SPS Commerce (SPSC) 10-K 24 Feb 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2015	Feb. 09, 2016	Jun. 30, 2015
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Trading Symbol	SPSC
Entity Registrant Name	SPS COMMERCE INC
Entity Central Index Key	1,092,699
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		16,843,440
Entity Public Float			$ 1.1

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
CURRENT ASSETS
Cash and cash equivalents	$ 121,538	$ 130,795
Short-term marketable securities	7,517
Accounts receivable, net	17,615	15,422
Deferred costs	15,086	12,055
Deferred income taxes		76
Other current assets	5,030	3,846
Total current assets	166,786	162,194
PROPERTY AND EQUIPMENT, net	13,620	11,361
GOODWILL	33,848	34,854
INTANGIBLE ASSETS, net	15,081	18,851
MARKETABLE SECURITIES, non-current	14,950
OTHER ASSETS
Deferred costs, non-current	5,260	5,267
Deferred income taxes, non-current	11,149	11,035
Other non-current assets	1,037	213
Total assets	261,731	243,775
CURRENT LIABILITIES
Accounts payable	2,163	3,961
Accrued compensation	11,150	9,926
Accrued expenses	1,987	2,470
Deferred revenue	7,740	7,505
Deferred rent	1,194	698
Total current liabilities	24,234	24,560
OTHER LIABILITIES
Deferred revenue, non-current	11,005	10,653
Deferred rent, non-current	4,307	3,471
Total liabilities	$ 39,546	$ 38,684
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; 16,723,994 and 16,348,747 shares issued and outstanding, respectively	$ 17	$ 16
Additional paid-in capital	265,265	250,633
Accumulated deficit	(39,449)	(44,088)
Accumulated other comprehensive loss	(3,648)	(1,470)
Total stockholders' equity	222,185	205,091
Total liabilities and stockholders' equity	$ 261,731	$ 243,775

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
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	16,723,994	16,348,747
Common stock, shares outstanding	16,723,994	16,348,747

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Revenues	$ 158,518	$ 127,947	$ 104,391
Cost of revenues	50,043	39,991	31,781
Gross profit	108,475	87,956	72,610
Operating expenses
Sales and marketing	55,374	46,990	39,621
Research and development	17,954	13,494	10,870
General and administrative	24,817	20,233	17,189
Amortization of intangible assets	3,307	2,856	3,158
Total operating expenses	101,452	83,573	70,838
Income from operations	7,023	4,383	1,772
Other income (expense)
Interest income, net	197	187	112
Other expense, net	(145)	(458)	(147)
Total other income (expense), net	52	(271)	(35)
Income before income taxes	7,075	4,112	1,737
Income tax expense	(2,436)	(1,408)	(686)
Net income	$ 4,639	$ 2,704	$ 1,051
Net income per share
Basic	$ 0.28	$ 0.17	$ 0.07
Diluted	$ 0.27	$ 0.16	$ 0.07
Weighted average common shares used to compute net income per share
Basic	16,565	16,236	15,201
Diluted	17,032	16,814	15,931
Other comprehensive income (loss)
Foreign currency translation adjustments	$ (2,119)	$ (1,470)
Unrealized loss on investments	(59)
Comprehensive income	$ 2,461	$ 1,234	$ 1,051

Consolidated Statements of Stoc

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, 2012	$ 134,817	$ 15	$ 182,645	$ (47,843)
Beginning balance, shares at Dec. 31, 2012		14,812,759
Stock-based compensation	4,203		4,203
Exercise of stock options and issuance of restricted stock	3,735		3,735
Exercise of stock options and issuance of restricted stock, shares		497,248
Excess tax benefit of stock options exercised	156		156
Employee stock purchase plan	1,242		1,242
Employee stock purchase plan, shares		32,114
Stock offering, net of costs	47,569	$ 1	47,568
Stock offering, net of costs, shares		750,000
Net income	1,051			1,051
Ending balance at Dec. 31, 2013	192,773	$ 16	239,549	(46,792)
Ending 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

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities
Net income	$ 4,639	$ 2,704	$ 1,051
Reconciliation of net income to net cash provided by operating activities
Deferred income taxes	(38)	1,031	443
Depreciation and amortization of property and equipment	6,265	5,714	4,893
Amortization of intangible assets	3,307	2,856	3,158
Provision for doubtful accounts	1,271	717	479
Stock-based compensation	6,379	5,396	4,203
Changes in assets and liabilities, net of effects of acquisitions
Accounts receivable	(3,517)	(3,890)	(1,150)
Deferred costs	(3,023)	(4,590)	(2,184)
Other current assets	(2,037)	(719)	2,593
Other non-current assets			28
Accounts payable	(1,569)	1,271	(59)
Accrued compensation	1,295	1,568	1,943
Accrued expenses	(461)	1,365	(108)
Deferred revenue	587	2,440	1,309
Deferred rent	1,331	925	1,644
Net cash provided by operating activities	14,429	16,788	18,243
Cash flows from investing activities
Business acquisitions, net of cash acquired		(12,595)
Purchases of property and equipment	(8,757)	(7,582)	(5,701)
Purchases of marketable securities	(22,527)
Net cash used in investing activities	(31,284)	(20,177)	(5,701)
Cash flows from financing activities
Net proceeds from stock offerings			47,738
Stock offering costs			(169)
Net proceeds from exercise of options to purchase common stock	4,440	1,886	3,735
Excess tax benefit from exercise of options to purchase common stock	2,336	261	156
Net proceeds from employee stock purchase plan	1,478	1,338	1,242
Net cash provided by financing activities	8,254	3,485	52,702
Effect of foreign currency exchange rate changes	(656)	(595)
Net increase (decrease) in cash and cash equivalents	(9,257)	(499)	65,244
Cash and cash equivalents at beginning of period	130,795	131,294	66,050
Cash and cash equivalents at end of period	121,538	130,795	131,294
Supplemental disclosure of cash flow information
Cash paid for income taxes	$ 114	113	$ 55
Non-cash financing activities:
Common stock issued for business acquisitions		$ 2,203

