Demandware (DWRE) 10-K 2 Mar 15 2014 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
In Billions, except Share data, unless otherwise specified	Dec. 31, 2014	Feb. 23, 2015	Jun. 30, 2014
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	FALSE
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Trading Symbol	DWRE
Entity Registrant Name	DEMANDWARE INC
Entity Central Index Key	1301031
Current Fiscal Year End Date	-19
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		36,498,602
Entity Public Float			$2.20

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$158,827	$242,425
Short-term investments	84,880	37,133
Accounts receivable-net of allowance for doubtful accounts of $525 and $459 at December 31, 2014 and 2013, respectively	42,441	28,402
Prepaid expenses and other current assets	8,564	4,315
Total current assets	294,712	312,275
Property and equipment, net	14,028	9,790
Goodwill	24,379	0
Intangible assets, net	10,266
Other assets	1,785	1,866
Total assets	345,170	323,931
Current liabilities:
Current portion of notes payable		2,727
Accounts payable	3,581	3,174
Accrued expenses	24,871	17,362
Deferred revenue	22,799	18,280
Other current liabilities	282	184
Total current liabilities	51,533	41,727
Long-term liabilities:
Deferred revenue	12,168	8,108
Notes payable		1,524
Other long-term liabilities	1,424	884
Total liabilities	65,125	52,243
Commitments and contingent liabilities (Note 12)
Redeemable noncontrolling interests	823
Stockholders' equity:
Preferred stock, $0.01 par value per share-10,000 shares authorized
Common stock, $0.01 par value per share-240,000 shares authorized; 35,281 and 34,268 shares issued and 35,279 and 34,268 shares outstanding at December 31, 2014 and 2013, respectively	353	343
Additional paid-in capital	391,896	356,766
Treasury stock, at cost (2 shares at December 31, 2014)	-137
Accumulated other comprehensive (loss) income	-352	64
Accumulated deficit	-112,538	-85,485
Total stockholders' equity	279,222	271,688
Total liabilities, redeemable noncontrolling interest and stockholders' equity	$345,170	$323,931

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$525	$459
Preferred stock, par value	$0.01	$0.01
Preferred stock, shares authorized	10,000,000	10,000,000
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	240,000,000	240,000,000
Common stock, shares issued	35,281,000	34,268,000
Common stock, shares outstanding	35,279,000	34,268,000
Treasury Stock, shares	2,000

Consolidated_Statements_of_Ope

Consolidated Statements of Operations and Comprehensive Loss (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue:
Subscription	$145,879	$95,733	$67,930
Services	14,674	10,881	15,347
Total revenue	160,553	106,614	83,277
Cost of revenue:
Subscription	26,933	17,157	13,015
Services	15,115	10,860	11,326
Total cost of revenue	42,048	28,017	24,341
Gross profit	118,505	78,597	58,936
Operating expenses:
Sales and marketing	74,432	52,384	33,496
Research and development	34,983	20,787	15,085
General and administrative	36,882	23,337	13,712
Total operating expenses	146,297	96,508	62,293
Loss from operations	-27,792	-17,911	-3,357
Other (expense) income:
Interest income	312	210	162
Interest expense	-108	-255	-355
Other (expense) income	-1,522	528	-351
Other (expense) income, net	-1,318	483	-544
Loss before income taxes	-29,110	-17,428	-3,901
Income tax (benefit) provision	-2,050	574	421
Net loss	-27,060	-18,002	-4,322
Net loss attributable to noncontrolling interest	7
Net loss attributable to Demandware	-27,053	-18,002	-4,322
Accretion of redeemable preferred stock			-1,172
Net loss attributable to Demandware common stockholders	-27,053	-18,002	-5,494
Net loss per share attributable to Demandware common stockholders, basic and diluted	($0.78)	($0.58)	($0.23)
Weighted average number of common shares outstanding, basic and diluted	34,806	30,795	24,063
Other comprehensive (loss) income:
Foreign currency translation adjustments	-405	93	22
Unrealized (loss) gain on marketable securities, net of tax	-11	-12	14
Total comprehensive loss	-27,476	-17,921	-4,286
Total comprehensive loss attributable to noncontrolling interest	7
Total comprehensive loss attributable to Demandware	($27,469)	($17,921)	($4,286)

