33	$	0.27	$	0.16

Selected Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2016

Quarterly Financial Information Disclosure [Abstract]

Summary of Unaudited Quarterly Statements of Comprehensive Income Data

The following table presents our selected unaudited quarterly statements of comprehensive income data (in thousands, except per share amounts):


	For the Three Months Ended
2016	Mar 31		Jun 30		Sep 30		Dec 31
Revenues	$	45,599	$	47,351	$	49,284	$	51,061
Gross profit		30,718		31,379		33,113		33,739
Income from operations		1,314		880		2,670		2,653
Net income		1,044		352		2,509	$	1,805
Diluted earnings per share	$	0.06	$	0.02	$	0.14	$	0.10


	For the Three Months Ended
2015	Mar 31		Jun 30		Sep 30		Dec 31
Revenues	$	36,970	$	38,846	$	40,354	$	42,348
Gross profit		25,398		26,511		27,654		28,912
Income from operations		922		1,027		2,260		2,814
Net income		586		651		1,270		2,132
Diluted earnings per share	$	0.03	$	0.04	$	0.07	$	0.12

General - Additional Information (Detail)	12 Months Ended
General - Additional Information (Detail)	Dec. 31, 2016 USD ($) Segment	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Schedule Of Accounting Policies [Line Items]
Number of reportable segments \| Segment	1
Expected life of customer relationship period	2 years
Advertising costs	$ 61,000	$ 47,000	$ 23,000
Unrecognized federal and state net operating losses	4,614,000	$ 4,687,000
Domestic Tax Authority [Member]
Schedule Of Accounting Policies [Line Items]
Unrecognized federal and state net operating losses	46,200,000
State and Local Jurisdiction [Member]
Schedule Of Accounting Policies [Line Items]
Unrecognized federal and state net operating losses	$ 10,700,000
Computer Equipment and Software [Member] \| Maximum [Member]
Schedule Of Accounting Policies [Line Items]
Estimated useful lives of property and equipment	3 years
Computer Equipment and Software [Member] \| Minimum [Member]
Schedule Of Accounting Policies [Line Items]
Estimated useful lives of property and equipment	2 years
Office Equipment and Furniture [Member] \| Maximum [Member]
Schedule Of Accounting Policies [Line Items]
Estimated useful lives of property and equipment	7 years
Office Equipment and Furniture [Member] \| Minimum [Member]
Schedule Of Accounting Policies [Line Items]
Estimated useful lives of property and equipment	5 years
Subscriber Relationships [Member] \| Maximum [Member]
Schedule Of Accounting Policies [Line Items]
Estimated useful lives of intangible assets	9 years
Subscriber Relationships [Member] \| Minimum [Member]
Schedule Of Accounting Policies [Line Items]
Estimated useful lives of intangible assets	3 years
Non-competition Agreements [Member] \| Maximum [Member]
Schedule Of Accounting Policies [Line Items]
Estimated useful lives of intangible assets	5 years
Non-competition Agreements [Member] \| Minimum [Member]
Schedule Of Accounting Policies [Line Items]
Estimated useful lives of intangible assets	2 years
Technology and Other [Member] \| Maximum [Member]
Schedule Of Accounting Policies [Line Items]
Estimated useful lives of intangible assets	4 years
Technology and Other [Member] \| Minimum [Member]
Schedule Of Accounting Policies [Line Items]
Estimated useful lives of intangible assets	1 year