General

General	12 Months Ended
	Dec. 31, 2015
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 integrations and 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 other customers manage and fulfill orders. 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 income (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/loss. 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 (loss). 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. 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. 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 December 31, 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 December 31. 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. 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 two and one-half 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. In 2015, we relied solely on the historical volatility of our common stock. Previously, in 2014, expected volatility was partially based on the historical volatilities of the publicly traded shares of a selected peer group, and partially based on the historical volatility of our common stock. This is because we did not have sufficient historical volatility data to rely solely 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 or expected employee exercise behavior. Advertising Costs Advertising costs are charged to expense as incurred. Advertising costs were approximately $47,000, $23,000 and $61,000 for the years ended December 31, 2015, 2014 and 2013, 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 FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) In November 2015, the FASB issued ASU No. 2015-17, Balance Sheet Classification of Deferred Taxes

Business Acquisitions

Business Acquisitions	12 Months Ended
	Dec. 31, 2015
Business Combinations [Abstract]
Business Acquisitions	NOTE B – Business Acquisitions 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 Estimated 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 statements 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 2013 Pro forma total revenue $ 132,818 $ 110,759 Pro forma net income 2,973 1,236 Pro forma net income per share Basic 0.18 0.08 Diluted 0.18 0.08 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.

Financial Instruments

Financial Instruments	12 Months Ended
	Dec. 31, 2015
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 (loss). 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 (loss). Cash equivalents and marketable securities, consisted of the following (in thousands): December 31, 2015 Amortized Unrealized Unrealized Fair Value Cash equivalents: Money market funds $ 79,717 $ — $ — $ 79,717 Marketable securities: Corporate bonds 10,042 — (34 ) 10,008 Commercial paper 2,499 1 — 2,500 U.S. treasury securities 7,489 — (27 ) 7,462 U.S. agency obligations 2,497 1 — 2,498 $ 102,244 $ 2 $ (61 ) $ 102,185 Due within one year $ 87,235 Due within two years 14,950 Total $ 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, 2015. We expect to receive the full principal and interest on all of these cash equivalents and marketable securities. There were no unrealized gains or losses for our money market funds as of December 31, 2014. 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, 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 Assets at December 31, 2014: Cash and cash equivalents: Money market funds $ 66,052 $ — $ — $ 66,052 $ 66,052 $ — $ — $ 66,052

Allowance for Doubtful Accounts

Allowance for Doubtful Accounts	12 Months Ended
	Dec. 31, 2015
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): 2015 2014 2013 Balances, January 1 $ 279 $ 237 $ 227 Provision for doubtful accounts 1,271 717 479 Write-offs (1,198 ) (750 ) (504 ) Recoveries 94 75 35 Balances, December 31 $ 446 $ 279 $ 237

Property and Equipment, net

Property and Equipment, net	12 Months Ended
	Dec. 31, 2015
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, 2015 2014 Computer equipment and software $ 27,725 $ 22,766 Office equipment and furniture 5,793 5,015 Leasehold improvements 5,530 4,039 39,048 31,820 Less: accumulated depreciation and amortization (25,428 ) (20,459 ) $ 13,620 $ 11,361 At December 31, 2015 and 2014, property and equipment, net included approximately $709,000 and $680,000, respectively, of assets held at subsidiary and office locations outside of the United States of America.

Goodwill and Intangible Assets,

Goodwill and Intangible Assets, net	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets, net	NOTE F – Goodwill and Intangible Assets, net The change in the goodwill balance for the year ended December 31, 2015 was due to the effect of foreign currency translation for the goodwill related to Leadtec that is based in Australian dollars. The change in goodwill for the year ended December 31, 2014 was due to the $10.0 million of goodwill from the acquisition of Leadtec (see Note B), partially offset by the effect of foreign currency translation. Intangible assets, net included the following (in thousands): December 31, 2015 2014 Carrying Accumulated Net Carrying Accumulated Net Subscriber relationships $ 26,337 $ (11,856 ) $ 14,481 $ 26,724 $ (8,992 ) $ 17,732 Non-competition agreements 1,834 (1,653 ) 181 1,849 (1,581 ) 268 Technology and other 819 (400 ) 419 922 (71 ) 851 $ 28,990 $ (13,909 ) $ 15,081 $ 29,495 $ (10,644 ) $ 18,851 Amortization expense for the year ended December 31, 2013 included $290,000 for the impairment of a certain non-competition agreement. At December 31, 2015, future amortization expense for intangible assets was as follows (in thousands): 2016 $ 3,298 2017 3,027 2018 2,448 2019 2,158 2020 2,136 Thereafter 2,014 $ 15,081