Consolidated_Statements_of_Sto

Consolidated Statements of Stockholders' Equity (Deficit) (USD $)	Total	Common Stock $0.01 par value per share [Member]	Treasury Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Accumulated Deficit [Member]
In Thousands, except Share data
BALANCE at Dec. 31, 2011 (As Previously Reported [Member])	($84,620)	$45			($53)	($84,612)
BALANCE at Dec. 31, 2011	-79,217	45			-53	-79,209
BALANCE, Shares at Dec. 31, 2011 (As Previously Reported [Member])		4,469,000
BALANCE, Shares at Dec. 31, 2011		4,469,000
Prior period revision	5,403					5,403
Stock-based compensation	7,043			7,043
Exercise of common stock options	1,282	9		1,273
Exercise of common stock options, Shares		913,000
Accretion of preferred stock to redemption value	-1,172			-17,220		16,048
Vesting of restricted stock		1		-1
Vesting of restricted stock, Shares		86,000
Exercise of common stock warrant, Shares		20,000
Issuance of common stock in connection with initial public offering / public offering, net of issuance costs	90,837	63		90,774
Issuance of common stock in connection with initial public offering / public offering, Shares		6,325,000
Conversion of redeemable convertible preferred stock into common stock	88,775	180		88,595
Conversion of redeemable convertible preferred stock into common stock, Shares		18,029,000
Reclassification of a warrant to purchase shares of redeemable convertible preferred stock into a warrant to purchase common stock	533			533
Net loss	-4,322					-4,322
Other comprehensive income (loss)	36				36
BALANCE at Dec. 31, 2012	103,795	298		170,997	-17	-67,483
BALANCE, Shares at Dec. 31, 2012		29,842,000
Stock-based compensation	14,688			14,688
Exercise of common stock options	7,948	13		7,935
Exercise of common stock options, Shares		1,247,000
Vesting of restricted stock		2		-2
Vesting of restricted stock, Shares		167,000
Issuance of common stock through employee stock purchase program	544			544
Issuance of common stock through employee stock purchase program, Shares		15,000
Issuance of common stock in connection with initial public offering / public offering, net of issuance costs	162,634	30		162,604
Issuance of common stock in connection with initial public offering / public offering, Shares		2,997,000
Net loss	-18,002					-18,002
Other comprehensive income (loss)	81				81
BALANCE at Dec. 31, 2013	271,688	343		356,766	64	-85,485
BALANCE, Shares at Dec. 31, 2013		34,268,000
Stock-based compensation	26,348			26,348
Nonemployee stock-based compensation	553			553
Exercise of common stock options	6,848	6		6,842
Exercise of common stock options, Shares	572,000	572,000
Vesting of restricted stock		4		-4
Vesting of restricted stock, Shares		414,000
Issuance of common stock through employee stock purchase program	1,391			1,391
Issuance of common stock through employee stock purchase program, Shares		27,000
Treasury stock activity	-137		-137
Treasury stock activity, Shares	2,000		2,000
Net loss	-27,053					-27,053
Other comprehensive income (loss)	-416				-416
BALANCE at Dec. 31, 2014	279,222	353	-137	391,896	-352	-112,538
BALANCE, Shares at Dec. 31, 2014		35,281,000	2,000
BALANCE at Sep. 30, 2014
Treasury stock activity	-137		-137
Treasury stock activity, Shares	2,000		2,000
Net loss	-3,824
BALANCE at Dec. 31, 2014	$279,222		($137)
BALANCE, Shares at Dec. 31, 2014			2,000

Consolidated_Statements_of_Sto1

Consolidated Statements of Stockholders' Equity (Deficit) (Parenthetical) (Additional Paid-In Capital [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Additional Paid-In Capital [Member]
Issuance of common stock in connection with initial public offering / public offering, issuance costs	$482	$3,279

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	($27,060)	($18,002)	($4,322)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	6,601	4,385	3,439
Consulting expense settled with a restricted stock unit award	553
Re-measurement of preferred stock warrant liability			426
Bad debt expense	671	497
Stock-based compensation	26,630	14,688	7,043
Deferred income taxes	-2,798	65	-3
Amortization of premium on marketable securities	802	564	174
Deferred rent expense	141	-33	357
Write-off of other current asset		698
Other non-cash reconciling items	126	22	35
Changes in operating assets and liabilities:
Accounts receivable	-13,856	-9,684	-2,285
Prepaid expenses and other current assets	-4,207	-973	-1,011
Other long-term assets	-399	-525	203
Accounts payable	399	-274	1,016
Accrued expenses	7,971	8,843	1,224
Deferred revenue	8,045	8,841	-3,219
Net cash provided by operating activities	3,619	9,047	3,077
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of property and equipment	-9,162	-5,560	-3,846
Purchase of marketable securities	-132,750	-56,921	-63,239
Sale and maturity of marketable securities	84,191	67,464	14,828
Acquisition, net of cash acquired	-33,264
Increase in restricted cash and other assets	-18	-171	-357
Net cash (used in) provided by investing activities	-91,003	4,812	-52,614
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from initial public offering, net of underwriting discounts and commissions			94,116
Proceeds from follow-on public offering, net of underwriting discounts and commissions		162,634
Proceeds from shares purchased under Employee Stock Purchase Plan	1,391	544
Proceeds from exercise of stock options	6,848	7,948	1,282
Deferred offering costs			-1,604
Proceeds from issuance of notes payable		1,997	2,757
Payments of equipment notes	-3,345	-2,757	-2,674
Contribution from redeemable noncontrolling interests	830
Treasury stock repurchase	-137
Payments of software financing agreement	-766	-944	-471
Net cash provided by financing activities	4,821	169,422	93,406
EFFECT OF EXCHANGE RATES ON CASH AND CASH EQUIVALENTS	-1,035	267	69
(DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS	-83,598	183,548	43,938
CASH AND CASH EQUIVALENTS-Beginning of year	242,425	58,877	14,939
CASH AND CASH EQUIVALENTS-End of year	158,827	242,425	58,877
SUPPLEMENTARY INFORMATION:
Interest paid	101	242	282
Income taxes paid	759	297	200
NONCASH INVESTING AND FINANCING ACTIVITIES:
Conversion of redeemable convertible preferred stock to common stock			88,775
Conversion of preferred stock warrant to common stock warrant			533
Purchase of property and equipment included in accounts payable and accrued expenses	669	554	350
Software license acquired by assuming directly related liabilities			1,212
Software license technical support acquired by assuming directly related liabilities		$561	$549