Business Acquisitions - Additional Information (Detail) - USD ($)			3 Months Ended		12 Months Ended
	Jan. 05, 2016	Oct. 12, 2014	Dec. 31, 2016	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Oct. 10, 2014
Business Acquisition [Line Items]
Stock issued for acquisition					$ 2,922,000		$ 2,203,000
Amortization expense for purchased intangible assets					4,738,000	$ 3,307,000	2,856,000
Contingent Consideration Liability [Member]
Business Acquisition [Line Items]
Other income					1,100,000
Toolbox Solutions, Inc. [Member]
Business Acquisition [Line Items]
Payments to acquire business	$ 18,000,000
Stock issued for acquisition	$ 2,900,000				$ 2,922,000
Stock issued for acquisition, Shares	43,953				43,953
Number of shares of common stock issuable	16,222
Cash Acquired from Acquisition	$ 359,000
Number of gross shares issued	48,668		48,668		48,668
Number of shares retuned from escrow			4,715		4,715
Amortization expense for purchased intangible assets					$ 1,400,000
Acquisition-related cost included in consolidated statements					147,000
Revenues from acquisition					7,900,000
Proforma adjustments in amortization					$ 1,400,000
Statutory blended income tax rate					26.50%
Fair value of the shares issued	$ 2,900,000
Leadtec [Member]
Business Acquisition [Line Items]
Payments to acquire business		$ 12,600,000
Stock issued for acquisition					$ 2,203,000
Stock issued for acquisition, Shares		43,595			43,595
Amortization expense for purchased intangible assets				$ 168,000		$ 733,000
Acquisition-related cost included in consolidated statements							690,000
Revenues from acquisition				1,200,000
Fair value of the shares issued								$ 2,200,000
Acquisition related one-time Australian stamp duty tax							$ 338,000
Operating loss from acquisition				$ (280,000)

Business Acquisitions - Business Purchase Price (Detail) - USD ($) $ in Thousands		12 Months Ended
	Jan. 05, 2016	Dec. 31, 2016	Dec. 31, 2014
Business Acquisition [Line Items]
Cash		$ 18,032	$ 12,595
SPS Commerce, Inc. common stock		2,922	$ 2,203
Toolbox Solutions, Inc. [Member]
Business Acquisition [Line Items]
Cash		18,032
SPS Commerce, Inc. common stock	$ 2,900	2,922
Fair value of share-based earn-out liability		1,043
Total purchase price		21,997
Leadtec [Member]
Business Acquisition [Line Items]
Cash		12,595
SPS Commerce, Inc. common stock		2,203
Total purchase price		$ 14,798

Business Acquisitions - Estimated Fair Values of the Assets Acquired, Net of Cash acquired and Liabilities Assumed at the Acquisition Date (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
GOODWILL	$ 49,777	$ 33,848	$ 34,854
Toolbox Solutions, Inc. [Member]
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
Current assets	1,253
Property and equipment	56
GOODWILL	15,389
Intangible assets	9,070
Current liabilities	(1,249)
Deferred revenue	(301)
Deferred income tax liability	(2,221)
Total purchase price	21,997
Leadtec [Member]
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
Current and other assets	659
Property and equipment	143
GOODWILL	9,954
Intangible assets	4,891
Current liabilities	(849)
Total purchase price	$ 14,798

Business Acquisitions - Estimated Fair Value of Purchased Intangible Assets and Estimated Useful Lives (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($)
Toolbox Solutions, Inc. [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 9,070
Toolbox Solutions, Inc. [Member] \| Subscriber Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 7,400
Estimated Life (in years)	8 years
Toolbox Solutions, Inc. [Member] \| Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 1,200
Estimated Life (in years)	4 years
Toolbox Solutions, Inc. [Member] \| Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 70
Estimated Life (in years)	1 year
Toolbox Solutions, Inc. [Member] \| Non-competition Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 400
Estimated Life (in years)	5 years
Leadtec [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 4,891
Leadtec [Member] \| Subscriber Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 3,778
Estimated Life (in years)	9 years
Leadtec [Member] \| Non-competition Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 148
Estimated Life (in years)	5 years
Leadtec [Member] \| Technology and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 965
Estimated Life (in years)	2 years 6 months

Business Acquisitions - Pro Forma Financial Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Toolbox Solutions, Inc. [Member]
Business Acquisition [Line Items]
Pro forma total revenue	$ 193,525	$ 166,873
Pro forma net income	$ 5,976	$ 2,400
Pro forma net income per share, Basic	$ 0.35	$ 0.14
Pro forma net income per share, Diluted	$ 0.35	$ 0.14
Leadtec [Member]
Business Acquisition [Line Items]
Pro forma total revenue			$ 132,818
Pro forma net income			$ 2,973
Pro forma net income per share, Basic			$ 0.18
Pro forma net income per share, Diluted			$ 0.18