Line of Credit

Line of Credit	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Line of Credit	NOTE G – Line of Credit In the fourth quarter of 2015, we closed the revolving credit agreement with JPMorgan Chase Bank, N.A. which provided for a $20 million revolving credit facility. There were no borrowings under the revolving credit agreement in 2015 or 2014 and we were in compliance with all covenants under the revolving credit agreement while the credit line was available.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	NOTE H – 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 $4.6 million, $3.7 million and $2.8 million for the years ended December 31, 2015, 2014 and 2013, respectively. On September 1, 2015, we executed a new lease agreement at our New Jersey office location which commences 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 5 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, 2015, our future minimum payments under operating leases were as follows (in thousands): 2016 $ 3,306 2017 2,976 2018 2,907 2019 3,003 2020 1,447 Thereafter 1,861 $ 15,500 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 significant adverse effect on our financial position, results of operations or cash flows.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Stockholders' Equity	NOTE I – Stockholders’ Equity Common Stock Issued 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. On November 25, 2013, we completed a public stock offering where we issued and sold 750,000 shares of our common stock at a price to the public of $67.00 per share. We received net proceeds of approximately $47.6 million from this offering after payment of approximately $2.7 million of underwriting discounts and commissions and legal, accounting and other fees incurred in connection with the offering.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	NOTE J – 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 January 2015, 980,924 additional shares were reserved for future issuance under our 2010 Equity Incentive Plan. At December 31, 2015, there were approximately 3.3 million shares available for grant under approved equity compensation plans. We recorded stock-based compensation expense of $6.4 million, $5.4 million and $4.2 million for the years ended December 31, 2015, 2014 and 2013, respectively. This expense was allocated as follows (in thousands): Year Ended December 31, 2015 2014 2013 Cost of revenues $ 989 $ 614 $ 475 Operating expenses Sales and marketing 1,978 1,933 1,481 Research and development 640 444 266 General and administrative 2,772 2,405 1,981 Total stock-based compensation expense $ 6,379 $ 5,396 $ 4,203 As of December 31, 2015, there was approximately $11.3 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 Outstanding at January 1, 2013 1,370,141 $ 12.41 Granted 225,439 40.64 Exercised (469,225 ) 7.96 Forfeited (29,132 ) 30.93 Outstanding at December 31, 2013 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 Of the total outstanding options at December 31, 2015, 640,096 were exercisable with a weighted average exercise price of $27.25 per share. The total outstanding options had a weighted average remaining contractual life of 4.7 years. The fair value of options that vested during the years ended December 31, 2015, 2014 and 2013 was $3.1 million, $2.9 million and $2.6 million, respectively. The intrinsic value of options exercised during the years ended December 31, 2015, 2014 and 2013 was $16.8 million, $7.4 million and $20.7 million, respectively. The intrinsic value of outstanding options at December 31, 2015, 2014 and 2013 was $30.5 million, $33.8 million and $50.1 million, respectively. The weighted-average fair values per share of options granted during 2015, 2014 and 2013 were $23.09, $24.36 and $14.60, 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, 2015 2014 2013 Volatility 39 % 42 % 41 % Dividend yield — — — Life (in years) 4.52 4.17 4.75 Risk-free interest rate 1.36 % 1.44 % 0.86 % Prior to becoming a public entity in 2010, historical volatility was not available for our common stock. As a result, we did not have sufficient data to rely solely on the historical volatility of our common stock. Therefore, we estimated volatility based partially on the historical volatilities of the publicly traded shares of a selected peer group, and partially on the historical volatility of our common stock, which collectively provided a reasonable basis for estimating volatility. Beginning in 2015, we relied solely 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 or expected 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 Weighted Average Outstanding at January 1, 2013 68,241 $ 26.35 Granted 59,695 40.06 Vested and common stock issued (17,060 ) 26.09 Forfeited (8,232 ) 33.85 Outstanding at December 31, 2013 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 The number of restricted stock units outstanding at December 31, 2015 included 31,987 units that have vested but for which 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 Outstanding at January 1, 2013 5,275 $ 27.55 Restricted common stock issued 5,688 48.66 Restrictions lapsed (9,541 ) 36.99 Forfeited — — Outstanding at December 31, 2013 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 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 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 offering periods in 2013, we withheld approximately $1.2 million from employees participating in the plan and we purchased 32,114 shares on their behalf. For the years ended December 31, 2015, 2014 and 2013, we recorded approximately $408,000, $473,000 and $402,000 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, 2015 2014 2013 Volatility 30 % 45 % 46 % Dividend yield — — — Life (in years) 0.50 0.50 0.50 Risk-free interest rate 0.12 % 0.08 % 0.10 %

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	NOTE K – Income Taxes The provision for income taxes was as follows (in thousands): Year Ended December 31, 2015 2014 2013 Current Federal $ 2,066 $ 43 $ — State 289 254 192 Foreign 119 80 51 Deferred Federal 103 1,183 450 State (141 ) (152 ) (7 ) $ 2,436 $ 1,408 $ 686 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, 2015 2014 2013 Expected federal income tax at statutory rate $ 2,404 $ 1,398 $ 593 State income taxes, net of federal tax effect 246 124 78 Tax impact of foreign activity 39 37 44 Permanent book/tax differences 67 173 106 Change in valuation allowance (27 ) (88 ) 17 Change in state deferred rate (118 ) (9 ) 53 Prior year true up 46 (43 ) 4 Research and development credit (200 ) (178 ) (202 ) Other (21 ) (6 ) (7 ) Total provision for income taxes $ 2,436 $ 1,408 $ 686 The significant components of our deferred tax assets (liabilities) were as follows (in thousands): December 31, 2015 2014 Deferred tax assets Net operating loss and credit carryforwards $ 4,687 $ 5,038 Deferred operations 1,443 1,823 Stock-based compensation expense 3,284 2,721 Depreciation and amortization 1,179 1,567 Accounts receivable allowances 252 172 Accrued expenses 1,137 940 Other 234 40 Gross deferred tax asset 12,216 12,301 Less: valuation allowance (928 ) (1,149 ) Total net deferred tax asset 11,288 11,152 Deferred tax liability Foreign operations (139 ) (41 ) Total deferred tax liability (139 ) (41 ) Net deferred tax assets $ 11,149 $ 11,111 As of December 31, 2015, we had net operating loss carryforwards of $82.9 million for U.S. federal tax purposes. We also had $31.4 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 2016 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, 2015 included $57.3 million and $16.7 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, 2015 we had federal research and development credit carryforwards, net of Section 383 limitations, of $709,000, which, if not utilized, will begin to expire in 2030. We had state research and development credit carryforwards of $297,000, which, if not utilized, will begin to expire in 2025. As of December 31, 2015, we had a valuation allowance against our deferred tax assets of $928,000. The valuation allowance is established for various 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, 2015, 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

Net Income Per Share	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Net Income Per Share	NOTE L – 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, 2015 2014 2013 Numerator Net income $ 4,639 $ 2,704 $ 1,051 Denominator Weighted average common shares outstanding, basic 16,565 16,236 15,201 Options to purchase common stock 437 535 676 Restricted stock units 27 42 51 Employee stock purchase plan 3 1 3 Weighted average common shares outstanding, diluted 17,032 16,814 15,931 Net income per share Basic $ 0.28 $ 0.17 $ 0.07 Diluted $ 0.27 $ 0.16 $ 0.07 For the years ended December 31, 2015, 2014, and 2013, the effect of approximately 4,000, 126,000, and 1,000 outstanding potential common shares, respectively, were excluded from the calculation of diluted net income per share because they were anti-dilutive.