Organization_and_Basis_of_Pres

Organization and Basis of Presentation	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Organization and Basis of Presentation	1. ORGANIZATION AND BASIS OF PRESENTATION
	Company Overview— Demandware, Inc. (the “Company”) provides enterprise-class cloud digital commerce solutions, which includes ecommerce, order management and predictive intelligence applications, for retailers and branded manufacturers. The Company’s solution, Demandware Commerce, is a combination of the Company’s cloud platform, community and related services that enables customers to establish and execute complex digital commerce strategies. These strategies include global expansion, multi-brand, multi-site rollouts, omni-channel and in-store operations as well as single platform, or unified commerce platform, strategies. The foundation of the Company’s solution is the Company’s technology platform, the Demandware Commerce Cloud. Through the Company’s highly scalable, secure and open Demandware Commerce Cloud, the Company’s customers create seamless brand experiences to reach their consumers across all digital touch points globally, including ecommerce sites, mobile applications, in-store solutions and point of sale.
	The Company sells subscriptions to its cloud software and related services through both a direct sales force and indirect channels. The Company’s current customers consist of retailers and branded manufacturers that operate principally in the following vertical markets: apparel and footwear, health and beauty, home and garden, sporting goods, general merchandise and other categories.
	The Company conducts its domestic operations through its headquarters in Burlington, Massachusetts and conducts its international operations through its direct and indirect subsidiaries in Germany, the United Kingdom, France, Sweden, Australia, China and Hong Kong and its joint venture in Japan.
	Basis of Presentation and Consolidation—The consolidated financial statements include the accounts of the Company and those entities in which it has a controlling interest. All intercompany transactions have been eliminated in consolidation.
	Changes in Presentation—Changes have been made to the presentation of deferred rent within the current and long-term liabilities of the consolidated balance sheets as these amounts are now included in other current liabilities and other long-term liabilities, respectively. Additionally, amortization of premium on marketable securities in the consolidated statement of cash flows previously included in other non-cash reconciling items is now presented as a separate line item in the current year presentation.
	Correction of Immaterial Errors—In the fourth quarter of 2014, the Company conducted a reevaluation of its revenue recognition policy for implementation services. The Company determined that certain implementation services have standalone value and therefore it is appropriate to recognize revenue for these implementation services as the services are delivered, assuming all other revenue recognition criteria have been met. The Company has concluded that the revenue recognition policy previously applied beginning in 2011 for these implementation services, which deferred recognition of the related revenue ratably over the longer of the term of the subscription agreement or estimated expected life of the customer relationship, was inappropriate. Accordingly, the Company has corrected its accounting policy for service revenue recognition. The Company has concluded that the correction of the errors was not material to any of the previously issued annual or interim financial statements. However, to facilitate period-over-period comparisons, the Company has revised its previously issued financial statements contained in this Annual Report on Form 10-K to reflect the corrections of these immaterial errors for the corresponding periods.
	The following table presents the impact of these corrections on its consolidated statements of operations and comprehensive loss for the years ended December 31, 2013 and 2012 (in thousands, except per share data):
		For the Year Ended December 31, 2013									For the Year Ended December 31, 2012
		As Previously			Adjustment			As Revised			As Previously			Adjustment		As Revised
		Reported									Reported
	Revenue:
	Services	$	8,003		$	2,878		$	10,881		$	11,545		$	3,802	$	15,347
	Total revenue		103,736			2,878			106,614			79,475			3,802		83,277
	Gross profit		75,719			2,878			78,597			55,134			3,802		58,936
	Net loss	$	(20,880	)	$	2,878		$	(18,002	)	$	(8,124	)	$	3,802	$	(4,322	)
	Net loss attributable to common stockholders	$	(20,880	)	$	2,878		$	(18,002	)	$	(9,296	)	$	3,802	$	(5,494	)
	Net loss per share attributable to common stockholders, basic and diluted	$	(0.68	)	$	0.1		$	(0.58	)	$	(0.39	)	$	0.16	$	(0.23	)
	Comprehensive loss	$	(20,799	)	$	2,878		$	(17,921	)	$	(8,088	)	$	3,802	$	(4,286	)
	The following table presents the impact of these corrections on its consolidated balance sheet items as of December 31, 2013 (in thousands):
		For the Year Ended December 31, 2013
		As  Previously			Adjustment			As Revised
		Reported
	Current liabilities:
	Deferred revenue	$	19,609		$	(1,329	)	$	18,280
	Total current liabilities	$	43,056		$	(1,329	)	$	41,727
	Long-term liabilities:
	Deferred revenue	$	18,862		$	(10,754	)	$	8,108
	Total liabilities:	$	64,326		$	(12,083	)	$	52,243
	Stockholders’ equity:
	Accumulated deficit	$	(97,568	)	$	12,083		$	(85,485	)
	Total stockholders’ equity:	$	259,605		$	12,083		$	271,688
	Total liabilities and stockholders’ equity:	$	323,931		$	—		$	323,931
	The impact of these corrections on its consolidated statements of cash flows for the years ended December 31, 2013 and 2012 were decreases to the Company’s net losses and decreases in the change of deferred revenue by $2.9 million and $3.8 million, respectively, within cash flows from operating activities. There was no change to the total net cash provided by operating activities for the years ended December 31, 2013 and 2012.
	The effect of the error in the statement of operations for the year ended December 31, 2011 was an increase to service revenue and total revenue of $5.4 million and a change from a net loss of $6.7 million to a net loss of $1.3 million. Net loss per share attributable to common stockholders, basic and diluted, decreased from $1.75 per share to $0.34 per share for the year ended December 31, 2011. Total deferred revenue and accumulated deficit decreased by $9.2 million and $5.4 million at December 31, 2012 and 2011, respectively. Working capital increased by $0.9 million and $0.4 million at December 31, 2012 and 2011, respectively.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	Use of Estimates—The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (“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 revenue, cost of revenue, and expenses during the reporting period. Actual results could differ from those estimates.
	Foreign Currency Translation—The functional currency of the Company’s foreign subsidiaries is the local currency. All assets and liabilities denominated in a foreign currency are translated into U.S. dollars at the exchange rate on the balance sheet date. Revenue and expenses are translated at the average exchange rate during the period. Translation gains or losses are included as a component of accumulated other comprehensive (loss) income in stockholders’ equity (deficit). Transaction gains or losses that arise from exchange rate fluctuations on transactions denominated in a currency other than the functional currency are included in other income (expense) in the accompanying consolidated results of operations as incurred. For the years ended December 31, 2014, 2013 and 2012, foreign currency transaction (losses) gains of ($1.7) million, $0.6 million, and $0.1 million, respectively, are included in other expenses in the accompanying consolidated statements of operations and comprehensive loss.