Financial Instruments - Summary of Investment in Cash Equivalents and Marketable Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Cash Equivalents and Marketable Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 106,019	$ 102,244
Due within one year	98,452	87,235
Unrealized Gains (Losses)	(73)	(59)
Due within two years	7,494	14,950
Fair Value	105,946	102,185
Money Market Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	75,375	79,717
Fair Value	75,375	79,717
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	15,681	10,042
Unrealized Gains (Losses)	(96)	(34)
Fair Value	15,585	10,008
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	4,977	2,499
Unrealized Gains (Losses)	10	1
Fair Value	4,987	2,500
U.S. Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	7,489	7,489
Unrealized Gains (Losses)	10	(27)
Fair Value	7,499	7,462
U.S. Agency Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,497	2,497
Unrealized Gains (Losses)	3	1
Fair Value	$ 2,500	$ 2,498

Financial Instruments - Additional Information (Detail)	Dec. 31, 2016 USD ($)
Money Market Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unrealized Losses	$ 0

Financial Instruments - Summary of Financial Assets Measured at Fair Value on a Recurring Basis (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets fair value	$ 105,946	$ 102,185
Money Market Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets fair value	75,375	79,717
Corporate Bonds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets fair value	15,585	10,008
Commercial Paper [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets fair value	4,987	2,500
U.S. Treasury Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets fair value	7,499	7,462
U.S. Agency Obligations [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets fair value	2,500	2,498
Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets fair value	75,375	79,717
Level 1 [Member] \| Money Market Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets fair value	75,375	79,717
Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets fair value	30,571	22,468
Level 2 [Member] \| Corporate Bonds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets fair value	15,585	10,008
Level 2 [Member] \| Commercial Paper [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets fair value	4,987	2,500
Level 2 [Member] \| U.S. Treasury Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets fair value	7,499	7,462
Level 2 [Member] \| U.S. Agency Obligations [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets fair value	$ 2,500	$ 2,498

Allowance for Doubtful Accounts - Schedule of Allowance for Doubtful Activity Included in Accounts Receivable Net (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Receivables [Abstract]
Beginning Balance	$ 446	$ 279	$ 237
Provision for doubtful accounts	1,375	1,271	717
Write-offs, net of recoveries	(1,306)	(1,104)	(675)
Ending Balance	$ 515	$ 446	$ 279

Property and Equipment, net - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 44,201	$ 39,048
Less: accumulated depreciation and amortization	(28,887)	(25,428)
Net, Total	15,314	13,620
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	29,270	27,725
Office Equipment and Furniture [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	7,087	5,793
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 7,844	$ 5,530

Property and Equipment, net - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Property Plant and Equipment Useful Life and Values [Abstract]
Property and equipment held at subsidiary and office locations outside of the United States of America, net	$ 2,100,000	$ 709,000.0

Goodwill and Intangible Assets Net - Schedule of Changes in Net Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Balances, January 1	$ 33,848	$ 34,854
Additions from business acquisitions	15,389
Foreign currency translation	540	(1,006)
Balances, December 31	$ 49,777	$ 33,848

Goodwill and Intangible Assets, net - Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Carrying Amount	$ 38,059	$ 29,449
Accumulated Amortization	(18,646)	(13,909)
Foreign Currency Translation	375	(459)
Net	19,788	15,081
Subscriber Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Carrying Amount	33,736	26,701
Accumulated Amortization	(15,708)	(11,856)
Foreign Currency Translation	295	(364)
Net	18,323	14,481
Non-competition Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Carrying Amount	2,234	1,843
Accumulated Amortization	(1,818)	(1,653)
Foreign Currency Translation	17	(9)
Net	433	181
Technology and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Carrying Amount	2,089	905
Accumulated Amortization	(1,120)	(400)
Foreign Currency Translation	63	(86)
Net	$ 1,032	$ 419

Goodwill and Intangible Assets, net - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense	$ 4,738	$ 3,307	$ 2,856

Goodwill and Intangible Assets, net - Future Amortization Expense for Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
2017	$ 4,380
2018	3,793
2019	3,502
2020	3,174
2021	2,381
Thereafter	2,558
Net	$ 19,788	$ 15,081

Commitments and Contingencies - Additional Information (Detail) $ in Millions				12 Months Ended
	Jun. 30, 2016 OptionPlan	Sep. 01, 2015 OptionPlan	Feb. 14, 2012 OptionPlan	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Rent expense charged to operations \| $				$ 5.0	$ 4.6	$ 3.7
Lease agreement expires, date	Dec. 31, 2021	Jun. 30, 2023	Apr. 30, 2020
Number of options to extend term of the lease \| OptionPlan	1	1	2
Options to extend the term of the lease, number of years	5 years	5 years	3 years