Retirement Savings Plan

Retirement Savings Plan	12 Months Ended
	Dec. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Retirement Savings Plan	NOTE M – 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. The company will match 25% of the employee’s contribution up to the first 6% of pre-tax annual compensation. Additionally, the company makes statutory contributions to retirement plans as required by local foreign government regulations. Our contributions to the plans, which vest immediately, were $1.1 million, $733,000 and $522,000 for the years ended December 31, 2015, 2014 and 2013, respectively.

Selected Quarterly Financial Da

Selected Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2015
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 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 For the Three Months Ended 2014 Mar 31 Jun 30 Sep 30 Dec 31 Revenues $ 28,939 $ 31,100 $ 32,506 $ 35,402 Gross profit 19,684 21,473 22,536 24,263 Income from operations 598 1,014 1,354 1,417 Net income 373 639 838 854 Diluted earnings per share $ 0.02 $ 0.04 $ 0.05 $ 0.05 Quarterly earnings per share amounts above may not equal the sum of the annual earnings per share amounts due to rounding

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	NOTE O – Subsequent Events On January 5, 2016, our wholly owned subsidiary SPS Commerce Canada, Ltd. entered into a purchase agreement with the shareholders of Toolbox Solutions, Inc. (“Toolbox) to acquire all shares of Toolbox. Toolbox provides point-of-sale analytics and category management services to retailers and consumer packaged goods suppliers in North America. This acquisition expands our retail network along with our geographical presence and strengthens our analytics offerings. We paid $18.4 million in cash and $4.5 million in stock, or 64,891 shares of common stock, to the shareholders of Toolbox. This amount includes $1.1 million of stock, or 16,222 shares of common stock, that is subject to an earn-out and has not yet been issued. As of filing, we have not yet finalized our purchase accounting for this transaction.

General (Policies)

General (Policies)	12 Months Ended
	Dec. 31, 2015
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 integrations and 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 other customers manage and fulfill orders. 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 income (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/loss. 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 (loss).
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.
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. 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 December 31, 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 December 31. 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.
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 two and one-half 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. In 2015, we relied solely on the historical volatility of our common stock. Previously, in 2014, expected volatility was partially based on the historical volatilities of the publicly traded shares of a selected peer group, and partially based on the historical volatility of our common stock. This is because we did not have sufficient historical volatility data to rely solely 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 or expected employee exercise behavior.
Advertising Costs	Advertising Costs Advertising costs are charged to expense as incurred. Advertising costs were approximately $47,000, $23,000 and $61,000 for the years ended December 31, 2015, 2014 and 2013, 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 FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) In November 2015, the FASB issued ASU No. 2015-17, Balance Sheet Classification of Deferred Taxes

Business Acquisitions (Tables)

Business Acquisitions (Tables) - Leadtec [Member]	12 Months Ended
	Dec. 31, 2015
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 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 Estimated Subscriber relationships $ 3,778 9 Non-competition agreements 148 5 Technology and other 965 2.5 Total $ 4,891
Unaudited Pro Forma Financial Information	Year Ended December 31, (in thousands, except per share data) 2014 2013 Pro forma total revenue $ 132,818 $ 110,759 Pro forma net income 2,973 1,236 Pro forma net income per share Basic 0.18 0.08 Diluted 0.18 0.08

Financial Instruments (Tables)

Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2015
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, 2015 Amortized Unrealized Unrealized Fair Value Cash equivalents: Money market funds $ 79,717 $ — $ — $ 79,717 Marketable securities: Corporate bonds 10,042 — (34 ) 10,008 Commercial paper 2,499 1 — 2,500 U.S. treasury securities 7,489 — (27 ) 7,462 U.S. agency obligations 2,497 1 — 2,498 $ 102,244 $ 2 $ (61 ) $ 102,185 Due within one year $ 87,235 Due within two years 14,950 Total $ 102,185
Summary of Financial Assets Measured at Fair Value on a Recurring Basis	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, 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 Assets at December 31, 2014: Cash and cash equivalents: Money market funds $ 66,052 $ — $ — $ 66,052 $ 66,052 $ — $ — $ 66,052

Allowance for Doubtful Accoun25

Allowance for Doubtful Accounts (Tables)	12 Months Ended
	Dec. 31, 2015
Text Block [Abstract]
Schedule of Allowance for Doubtful Activity Including in Accounts Receivable Net	The allowance for doubtful accounts activity, included in accounts receivable, net, was as follows (in thousands): 2015 2014 2013 Balances, January 1 $ 279 $ 237 $ 227 Provision for doubtful accounts 1,271 717 479 Write-offs (1,198 ) (750 ) (504 ) Recoveries 94 75 35 Balances, December 31 $ 446 $ 279 $ 237

Property and Equipment, net (Ta

Property and Equipment, net (Tables)	12 Months Ended
	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Schedule of Property and Equipment, Net	Property and equipment, net included the following (in thousands): December 31, 2015 2014 Computer equipment and software $ 27,725 $ 22,766 Office equipment and furniture 5,793 5,015 Leasehold improvements 5,530 4,039 39,048 31,820 Less: accumulated depreciation and amortization (25,428 ) (20,459 ) $ 13,620 $ 11,361

Goodwill and Intangible Asset27

Goodwill and Intangible Assets, net (Tables)	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	Intangible assets, net included the following (in thousands): December 31, 2015 2014 Carrying Accumulated Net Carrying Accumulated Net Subscriber relationships $ 26,337 $ (11,856 ) $ 14,481 $ 26,724 $ (8,992 ) $ 17,732 Non-competition agreements 1,834 (1,653 ) 181 1,849 (1,581 ) 268 Technology and other 819 (400 ) 419 922 (71 ) 851 $ 28,990 $ (13,909 ) $ 15,081 $ 29,495 $ (10,644 ) $ 18,851
Future Amortization Expense for Intangible Assets	At December 31, 2015, future amortization expense for intangible assets was as follows (in thousands): 2016 $ 3,298 2017 3,027 2018 2,448 2019 2,158 2020 2,136 Thereafter 2,014 $ 15,081