	Business Combination—The Company allocates the purchase price to the assets acquired and the liabilities assumed at their estimated fair values as of the date of the acquisition with any excess of the purchase price paid over the estimated fair value of net assets acquired recorded as goodwill. The fair value of the assets acquired and liabilities assumed is typically determined by using either estimates of replacement costs or multiple period excess earnings methods. Contingent payments that are dependent upon post-combination services, if any, are considered separate transactions outside of the business combination and therefore included in the post-combination operating results. Transaction costs in connection with the acquisition are recorded as operating expenses.
	Cash Equivalents and Short-Term Investments—The Company considers all highly liquid investments maturing within 90 days from the date of purchase to be the equivalent of cash for the purpose of balance sheet and statement of cash flows presentation. As of December 31, 2014, $140.1 million of the Company’s cash equivalents were invested in money market funds, and $2.5 million in marketable securities. As of December 31, 2013, $226.1 million of the Company’s cash equivalents were invested in money market funds and $3.0 million in marketable securities.
	Short-term investments in marketable securities are classified as available-for-sale and mature within 12 months from the date of purchase. The Company’s investments in marketable securities are recorded at fair value, with any unrealized gains and losses, net of taxes, reported as a component of stockholders’ equity until realized or until a determination is made that an other-than-temporary decline in market value has occurred. When the Company determines that an other-than-temporary decline has occurred for debt securities that the Company does not then intend to sell, the Company recognizes the credit loss component of an other-than-temporary impairment in other income (expense) and the remaining portion in other comprehensive loss. The credit loss component is identified as the amount of the present value of cash flows not expected to be received over the remaining term of the security, based on cash flow projections. In determining whether an other-than-temporary impairment exists, the Company considers: (i) the length of time and the extent to which the fair value has been less than cost; (ii) the financial condition and near-term prospects of the issuer of the securities; and (iii) the Company’s intent and ability to retain the security for a period of time sufficient to allow for any anticipated recovery in fair value. The cost of marketable securities sold is determined based on the specific identification method and any realized gains or losses on the sale of investments are reflected as a component of interest income or expense.
	Accounts Receivable—Accounts receivable represent trade receivables from customers when the Company has invoiced for software subscriptions and/or services and it has not yet received payment. The Company maintains an allowance for doubtful accounts for the estimated probable losses on uncollectible accounts receivable, and presents accounts receivable net of this allowance. The allowance is based upon a number of factors including the credit worthiness of customers, the Company’s historical experience with customers, the age of the receivable and current market and economic conditions. Such factors are reviewed and updated by the Company on a quarterly basis. Account balances are written off against the allowance after all means of collection have been exhausted and the potential for recovery is considered remote.
	Activity within the allowance for doubtful accounts is as follows, (in thousands):
		Years Ended December 31,
		2014			2013			2012
	Balance at beginning of year	$	459		$	—		$	—
	Charges		671			497			—
	Write-offs		(605	)		(38	)		—
	Balance at end of year	$	525		$	459		$	—
	Derivative Instruments—The Company is exposed to foreign currency exchange rate risk relating to its ongoing business operations. Forward contracts on various foreign currencies are entered into to manage the foreign currency exchange rate risk and are intended to offset economic exposures of the Company. The Company does not use derivative financial instruments for trading or speculative purposes. The Company does not designate these forward contracts as hedging instruments and these contracts are carried at fair value with changes in value recorded in operations. Cash flows from these forward contracts are reported in the consolidated statement of cash flows under cash flows from operating activities. See Note 6 for further discussion.
	Concentrations of Credit Risk and Significant Customers—Financial instruments that potentially expose the Company to concentrations of credit risk include cash, cash equivalents, marketable securities, foreign currency forward contracts and accounts receivable. The Company maintains substantially all of its cash, cash equivalents, marketable securities and foreign currency forward contracts with financial institutions that management believes have high credit standings. To manage credit risk related to accounts receivable, the Company evaluates the allowances for potential credit losses. To date, losses resulting from uncollected receivables have not exceeded management’s expectations.
	As of December 31, 2014, no single customer comprised more than 10% of accounts receivable. As of December 31, 2013, the Company had one reseller representing 12% of accounts receivable. During the years ended December 31, 2014, 2013, and 2012, no single customer comprised more than 10% of the Company’s revenue.
	Property and Equipment—Property and equipment are recorded at cost and depreciated using the straight-line method over the estimated useful lives of the related assets, which ranges from three to five years. Leasehold improvements are amortized over the lesser of the term of the lease or the useful life of the asset. When assets are retired or disposed of, the assets and related accumulated depreciation are eliminated from the accounts and any resulting gain or loss is included in the determination of net income or loss. Maintenance and repair expenditures are charged to expense as incurred.
	Research and Development and Internal Use Software—Research and development expenses consist primarily of personnel and related expenses for the Company’s research and development staff, including salaries, benefits, bonuses and stock-based compensation and the cost of certain third party contractor costs. Expenditures for research and development, other than internal use software costs, are expensed as incurred.