Commitments and Contingencies - Future Minimum Payments Under Operating Leases (Detail) $ in Thousands	Dec. 31, 2016 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2017	$ 3,318
2018	3,123
2019	3,220
2020	1,825
2021	1,047
Thereafter	1,174
Operating leases, total	$ 13,707

Stockholders' Equity - Additional Information (Detail) - USD ($) $ in Millions			3 Months Ended	12 Months Ended
	Jan. 05, 2016	Oct. 12, 2014	Dec. 31, 2016	Dec. 31, 2016	Oct. 10, 2014
Leadtec [Member]
Schedule Of Stockholders Equity [Line Items]
Fair value of the shares issued					$ 2.2
Stock issued for acquisition, Shares		43,595		43,595
Toolbox Solutions, Inc. [Member]
Schedule Of Stockholders Equity [Line Items]
Number of gross shares issued	48,668		48,668	48,668
Fair value of the shares issued	$ 2.9
Stock issued for acquisition, Shares	43,953			43,953
Number of shares retuned from escrow			4,715	4,715

Stock-Based Compensation - Additional Information (Detail)	1 Months Ended	12 Months Ended
	Feb. 29, 2016 shares	Dec. 31, 2016 USD ($) OfferingPeriods $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant \| shares		3,900,000
Stock-based compensation expense		$ 8,023,000	$ 6,379,000	$ 5,396,000
Unrecognized stock-based compensation expense		$ 13,700,000
Unrecognized stock-based compensation, expected to be recognized, weighted average period		2 years 6 months 22 days
Stock options vest, period		4 years
Stock options contractual term, from the date of grant		Seven to ten years
Stock options exercisable \| shares		582,650
Weighted average exercise price \| $ / shares		$ 38.43
Weighted average remaining contractual life		4 years 7 months 6 days
Fair value of options vested		$ 3,400,000	3,100,000	2,900,000
Intrinsic value of options exercised		8,600,000	16,800,000	7,400,000
Intrinsic value of options outstanding		$ 25,600,000	$ 30,500,000	$ 33,800,000
Weighted average fair value per share of options granted \| $ / shares		$ 16.13	$ 23.09	$ 24.36
Number of RSU's vested and not issued during the period \| shares		34,190
Percentage of common stock on fair market value		85.00%
Number of offerings per year \| OfferingPeriods		2
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 552,000	$ 408,000	$ 473,000
Common stock reserved for future issuance \| shares		1,100,000
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options vest, period		4 years
Restricted Stock Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards units vest over, period		1 year
Equity Incentive Plan [Member] \| 2010 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares were authorized under 2010 Equity Incentive Plan \| shares	1,003,439
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee stock purchase plan, employees contribution		$ 1,700,000	$ 1,500,000	$ 1,300,000
Employee stock purchase plan, shares purchased \| shares		33,357	28,362	26,353
Maximum [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options contractual term range		10 years
Minimum [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options contractual term range		7 years

Stock-Based Compensation - Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 8,023	$ 6,379	$ 5,396
Cost of Revenues [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	1,309	989	614
Sales and Marketing [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	2,412	1,978	1,933
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	618	640	444
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 3,684	$ 2,772	$ 2,405

Stock-Based Compensation - Stock Option Activity (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Options Outstanding, Beginning balance	943,103	1,085,463	1,097,223
Options, Granted	340,609	181,487	153,770
Options, Exercised	(221,630)	(305,106)	(153,196)
Options, Forfeited	(46,070)	(18,741)	(12,334)
Options Outstanding, Ending balance	1,016,012	943,103	1,085,463
Weighted Average Exercise Price, Outstanding, Beginning Balance	$ 37.91	$ 26.53	$ 19.62
Weighted Average Exercise Price, Granted	48.58	67.50	62.86
Weighted Average Exercise Price, Exercised	19.42	14.55	12.27
Weighted Average Exercise Price, Forfeited	55.58	45.82	41.38
Weighted Average Exercise Price, Outstanding, Ending Balance	$ 44.72	$ 37.91	$ 26.53