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Future Minimum Payments Under Operating Leases	At December 31, 2015, our future minimum payments under operating leases were as follows (in thousands): 2016 $ 3,306 2017 2,976 2018 2,907 2019 3,003 2020 1,447 Thereafter 1,861 $ 15,500

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2015
Stock-Based Compensation Expense	This expense was allocated as follows (in thousands): Year Ended December 31, 2015 2014 2013 Cost of revenues $ 989 $ 614 $ 475 Operating expenses Sales and marketing 1,978 1,933 1,481 Research and development 640 444 266 General and administrative 2,772 2,405 1,981 Total stock-based compensation expense $ 6,379 $ 5,396 $ 4,203
Stock Option Activity	Our stock option activity was as follows: Options (#) Weighted Average Outstanding at January 1, 2013 1,370,141 $ 12.41 Granted 225,439 40.64 Exercised (469,225 ) 7.96 Forfeited (29,132 ) 30.93 Outstanding at December 31, 2013 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
Weighted Average Fair Value Per Share of Options Granted, Assumptions	The weighted-average fair values per share of options granted during 2015, 2014 and 2013 were $23.09, $24.36 and $14.60, 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, 2015 2014 2013 Volatility 39 % 42 % 41 % Dividend yield — — — Life (in years) 4.52 4.17 4.75 Risk-free interest rate 1.36 % 1.44 % 0.86 %
Weighted Average Fair Value Per Share, Employee Stock Purchase Plan, 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, 2015 2014 2013 Volatility 30 % 45 % 46 % Dividend yield — — — Life (in years) 0.50 0.50 0.50 Risk-free interest rate 0.12 % 0.08 % 0.10 %
Restricted Stock Units [Member]
Restricted Stock Units and Restricted Stock Awards	Our restricted stock units activity was as follows: Restricted Stock Weighted Average Outstanding at January 1, 2013 68,241 $ 26.35 Granted 59,695 40.06 Vested and common stock issued (17,060 ) 26.09 Forfeited (8,232 ) 33.85 Outstanding at December 31, 2013 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
Restricted Stock Award [Member]
Restricted Stock Units and Restricted Stock Awards	Our restricted stock awards activity was as follows: Restricted Stock Awards (#) Weighted Average Outstanding at January 1, 2013 5,275 $ 27.55 Restricted common stock issued 5,688 48.66 Restrictions lapsed (9,541 ) 36.99 Forfeited — — Outstanding at December 31, 2013 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

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Schedule of Provision for Income Taxes	The provision for income taxes was as follows (in thousands): Year Ended December 31, 2015 2014 2013 Current Federal $ 2,066 $ 43 $ — State 289 254 192 Foreign 119 80 51 Deferred Federal 103 1,183 450 State (141 ) (152 ) (7 ) $ 2,436 $ 1,408 $ 686
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, 2015 2014 2013 Expected federal income tax at statutory rate $ 2,404 $ 1,398 $ 593 State income taxes, net of federal tax effect 246 124 78 Tax impact of foreign activity 39 37 44 Permanent book/tax differences 67 173 106 Change in valuation allowance (27 ) (88 ) 17 Change in state deferred rate (118 ) (9 ) 53 Prior year true up 46 (43 ) 4 Research and development credit (200 ) (178 ) (202 ) Other (21 ) (6 ) (7 ) Total provision for income taxes $ 2,436 $ 1,408 $ 686
Significant Components of Deferred Tax Assets (Liabilities)	The significant components of our deferred tax assets (liabilities) were as follows (in thousands): December 31, 2015 2014 Deferred tax assets Net operating loss and credit carryforwards $ 4,687 $ 5,038 Deferred operations 1,443 1,823 Stock-based compensation expense 3,284 2,721 Depreciation and amortization 1,179 1,567 Accounts receivable allowances 252 172 Accrued expenses 1,137 940 Other 234 40 Gross deferred tax asset 12,216 12,301 Less: valuation allowance (928 ) (1,149 ) Total net deferred tax asset 11,288 11,152 Deferred tax liability Foreign operations (139 ) (41 ) Total deferred tax liability (139 ) (41 ) Net deferred tax assets $ 11,149 $ 11,111

Net Income Per Share (Tables)

Net Income Per Share (Tables)	12 Months Ended
	Dec. 31, 2015
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, 2015 2014 2013 Numerator Net income $ 4,639 $ 2,704 $ 1,051 Denominator Weighted average common shares outstanding, basic 16,565 16,236 15,201 Options to purchase common stock 437 535 676 Restricted stock units 27 42 51 Employee stock purchase plan 3 1 3 Weighted average common shares outstanding, diluted 17,032 16,814 15,931 Net income per share Basic $ 0.28 $ 0.17 $ 0.07 Diluted $ 0.27 $ 0.16 $ 0.07

Selected Quarterly Financial 32

Selected Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2015
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 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 For the Three Months Ended 2014 Mar 31 Jun 30 Sep 30 Dec 31 Revenues $ 28,939 $ 31,100 $ 32,506 $ 35,402 Gross profit 19,684 21,473 22,536 24,263 Income from operations 598 1,014 1,354 1,417 Net income 373 639 838 854 Diluted earnings per share $ 0.02 $ 0.04 $ 0.05 $ 0.05

General - Additional Informatio

General - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2015USD ($)Segment	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Schedule Of Accounting Policies [Line Items]
Number of reportable segments | Segment	1
Expected life of customer relationship period	2 years
Advertising costs | $	$ 47,000	$ 23,000	$ 61,000
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]
Schedule Of Accounting Policies [Line Items]
Estimated useful lives of intangible assets	2 years 6 months