	Software development costs associated with internal use software are capitalized when the preliminary project stage is completed, management has decided to make the project a part of its future offering, and the software will be used to perform the function intended. These capitalized costs include external direct costs of services consumed in developing or obtaining internal-use software, personnel and related expenses for employees who are directly associated with and who devote time to internal-use software projects. Capitalization of these costs cease once the project is substantially complete and the software is ready for its intended purpose. Post-configuration training and maintenance costs are expensed as incurred. Capitalized internal use software costs are amortized to cost of revenue using a straight-line method over its estimated useful life of four years, commencing when the software is ready for its intended use.
	During the years ended December 31, 2014 and 2013, no internal use software development cost was capitalized. During the year ended December 31, 2012, $0.2 million of internal use software development cost was capitalized. Capitalized internal use software is included in property and equipment.
	Amortization expense related to internal use software totaled $0.2 million, $0.2 million and $0.1 during the years ended December 31, 2014, 2013 and 2012, respectively. The net book value of capitalized internal use software at December 31, 2014 and 2013 was $0.4 million and $0.6 million, respectively.
	Segment and Geographic Information—Operating segments are defined as components of an enterprise for which discrete financial information is available that is evaluated on a regular basis by the chief operating decision maker, or decision making group, in deciding how to allocate resources and assess performance. The Company’s chief operating decision maker (“CODM”) is the Chief Executive Officer. The CODM reviews consolidated operating results to make decisions about allocating resources and assessing performance for the entire Company. The CODM views the Company’s operations and manages its business as one operating segment.
	Information about the Company’s operations in different geographic regions is presented in the tables below (in thousands):
		Year Ended December 31,
		2014			2013			2012
					(As revised)			(As revised)
	Revenue:
	United States	$	99,085		$	63,155		$	47,147
	Germany		22,218			16,521			20,578
	United Kingdom		18,328			13,130			9,100
	All other international		20,922			13,808			6,452
	Total revenue	$	160,553		$	106,614		$	83,277
	Long-lived assets (at year end):
	United States		23,214			8,814			7,976
	Germany		455			362			303
	United Kingdom		429			554			15
	All other international		196			60			83
	Total long-lived assets	$	24,294		$	9,790		$	8,377
	Goodwill and Purchased Intangible Assets—Goodwill represents the excess of the purchase price in a business combination over the fair value of net tangible and intangible assets acquired. Goodwill is reviewed for impairment at least annually or whenever events or changes in circumstances indicate that the carrying value of the goodwill may not be recoverable. The Company’s annual impairment assessment date is November 30 of each fiscal year. The Company has determined that there is a single reporting unit for the purpose of goodwill impairment tests. The Company utilizes the two-step impairment test when testing goodwill for impairment. Under the first step of this test, the Company compares the fair value of the entity to its carrying value. If the carrying value exceeds the fair value, the Company conducts the second step of this test, in which the implied fair value of the goodwill is compared to its carrying amount. If the carrying amount of goodwill exceeds its implied fair value, an impairment loss would be recognized for the amount of the excess. During the year ended December 31, 2014, no potential impairment was identified under the first step of the test as the fair value of the entity was in excess of its carrying value. There was no goodwill at December 31, 2013.
	Purchased intangible assets represent those acquired from business combinations and are deemed to have a definite life. They are amortized over their useful lives, generally ranging from three to five years. The Company evaluates intangible assets for impairment whenever events or changes in circumstances indicate the carrying value of an asset or asset group may not be recoverable. During the year ended December 31, 2014, no such impairment indicator was identified. There were no purchased intangible assets at December 31, 2013.
	Revenue Recognition—The Company generates revenue from sales of its digital commerce solutions that leverage its proprietary technology, which are represented by subscription fees for its ecommerce, order management and predictive intelligence solutions, activation fees and related professional services. Professional services include implementation services, consulting services to support its customers once they are live on the Company’s solution and training.
	The Company recognizes revenue when persuasive evidence of an arrangement exists, delivery to customers has occurred or services have been rendered, the fee is fixed or determinable, and collectability is reasonably assured. The Company does not recognize revenue in excess of the amounts for which it has the right to invoice in an annual subscription year.
	In most instances, revenue from new customer acquisition is generated under sales agreements with multiple elements, comprised of subscription fees, related activation fees that allow customers to access the solutions, and professional services. The Company evaluates each element in a multiple-element arrangement to determine whether it represents a separate unit of accounting. An element constitutes a separate unit of accounting when the delivered item has standalone value and delivery of the undelivered element is probable and within the Company’s control. Subscriptions have standalone value because they are routinely sold separately by the Company.
	Other than the Company’s site readiness assessment offering, the Company’s professional services have standalone value because the Company has sold professional services separately or there are third party vendors that routinely provide similar professional services to its customers on a standalone basis. The Company does not have evidence of standalone value for site readiness assessments because they are not sold on a standalone basis and can only be provided by the Company.
	Activation fees provide access to the Company’s digital environment through production launch and are billed during the implementation phase and recorded as deferred revenue until a customer’s subscription period has commenced. Activation fees do not have standalone value because they are only sold in conjunction with a subscription to our ecommerce solutions, they are only sold by the Company, a customer could not resell it, and they do not represent the culmination of a separate earnings process.
	The Company allocates revenue to each element in an arrangement based on a selling price hierarchy. The selling price for a deliverable is based on its vendor-specific objective evidence (“VSOE”), if available, third party evidence (“TPE”), if VSOE is not available, or best estimated selling price (“BESP”), if neither VSOE nor TPE is available. As the Company has been unable to establish VSOE or TPE for the elements of its arrangements, the Company establishes the BESP for each element primarily by considering the weighted average of actual sales prices of professional services sold on a standalone basis and subscriptions including various add-on modules when sold together without professional services, and other factors such as gross margin objectives, pricing practices and growth strategy.