Stock-Based Compensation - Weighted Average Fair Value Per Share of Options Granted, Assumptions (Detail) - Stock Options [Member]	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility	38.00%	39.00%	42.00%
Dividend yield	0.00%	0.00%	0.00%
Life (in years)	4 years 6 months 15 days	4 years 6 months 7 days	4 years 2 months 1 day
Risk-free interest rate	1.19%	1.36%	1.44%

Stock-Based Compensation - Restricted Stock Units (Detail) - Restricted Stock Units [Member] - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, Outstanding, Beginning Balance	140,565	115,133	102,644
Granted, stock units	115,896	68,159	42,001
Vested, stock units	(52,133)	(37,669)	(28,367)
Forfeited, stock units	(15,286)	(5,058)	(1,145)
Stock awards, Outstanding, Ending Balance	189,042	140,565	115,133
Weighted average grant date fair value, Outstanding, Beginning Balance	$ 56.88	$ 45.25	$ 33.77
Granted, Weighted Average Grant Date Fair Value	48.32	67.50	64.89
Vested, Weighted Average Grant Date Fair Value	48.19	40.91	32.92
Forfeited, Weighted Average Grant Date Fair Value	55.48	54.28	35.42
Weighted average grant date fair value, Outstanding, Ending Balance	$ 54.14	$ 56.88	$ 45.25

Stock-Based Compensation - Restricted Stock Awards (Detail) - Restricted Stock Award [Member] - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, Outstanding, Beginning Balance	1,032	1,338	1,422
Restricted common stock issued, stock awards	6,078	4,110	5,352
Restrictions lapsed, stock awards	(5,586)	(4,416)	(5,199)
Forfeited, stock awards			(237)
Stock awards, Outstanding, Ending Balance	1,524	1,032	1,338
Weighted average grant date fair value, Outstanding, Beginning Balance	$ 67.39	$ 51.74	$ 48.66
Restricted common stock issued, Weighted Average Grant Date Fair Value	52.27	67.37	51.74
Restrictions lapsed, Weighted Average Grant Date Fair Value	55.06	62.63	51.04
Forfeited, Weighted Average Grant Date Fair Value			48.66
Weighted average grant date fair value, Outstanding, Ending Balance	$ 52.28	$ 67.39	$ 51.74

Stock-Based Compensation - Fair Value Estimation of Common Stock Using Black-Scholes Option Pricing Model, Weighted-Average Assumptions (Detail) - Employee Stock Purchase Plan [Member]	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility	37.00%	30.00%	45.00%
Dividend yield	0.00%	0.00%	0.00%
Life (in years)	6 months	6 months	6 months
Risk-free interest rate	0.42%	0.12%	0.08%

Income Taxes - Schedule of Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current
Federal	$ 3,684	$ 2,066	$ 43
State	555	289	254
Foreign	599	119	80
Deferred
Federal	(988)	103	1,183
State	(133)	(141)	(152)
Foreign	(577)
Total provision (benefit) for income taxes	$ 3,140	$ 2,436	$ 1,408

Income Taxes - Reconciliation of Provision for Income Taxes to Statutory Federal Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Expected federal income tax at statutory rate	$ 3,011	$ 2,404	$ 1,398
State income taxes, net of federal tax effect	320	246	124
Tax impact of foreign activity	(115)	39	37
Permanent book/tax differences	372	67	173
Change in valuation allowance	(35)	(27)	(88)
Change in state deferred rate	(67)	(118)	(9)
Research and development credit	(261)	(200)	(178)
Other	(85)	25	(49)
Total provision (benefit) for income taxes	$ 3,140	$ 2,436	$ 1,408

Income Taxes - Significant Components of Deferred Tax Assets (Liabilities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets
Net operating loss and credit carryforwards	$ 4,614	$ 4,687
Deferred operations	799	1,443
Stock-based compensation expense	4,085	3,284
Depreciation and amortization		1,179
Accounts receivable allowances	363	252
Accrued expenses	2,704	1,137
Other	297	234
Gross deferred tax asset	12,862	12,216
Less: valuation allowance	(649)	(928)
Total net deferred tax asset	12,213	11,288
Deferred tax liability
Foreign operations	(350)	(139)
Depreciation and amortization	(1,328)
Total deferred tax liability	(1,678)	(139)
Net deferred tax assets	$ 10,535	$ 11,149