Business Acquisitions - Additio

Business Acquisitions - Additional Information (Detail) - USD ($)	Oct. 12, 2014	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Oct. 10, 2014
Business Acquisition [Line Items]
Amortization expense for purchased intangible assets			$ 3,307,000	$ 2,856,000	$ 3,158,000
Leadtec [Member]
Business Acquisition [Line Items]
Assets acquired in cash	$ 12,600,000			12,595,000
Number of shares of common stock issued for acquisition	43,595
Fair value of the shares issued						$ 2,200,000
Amortization expense for purchased intangible assets		$ 168,000	$ 733,000
Acquisition-related cost included in consolidated statements				690,000
Acquisition related one-time Australian stamp duty tax				$ 338,000
Revenues from acquisition		1,200,000
Operating loss from acquisition		$ (280,000)

Business Acquisitions - Busines

Business Acquisitions - Business Purchase Price (Detail) - Leadtec [Member] - USD ($) $ in Thousands	Oct. 12, 2014	Dec. 31, 2014
Business Acquisition [Line Items]
Cash	$ 12,600	$ 12,595
SPS Commerce, Inc. common stock		2,203
Total purchase price		$ 14,798

Business Acquisitions - Estimat

Business Acquisitions - Estimated Fair Values of the Assets Acquired and Liabilities Assumed at the Acquisition Date (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
GOODWILL	$ 33,848	$ 34,854
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 - Estim37

Business Acquisitions - Estimated Fair Value of Purchased Intangible Assets and Estimated Useful Lives (Detail) - Leadtec [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2014USD ($)
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 4,891
Subscriber Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 3,778
Estimated Life (in years)	9 years
Non-competition Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 148
Estimated Life (in years)	5 years
Technology and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated Fair Value	$ 965
Estimated Life (in years)	2 years 6 months

Business Acquisitions - Unaudit

Business Acquisitions - Unaudited Pro Forma Financial Information (Detail) - Leadtec [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Pro forma total revenue	$ 132,818	$ 110,759
Pro forma net income	$ 2,973	$ 1,236
Pro forma net income per share, Basic	$ 0.18	$ 0.08
Pro forma net income per share, Diluted	$ 0.18	$ 0.08

Financial Instruments - Summary

Financial Instruments - Summary of Investment in Cash Equivalents and Marketable Securities (Detail) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 102,244,000
Due within one year	87,235,000
Unrealized Gains	2,000
Due within two years	14,950,000
Unrealized Losses	(61,000)
Fair Value	102,185,000
Money Market Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	79,717,000
Unrealized Gains		$ 0
Unrealized Losses		$ 0
Fair Value	79,717,000
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	10,042,000
Unrealized Losses	(34,000)
Fair Value	10,008,000
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,499,000
Unrealized Gains	1,000
Fair Value	2,500,000
U.S. Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	7,489,000
Unrealized Losses	(27,000)
Fair Value	7,462,000
U.S. Agency Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,497,000
Unrealized Gains	1,000
Fair Value	$ 2,498,000

Financial Instruments - Additio

Financial Instruments - Additional Information (Detail) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Cash and Cash Equivalents [Line Items]
Unrealized Gains	$ 2,000
Unrealized Losses	$ 61,000
Money Market Funds [Member]
Cash and Cash Equivalents [Line Items]
Unrealized Gains		$ 0
Unrealized Losses		$ 0

Financial Instruments - Summa41

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, 2015	Dec. 31, 2014
Cash and Cash Equivalents [Line Items]
Assets fair value	$ 102,185	$ 66,052
Money Market Funds [Member]
Cash and Cash Equivalents [Line Items]
Assets fair value	79,717	66,052
Corporate Bonds [Member]
Cash and Cash Equivalents [Line Items]
Assets fair value	10,008
Commercial Paper [Member]
Cash and Cash Equivalents [Line Items]
Assets fair value	2,500
U.S. Treasury Securities [Member]
Cash and Cash Equivalents [Line Items]
Assets fair value	7,462
U.S. Agency Obligations [Member]
Cash and Cash Equivalents [Line Items]
Assets fair value	2,498
Level 1 [Member]
Cash and Cash Equivalents [Line Items]
Assets fair value	79,717	66,052
Level 1 [Member] | Money Market Funds [Member]
Cash and Cash Equivalents [Line Items]
Assets fair value	79,717	$ 66,052
Level 2 [Member]
Cash and Cash Equivalents [Line Items]
Assets fair value	22,468
Level 2 [Member] | Corporate Bonds [Member]
Cash and Cash Equivalents [Line Items]
Assets fair value	10,008
Level 2 [Member] | Commercial Paper [Member]
Cash and Cash Equivalents [Line Items]
Assets fair value	2,500
Level 2 [Member] | U.S. Treasury Securities [Member]
Cash and Cash Equivalents [Line Items]
Assets fair value	7,462
Level 2 [Member] | U.S. Agency Obligations [Member]
Cash and Cash Equivalents [Line Items]
Assets fair value	$ 2,498

Allowance for Doubtful Accoun42

Allowance for Doubtful Accounts - Schedule of Allowance for Doubtful Activity Included in Accounts Receivable Net (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Receivables [Abstract]
Beginning Balance	$ 279	$ 237	$ 227
Provision for doubtful accounts	1,271	717	479
Write-offs	(1,198)	(750)	(504)
Recoveries	94	75	35
Ending Balance	$ 446	$ 279	$ 237

Property and Equipment, net - S

Property and Equipment, net - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 39,048	$ 31,820
Less: accumulated depreciation and amortization	(25,428)	(20,459)
Net, Total	13,620	11,361
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	27,725	22,766
Office Equipment and Furniture [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	5,793	5,015
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 5,530	$ 4,039

Property and Equipment, net - A

Property and Equipment, net - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
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	$ 709,000	$ 680,000

Goodwill and Intangible Asset45

Goodwill and Intangible Assets, net - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]
Change in goodwill from acquisitions during the period	$ 10,000,000
Impairment of non-competition agreements		$ 290,000