	Subscriptions include fees derived from contractually committed minimum levels of gross revenue processed by ecommerce customers on the Company’s cloud digital commerce platform, and fees derived from such customers’ gross revenue processed above the minimum contracted levels. Customers do not have the contractual right to take possession of the Company’s cloud software. The consideration allocated to the subscription for the aggregate minimum subscription fee is recognized on a straight-line basis over the subscription term once a customer’s subscription period has commenced. Should an ecommerce customer exceed the specified minimum levels of gross revenue processed, fees for customer gross revenue processed in excess of the committed minimum level are billed for the excess volume. The Company recognizes revenue from the fees it receives for its customers’ gross revenue processed in excess of the committed minimum level in the period in which such gross revenue is processed and earned.
	Activation fees and site readiness assessments without standalone value are recognized ratably over the longer of the life of the agreement or the expected customer life, which is currently estimated to be just over six years. The Company evaluates the length of the amortization period based on our experience with customer contract renewals and consideration of the period over which those customers will benefit from the related offerings.
	The consideration allocated to professional services with standalone value is recognized as revenue using the proportional performance method.
	Deferred revenue primarily consists of the unearned portion of billed subscription and services fees. Once a customer’s subscription period has commenced, the Company typically invoices customers on a monthly or quarterly basis. In addition, the Company often invoices the first year subscription fee in advance upon customer contract execution as an initiation payment. Initiation payments are included in deferred revenue upon payment.
	Reimbursable costs received for out-of-pocket expenses are recorded as revenue and cost of revenue in the consolidated statements of operations and comprehensive loss. Sales taxes collected from customers and remitted to government authorities are excluded from revenue.
	Cost of Revenue—Cost of subscription revenue primarily consists of hosting costs, data communications expenses, depreciation expenses associated with computer equipment, personnel and related costs, including salaries, bonuses, payroll taxes, recruiting fees and stock compensation, software license fees and amortization expenses associated with capitalized software. In addition, the Company allocates a portion of overhead, such as rent, IT costs, depreciation and amortization and employee benefits costs, to cost of revenue based on headcount.
	Cost of services revenue primarily consists of personnel and related costs, third party contractors and allocated overhead. The Company’s cost of services revenue is expensed as the costs are incurred.
	Impairment of Long-Lived Assets—The Company considers whether indicators of impairment of its long-lived assets are present. If such indicators are present, the Company determines whether the sum of the estimated undiscounted future cash flows attributable to such assets is less than their carrying amount, and if so, the Company recognizes an impairment loss based on the excess of the carrying amount of the assets over their fair value. To date, no such impairment has occurred.
	Advertising—Advertising costs are charged to operations as incurred and include direct marketing, events, public relations, sales collateral materials and partner programs. Advertising expense was approximately $8.4 million, $6.2 million and $4.0 million for the years ended December 31, 2014, 2013 and 2012, respectively.
	Income Taxes—Deferred tax assets and liabilities are recognized based on temporary differences between the financial reporting and income tax bases of assets and liabilities using rates anticipated to be in effect when such temporary differences reverse. A valuation allowance against deferred tax assets is recorded, based upon the available evidence, if it is more likely than not that some or all of the deferred tax assets will not be realized. The Company assesses its income tax positions and records tax benefits based upon management’s evaluation of the facts, circumstances, and information available at the reporting date. For those tax positions where it is more likely than not that a tax benefit will be sustained, the Company records the largest amount of tax benefit with a greater than 50 percent likelihood of being realized upon ultimate settlement with a taxing authority having full knowledge of all relevant information. For those income tax positions where it is not more likely than not that a tax benefit will be sustained, no tax benefit is recognized in the financial statements. The unrecognized tax benefits are currently presented as a reduction to the deferred tax assets in the financial statements, unless the uncertainty is expected to be resolved within one year. Potential interest and penalties associated with such uncertain tax positions are recorded as a component of income tax expense.
	Stock-Based Compensation—The Company accounts for all stock options granted to employees and nonemployees using a fair value method. The Black-Scholes option pricing model is used to determine the fair value of the award, which is then recognized on a straight-line basis over the requisite services period, which is the vesting period of the award. The measurement date for employee awards is the date of the grant, and the measurement date for nonemployee awards is the date the performance or services are completed.
	Other Comprehensive (Loss) Income—Other comprehensive (loss) income consists of foreign currency translation adjustments and unrealized gains or losses on marketable securities.
	Warranties—The Company includes service level commitments to its customers warranting certain levels of uptime reliability and performance and permitting those customers to receive credits in the event that the Company fails to meet those levels. To date, the Company has not incurred any material costs as a result of such commitments.
	Commissions—The Company recognizes commission expense related to subscriptions in the period in which the contract is signed.
	Recent Accounting Pronouncements—
	In May 2014, the Financial Accounting Standards Board issued Accounting Standards Update (“ASU”) No. 2014-09, “Revenue from Contracts with Customers”. The comprehensive new standard will supersede existing revenue recognition guidance and require revenue to be recognized when promised goods or services are transferred to customers in amounts that reflect the consideration to which the Company expects to be entitled in exchange for those goods or services. The guidance will also require that certain contract costs incurred to obtain or fulfill a contract, such as sales commissions, be capitalized as an asset and amortized as revenue is recognized. Adoption of the new rules could affect the timing of both revenue recognition and the recognition of contract costs for certain transactions. The guidance permits two implementation approaches, one requiring retrospective application of the new standard with restatement of prior years and one requiring prospective application of the new standard with disclosure of results under old standards. For the Company, the new standard will be effective January 1, 2017. The Company is currently evaluating the impact of adoption and the implementation approach to be used.