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Income Tax Expense Benefit [Line Items]
Net operating losses	$ 4,614,000	$ 4,687,000
Valuation allowance against our deferred tax assets	649,000
Unrecognized tax benefits	0
Significant change in unrecognized tax benefits is reasonably possible, amount of unrecorded benefit	0
Domestic Tax Authority [Member]
Income Tax Expense Benefit [Line Items]
Net operating loss carry forwards for U. S. federal tax	70,700,000
Unused federal losses that will expire	17,600,000
Maximum annual limitation of federal net operating losses	990,000
Net operating losses	46,200,000
Domestic Tax Authority [Member] \| Research and Development [Member]
Income Tax Expense Benefit [Line Items]
Research and development credit carryforwards	$ 980,000
Research and development credit expire date	2030
Domestic Tax Authority [Member] \| Maximum [Member]
Income Tax Expense Benefit [Line Items]
Expiration of net operating loss carryforwards	Loss carryforwards for federal tax purposes will expire between 2019 and 2036 if not utilized
State and Local Jurisdiction [Member]
Income Tax Expense Benefit [Line Items]
Net operating loss carry forwards for U. S. federal tax	$ 19,200,000
Net operating losses	10,700,000
State and Local Jurisdiction [Member] \| Research and Development [Member]
Income Tax Expense Benefit [Line Items]
Research and development credit carryforwards	$ 461,000
Research and development credit expire date	2025
State and Local Jurisdiction [Member] \| Maximum [Member]
Income Tax Expense Benefit [Line Items]
Expiration of net operating loss carryforwards	Loss carryforwards for state tax purposes will expire between 2017 and 2036 if not utilized

Net Income Per Share - Components of Computation of Basic and Diluted Net Income Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Numerator
Net income	$ 1,805	$ 2,509	$ 352	$ 1,044	$ 2,132	$ 1,270	$ 651	$ 586	$ 5,710	$ 4,639	$ 2,704
Denominator
Weighted average common shares outstanding, basic									16,947	16,565	16,236
Options to purchase common stock									267	437	535
Restricted stock units									27	27	42
Employee stock purchase plan										3	1
Weighted average common shares outstanding, diluted									17,241	17,032	16,814
Net income per share
Basic									$ 0.34	$ 0.28	$ 0.17
Diluted	$ 0.10	$ 0.14	$ 0.02	$ 0.06	$ 0.12	$ 0.07	$ 0.04	$ 0.03	$ 0.33	$ 0.27	$ 0.16

Net Income Per Share - Additional Information (Detail) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share [Abstract]
Outstanding potential common shares excluded from computation of net income per share	5,000	4,000	126,000

Retirement Savings Plan - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Maximum allowable contribution by employee percentage	100.00%
Defined benefit plan employer matching contribution percent	25.00%
Maximum annual contribution per employee, percent	6.00%
Employer matching contribution amount	$ 1,400,000	$ 1,100,000	$ 733,000

Related Party Transactions - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Related Party Transaction [Line Items]
Officers compensation from the foundation	$ 0
Contributions To Related Party [Member]
Related Party Transaction [Line Items]
Contributions to the foundation	250,000	$ 500,000
Legal Obligation To Future Commitments [Member]
Related Party Transaction [Line Items]
Contributions to the foundation	$ 0

Selected Quarterly Financial Data (Unaudited) - Summary of Unaudited Quarterly Statements of Comprehensive Income Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 51,061	$ 49,284	$ 47,351	$ 45,599	$ 42,348	$ 40,354	$ 38,846	$ 36,970	$ 193,295	$ 158,518	$ 127,947
Gross profit	33,739	33,113	31,379	30,718	28,912	27,654	26,511	25,398	128,949	108,475	87,956
Income from operations	2,653	2,670	880	1,314	2,814	2,260	1,027	922	7,517	7,023	4,383
Net income	$ 1,805	$ 2,509	$ 352	$ 1,044	$ 2,132	$ 1,270	$ 651	$ 586	$ 5,710	$ 4,639	$ 2,704
Diluted earnings per share	$ 0.10	$ 0.14	$ 0.02	$ 0.06	$ 0.12	$ 0.07	$ 0.04	$ 0.03	$ 0.33	$ 0.27	$ 0.16