Goodwill and Intangible Asset46

Goodwill and Intangible Assets, net - Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Carrying Amount	$ 28,990	$ 29,495
Accumulated Amortization	(13,909)	(10,644)
Net	15,081	18,851
Subscriber Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Carrying Amount	26,337	26,724
Accumulated Amortization	(11,856)	(8,992)
Net	14,481	17,732
Non-competition Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Carrying Amount	1,834	1,849
Accumulated Amortization	(1,653)	(1,581)
Net	181	268
Technology and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Carrying Amount	819	922
Accumulated Amortization	(400)	(71)
Net	$ 419	$ 851

Goodwill and Intangible Asset47

Goodwill and Intangible Assets, net - Future Amortization Expense for Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
2,016	$ 3,298
2,017	3,027
2,018	2,448
2,019	2,158
2,020	2,136
Thereafter	2,014
Net	$ 15,081	$ 18,851

Line of Credit - Additional Inf

Line of Credit - Additional Information (Detail) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Line of Credit Facility [Line Items]
Revolving credit facility, amount	$ 20,000,000
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Borrowings outstanding revolving credit agreement	$ 0	$ 0

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) $ in Millions	Sep. 01, 2015OptionPlan	Feb. 14, 2012OptionPlan	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Commitments and Contingencies Disclosure [Abstract]
Rent expense charged to operations | $			$ 4.6	$ 3.7	$ 2.8
Lease agreement expires, date	Jun. 30, 2023	Apr. 30, 2020
Number of options to extend term of the lease | OptionPlan	1	2
Options to extend the term of the lease, number of years	5 years	3 years

Commitments and Contingencies50

Commitments and Contingencies - Future Minimum Payments Under Operating Leases (Detail) $ in Thousands	Dec. 31, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,016	$ 3,306
2,017	2,976
2,018	2,907
2,019	3,003
2,020	1,447
Thereafter	1,861
Operating leases, total	$ 15,500

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Oct. 12, 2014	Nov. 25, 2013	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Oct. 10, 2014
Schedule Of Stockholders Equity [Line Items]
Common stock issued and sold		750,000		16,723,994	16,348,747
Issue price of shares		$ 67
Net proceeds from issue of shares		$ 47,600	$ 47,738
Underwriting discounts and commissions and legal, accounting and other fees		$ 2,700	$ 169
Leadtec [Member]
Schedule Of Stockholders Equity [Line Items]
Common stock shares, issued	43,595
Fair value of the shares issued						$ 2,200

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail)	1 Months Ended	12 Months Ended
	Jan. 31, 2015shares	Dec. 31, 2015USD ($)OfferingPeriods$ / sharesshares	Dec. 31, 2014USD ($)$ / sharesshares	Dec. 31, 2013USD ($)$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant | shares		3,300,000
Stock-based compensation expense		$ 6,379,000	$ 5,396,000	$ 4,203,000
Unrecognized stock-based compensation expense		$ 11,300,000
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		640,096
Weighted average exercise price | $ / shares		$ 27.25
Weighted average remaining contractual life		4 years 8 months 12 days
Fair value of options vested		$ 3,100,000	2,900,000	2,600,000
Intrinsic value of options exercised		16,800,000	7,400,000	20,700,000
Intrinsic value of options outstanding		$ 30,500,000	$ 33,800,000	$ 50,100,000
Weighted average fair value per share of options granted | $ / shares		$ 23.09	$ 24.36	$ 14.60
Number of RSU's vested and not issued during the period | shares		31,987
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		$ 408,000	$ 473,000	$ 402,000
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	980,924
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee stock purchase plan, employees contribution		$ 1,500,000	$ 1,300,000	$ 1,200,000
Employee stock purchase plan, shares purchased | shares		28,362	26,353	32,114
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 - Stoc

Stock-Based Compensation - Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 6,379	$ 5,396	$ 4,203
Cost of Revenues [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	989	614	475
Sales and Marketing [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	1,978	1,933	1,481
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	640	444	266
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 2,772	$ 2,405	$ 1,981

Stock-Based Compensation - St54

Stock-Based Compensation - Stock Option Activity (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Options Outstanding, Beginning balance	1,085,463	1,097,223	1,370,141
Options, Granted	181,487	153,770	225,439
Options, Exercised	(305,106)	(153,196)	(469,225)
Options, Forfeited	(18,741)	(12,334)	(29,132)
Options Outstanding, Ending balance	943,103	1,085,463	1,097,223
Weighted Average Exercise Price, Outstanding, Beginning Balance	$ 26.53	$ 19.62	$ 12.41
Weighted Average Exercise Price, Granted	67.50	62.86	40.64
Weighted Average Exercise Price, Exercised	14.55	12.27	7.96
Weighted Average Exercise Price, Forfeited	45.82	41.38	30.93
Weighted Average Exercise Price, Outstanding, Ending Balance	$ 37.91	$ 26.53	$ 19.62

Stock-Based Compensation - Weig

Stock-Based Compensation - Weighted Average Fair Value Per Share of Options Granted, Assumptions (Detail) - Stock Options [Member]	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility	39.00%	42.00%	41.00%
Dividend yield	0.00%	0.00%	0.00%
Life (in years)	4 years 6 months 7 days	4 years 2 months 1 day	4 years 9 months
Risk-free interest rate	1.36%	1.44%	0.86%

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Units (Detail) - Restricted Stock Units [Member] - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, Outstanding, Beginning Balance	115,133	102,644	68,241
Granted, stock units	68,159	42,001	59,695
Vested, stock units	(37,669)	(28,367)	(17,060)
Forfeited, stock units	(5,058)	(1,145)	(8,232)
Stock awards, Outstanding, Ending Balance	140,565	115,133	102,644
Weighted average grant date fair value, Outstanding, Beginning Balance	$ 45.25	$ 33.77	$ 26.35
Granted, Weighted Average Grant Date Fair Value	67.50	64.89	40.06
Vested, Weighted Average Grant Date Fair Value	40.91	32.92	26.09
Forfeited, Weighted Average Grant Date Fair Value	54.28	35.42	33.85
Weighted average grant date fair value, Outstanding, Ending Balance	$ 56.88	$ 45.25	$ 33.77