Net_Loss_Per_Share_Attributabl

Net Loss Per Share Attributable to Common Shareholders	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Net Loss Per Share Attributable to Common Shareholders	3. NET LOSS PER SHARE ATTRIBUTABLE TO COMMON SHAREHOLDERS
	The Company calculates basic and diluted net loss per common share by dividing the net loss by the weighted average number of common shares outstanding during the period. The Company has excluded all potentially dilutive shares, which include outstanding common stock options and unvested restricted stock, from the weighted average number of common shares outstanding as their inclusion in the computation for all periods would be anti-dilutive due to net losses. The Company’s unvested restricted stock awards are not considered participating securities under the authoritative guidance since any dividends earned on unvested restricted shares are required to be returned if unvested shares are forfeited. The following common stock equivalents were excluded from the computation of diluted net loss per share attributable to common stockholders because they had an antidilutive impact (in thousands):
		Year Ended December 31,
		2014		2013		2012
	Options to purchase common stock		2,586		3,652		4,421
	Nonvested restricted stock		1,194		880		341

Business_Combination

Business Combination	12 Months Ended
	Dec. 31, 2014
Business Combinations [Abstract]
Business Combination	4. BUSINESS COMBINATION
	Mainstreet Commerce LC—On January 22, 2014, the Company acquired 100% of the equity of Mainstreet Commerce LC (“Mainstreet”), a provider of cloud-based distributed order management solutions, for total cash consideration of $19.4 million, of which $10.0 million was held in escrow and is being released ratably in quarterly payments through January 2016. $7.0 million of the amount in escrow is reserved for payments to key Mainstreet employees for post-combination employment services, and therefore is recorded as a prepayment in the Company’s consolidated balance sheet, and will be recognized in the Company’s post-combination financial statements as compensation expense over the employment period. The remaining $3.0 million in escrow is being withheld following the close of the transaction as protection against certain losses the Company may incur in the event of certain breaches of representations, warranties and covenants and other specified claims set forth in the purchase agreement, and therefore is included in the purchase price of $12.4 million. For the year ended December 31, 2014, the Company incurred transaction costs in connection with the acquisition of $0.1 million, which are included in general and administrative expenses.
	Under the acquisition method of accounting, the Company allocated the purchase price to the identifiable assets and liabilities based on their estimated fair value, which was determined by management using the information available as of the date of the acquisition (Level 3 inputs). The allocation of the Mainstreet purchase consideration to the assets acquired and liabilities assumed was as follows (in thousands):
	Cash	$	261
	Accounts receivable		511
	Developed technology		2,500
	Customer relationships		300
	Trademarks		10
	Goodwill		8,966
	Other assets / liabilities, net		(151	)
	Total purchase consideration	$	12,397
	Methodologies used in valuing the intangible assets include, but are not limited to, the replacement cost method for customer relationships, relief from royalty for trademarks and multiple period excess earnings method for developed technology. The excess of the purchase price over the total net identifiable assets has been recorded as goodwill, which includes synergies expected from the expanded service capabilities and the value of the assembled work force in accordance with GAAP. For federal income tax purposes, the transaction is treated as an asset acquisition. The goodwill resulting from this transaction is expected to be deductible for tax purposes.
	CQuotient, Inc.—On October 9, 2014, the Company acquired 100% of the equity of CQuotient, Inc. (“CQuotient”), a cloud personalization provider, for cash consideration of approximately $21.5 million, of which $3.2 million was held in escrow to secure certain indemnification and other obligations of the sellers and is going to be released 18 months from the acquisition date. Additional consideration of up to $3.4 million, payable in cash or shares of the Company’s common stock at the option of the Company, is payable to certain employees in 2 to 3 years contingent upon their continued employment. This consideration will be recognized in the Company’s post-combination financial statements as compensation expense over the employment period. For the year ended December 31, 2014, the Company incurred transaction costs in connection with the acquisition of $0.4 million, which are included in general and administrative expenses.
	Under the acquisition method of accounting, the Company allocated the purchase price to the identifiable assets and liabilities based on their estimated fair value, which was determined by management using the information available as of the date of the acquisition (Level 3 inputs). The allocation of the CQuotient purchase consideration to the assets acquired and liabilities assumed was as follows (in thousands):
	Cash	$	353
	Accounts receivable		343
	Developed technology		8,500
	Customer relationships		300
	Deferred revenue		(366	)
	Deferred tax liabilities		(3,020	)
	Goodwill		15,413
	Other assets / liabilities, net		(42	)
	Total purchase consideration	$	21,481
	Methodologies used in valuing the intangible assets include, but are not limited to, the replacement cost method for customer relationships and multiple period excess earnings method for developed technology. The excess of the purchase price over the total net identifiable assets has been recorded as goodwill, which includes synergies expected from the expanded service capabilities and the value of the assembled work force in accordance with GAAP. For federal income tax purposes, the transaction is treated as a stock acquisition. The goodwill resulting from this transaction is not expected to be deductible for tax purposes.
	The Company has not furnished pro forma financial information related to these acquisitions because they are not material, individually or in the aggregate, to the Company’s consolidated results of operations. The Company has not disclosed the amounts of revenue and earnings of these acquirees included in the consolidated statement of operations for the year ended December 31, 2014 since the acquisition date because they are not material, individually and in the aggregate, to the Company’s consolidated results of operations.

Cash_Equivalents_and_ShortTerm

Cash Equivalents and Short-Term Investments	12 Months Ended
	Dec. 31, 2014
Cash and Cash Equivalents [Abstract]
Cash Equivalents and Short-Term Investments	5. CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS
	A summary of the Company’s cash equivalents and short-term investments at December 31, 2014 is as follows (in thousands):
		Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
	Cash Equivalents:
	Money market funds	$	140,107	$	—	$	—		$	140,107
	Certificates of deposit		498		—		—			498
	Municipal securities		2,015		—		—			2,015
		$	142,620	$	—	$	—		$	142,620
	Short-Term Investments:
	U.S. government agency bonds	$	21,304	$	1	$	(2	)	$	21,303
	Corporate bonds		6,895		—		(3	)		6,892
	Municipal securities		29,383		2		(7	)		29,378
	Certificates of deposit		27,307		—		—			27,307
		$	84,889	$	3	$	(12	)	$	84,880
	A summary of the Company’s cash equivalents and short-term investments at December 31, 2013 is as follows (in thousands):
		Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
	Cash Equivalents:
	Money market funds	$	226,130	$	—	$	—		$	226,130
	Certificates of deposit		998		—		—			998
	Municipal securities		2,000		—		—			2,000
		$	229,128	$	—	$	—		$	229,128
	Short-Term Investments:
	U.S. government agency bonds	$	4,500	$	1	$	—		$	4,501
	Corporate bonds and commercial paper		3,318		—		(1	)		3,317
	Municipal securities		19,701		4		(2	)		19,703
	Certificates of deposit		9,612		1		(1	)		9,612
		$	37,131	$	6	$	(4	)	$	37,133
	The contractual maturity dates for the Company’s available-for-sale investments that are classified as short-term investments in the consolidated balance sheets are one year or less from the respective balance sheet dates.