Stock-Based Compensation - Re57

Stock-Based Compensation - Restricted Stock Awards (Detail) - Restricted Stock Award [Member] - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards, Outstanding, Beginning Balance	1,338	1,422	5,275
Restricted common stock issued, stock awards	4,110	5,352	5,688
Restrictions lapsed, stock awards	(4,416)	(5,199)	(9,541)
Forfeited, stock awards		(237)
Stock awards, Outstanding, Ending Balance	1,032	1,338	1,422
Weighted average grant date fair value, Outstanding, Beginning Balance	$ 51.74	$ 48.66	$ 27.55
Restricted common stock issued, Weighted Average Grant Date Fair Value	67.37	51.74	48.66
Restrictions lapsed, Weighted Average Grant Date Fair Value	62.63	51.04	36.99
Forfeited, Weighted Average Grant Date Fair Value		48.66
Weighted average grant date fair value, Outstanding, Ending Balance	$ 67.39	$ 51.74	$ 48.66

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value Estimation of Common Stock Using Black-Scholes Option Pricing Model, Assumptions (Detail) - Employee Stock Purchase Plan [Member]	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility	30.00%	45.00%	46.00%
Dividend yield	0.00%	0.00%	0.00%
Life (in years)	6 months	6 months	6 months
Risk-free interest rate	0.12%	0.08%	0.10%

Income Taxes - Schedule of Prov

Income Taxes - Schedule of Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current
Federal	$ 2,066	$ 43
State	289	254	$ 192
Foreign	119	80	51
Deferred
Federal	103	1,183	450
State	(141)	(152)	(7)
Total provision (benefit) for income taxes	$ 2,436	$ 1,408	$ 686

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Provision for Income Taxes to Statutory Federal Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Expected federal income tax at statutory rate	$ 2,404	$ 1,398	$ 593
State income taxes, net of federal tax effect	246	124	78
Tax impact of foreign activity	39	37	44
Permanent book/tax differences	67	173	106
Change in valuation allowance	(27)	(88)	17
Change in state deferred rate	(118)	(9)	53
Prior year true up	46	(43)	4
Research and development credit	(200)	(178)	(202)
Other	(21)	(6)	(7)
Total provision (benefit) for income taxes	$ 2,436	$ 1,408	$ 686

Income Taxes - Significant Comp

Income Taxes - Significant Components of Deferred Tax Assets (Liabilities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets
Net operating loss and credit carryforwards	$ 4,687	$ 5,038
Deferred operations	1,443	1,823
Stock-based compensation expense	3,284	2,721
Depreciation and amortization	1,179	1,567
Accounts receivable allowances	252	172
Accrued expenses	1,137	940
Other	234	40
Gross deferred tax asset	12,216	12,301
Less: valuation allowance	(928)	(1,149)
Total net deferred tax asset	11,288	11,152
Deferred tax liability
Foreign operations	(139)	(41)
Total deferred tax liability	(139)	(41)
Net deferred tax assets	$ 11,149	$ 11,111

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Income Tax Expense Benefit [Line Items]
Net operating losses	$ 4,687,000	$ 5,038,000
Valuation allowance against our deferred tax assets	928,000
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	82,900,000
Unused federal losses that will expire	17,600,000
Maximum annual limitation of federal net operating losses	990,000
Net operating losses	57,300,000
Domestic Tax Authority [Member] | Research and Development [Member]
Income Tax Expense Benefit [Line Items]
Research and development credit carryforwards	$ 709,000
Research and development credit expire date	2,030
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	$ 31,400,000
Net operating losses	16,700,000
State and Local Jurisdiction [Member] | Research and Development [Member]
Income Tax Expense Benefit [Line Items]
Research and development credit carryforwards	$ 297,000
Research and development credit expire date	2,025
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 2016 and 2036 if not utilized

Net Income Per Share - Componen

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, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Numerator
Net income	$ 2,132	$ 1,270	$ 651	$ 586	$ 854	$ 838	$ 639	$ 373	$ 4,639	$ 2,704	$ 1,051
Denominator
Weighted average common shares outstanding, basic									16,565	16,236	15,201
Options to purchase common stock									437	535	676
Restricted stock units									27	42	51
Employee stock purchase plan									3	1	3
Weighted average common shares outstanding, diluted									17,032	16,814	15,931
Net income per share
Basic									$ 0.28	$ 0.17	$ 0.07
Diluted	$ 0.12	$ 0.07	$ 0.04	$ 0.03	$ 0.05	$ 0.05	$ 0.04	$ 0.02	$ 0.27	$ 0.16	$ 0.07

Net Income Per Share - Addition

Net Income Per Share - Additional Information (Detail) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Outstanding potential common shares excluded from computation of net income per share	4	126	1

Retirement Savings Plan - Addit

Retirement Savings Plan - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
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	$ 1,100,000	$ 733,000	$ 522,000

Selected Quarterly Financial 66

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, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 42,348	$ 40,354	$ 38,846	$ 36,970	$ 35,402	$ 32,506	$ 31,100	$ 28,939	$ 158,518	$ 127,947	$ 104,391
Gross profit	28,912	27,654	26,511	25,398	24,263	22,536	21,473	19,684	108,475	87,956	72,610
Income from operations	2,814	2,260	1,027	922	1,417	1,354	1,014	598	7,023	4,383	1,772
Net income	$ 2,132	$ 1,270	$ 651	$ 586	$ 854	$ 838	$ 639	$ 373	$ 4,639	$ 2,704	$ 1,051
Diluted earnings per share	$ 0.12	$ 0.07	$ 0.04	$ 0.03	$ 0.05	$ 0.05	$ 0.04	$ 0.02	$ 0.27	$ 0.16	$ 0.07

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) - USD ($) $ in Thousands	Jan. 05, 2016	Dec. 31, 2014
Subsequent Event [Line Items]
Stock issued for acquisition		$ 2,203
Toolbox Solutions, Inc. [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Payments to acquire business	$ 18,400
Stock issued for acquisition	$ 4,500
Stock issued for acquisition, Shares	64,891
Value of shares of common stock subject to earn-out and not yet issued	$ 1,100
Number of of shares of common stock subject to earn-out and not yet issued	16,222