Derivative_Instruments

Derivative Instruments	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	6. DERIVATIVE INSTRUMENTS
	The Company conducts business in a number of foreign countries and transacts business in various foreign currencies. Foreign currency exposures typically arise from transactions denominated in a currency other than the functional currency. The Company utilizes foreign currency forward contracts to offset the risks associated with the effect of certain foreign currency exposures. These contracts are entered into so that increases or decreases in the Company’s foreign currency exposures are offset by gains or losses on the forward contracts in order to mitigate the risks and volatility associated with the Company’s foreign currency transactions. The Company had the following outstanding foreign currency forward contracts as of December 31, 2014 and 2013 (in thousands):
		December 31, 2014				December 31, 2013
	Currency	Notional		USD		Notional		USD
		Value		Equivalent		Value		Equivalent
	Euro		6,500	$	7,901		—	$	—
	British Pounds Sterling		3,000	$	4,660		—	$	—
	The Company has not designated these forward contracts as hedging instruments pursuant to ASC 815, Derivatives and Hedging, and accordingly, the Company recorded the fair value of these contracts at the end of each reporting period in our consolidated balance sheet, with changes in the fair value recorded in earnings as other income (expense), net in the Company’s consolidated statements of operations and comprehensive loss. The fair value of the forward contracts at December 31, 2014 was $69,000 and was recorded in prepaid expenses and other current assets on the balance sheet. The unrealized gain from the forward contracts recognized for the year ended December 31, 2014 was $69,000 and was recorded in other (expense) income on the statement of operations and comprehensive loss. There was no outstanding forward contract at December 31, 2013 and no unrealized gain or loss was recognized related to forward contracts for the years ended December 31, 2013 and 2012.

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Fair Value Measurements	7. FAIR VALUE MEASUREMENTS
	Financial instruments, including cash equivalents, accounts receivable, accounts payable, and accrued expenses are carried in the consolidated financial statements at amounts that approximate fair value at December 31, 2014 and 2013. Fair values are based on market prices and assumptions concerning the amount and timing of estimated future cash flows and assumed discount rates, reflecting varying degrees of perceived risk. Management believes that the Company’s debt obligations bear interest at rates which approximate prevailing market rates for instruments with similar characteristics and, accordingly, the carrying values for these instruments approximate fair value.
	GAAP defines fair value as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants at the measurement date. Additionally, the inputs used to measure fair value are prioritized based on a three-level hierarchy. This hierarchy requires entities to maximize the use of observable inputs and minimize the use of unobservable inputs. The three levels of inputs used to measure fair value are as follows:
		•		Level 1—Quoted prices in active markets for identical assets or liabilities.
		•		Level 2—Other inputs that are observable directly or indirectly, such as quoted prices for similar assets and liabilities or market corroborated inputs.
		•		Level 3—Unobservable inputs are used when little or no market data is available, which requires the Company to develop its own assumptions about how market participants would value the assets or liabilities.
	The following table details the fair value measurements within the fair value hierarchy of the Company’s financial assets and liabilities at December 31, 2014 and 2013 (in thousands):
					Fair Value Measurements Using
			Amounts		Quoted Prices		Significant Other		Significant
			at Fair Value		in Active		Observable Inputs		Unobservable
					Markets for		(Level 2)		Inputs (Level 3)
					Identical Assets
					(Level 1)
	At December 31, 2014
	Assets—Cash Equivalents:
	Money market funds		$	140,107	$	140,107	$	—	$	—
	Certificates of deposit			498		—		498		—
	Municipal securities			2,015		—		2,015		—
	Assets—Short-Term Investments:
	U.S. government agency bonds		$	21,303	$	—	$	21,303	$	—
	Corporate bonds			6,892		—		6,892		—
	Municipal securities			29,378		—		29,378		—
	Certificates of deposit			27,307		—		27,307		—
	Assets—Derivative Instruments:
	Foreign currency forward contracts		$	69	$	—	$	69	$	—
	At December 31, 2013
	Assets—Cash Equivalents:
	Money market funds		$	226,130	$	226,130	$	—	$	—
	Certificates of deposit			998		—		998		—
	Municipal securities			2,000		—		2,000		—
	Assets—Short-Term Investments:
	U.S. government agency bonds		$	4,501	$	—	$	4,501	$	—
	Corporate bonds and commercial paper			3,317		—		3,317		—
	Municipal securities			19,703		—		19,703		—
	Certificates of deposit			9,612		—		9,612		—
	When developing fair value estimates, the Company maximizes the use of observable inputs and minimizes the use of unobservable inputs. When available, the Company uses quoted market prices to measure fair value. If market prices are not available, the fair value measurement is based on models that use primarily market based parameters including yield curves, volatilities, credit ratings and currency rates. In certain cases where market rate assumptions are not available, the Company is required to make judgments about assumptions market participants would use to estimate the fair value of a financial instrument.
	The valuation technique used to measure fair value for the Company’s Level 1 and Level 2 assets and liabilities is a market approach that uses prices and other relevant information generated by market transactions involving identical or comparable assets. There were no Level 3 financial assets or liabilities at December 31, 2014 and 2013.

Property_and_Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Property and Equipment	8. PROPERTY AND EQUIPMENT
	Property and equipment as of December 31, 2014 and 2013 consist of the following (in thousands):
		December 31,
		2014			2013
	Computer equipment	$	24,700		$	18,976
	Purchased software, including internal use software		6,742			4,134
	Leasehold improvements		1,078			893
	Office furniture		1,352			1,177
	Property and equipment—at cost		33,872			25,180
	Less: accumulated depreciation and amortization		(19,844	)		(15,390	)
	Property and equipment—net	$	14,028		$	9,790
	Depreciation and amortization expense for the years ended December 31, 2014, 2013 and 2012, was $5.3 million, $4.4 million and $3.4 million, respectively.

Goodwill_and_Purchased_Intangi

Goodwill and Purchased Intangible Assets	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Purchased Intangible Assets	9. GOODWILL AND PURCHASED INTANGIBLE ASSETS
	Goodwill—Changes in the carrying amount of goodwill in the year ended December 31, 2014 are as follows (in thousands):
	Balance, December 31, 2013	$	—
	Additions		24,379
	Balance, December 31, 2014	$	24,379
	The addition to goodwill during fiscal year 2014 is related to the acquisition of Mainstreet in January 2014 and CQuotient in October 2014 (see Note 4).
	Purchased Intangible Assets—Intangible assets acquired as of December 31, 2014 are as follows (in thousands):
				As of December 31, 2014
		Weighted Average		Gross Carrying		Accumulated		Net Book Value
		Life (Years)		Amount		Amortization
	Developed technology		5	$	11,000	$	1,242	$	9,758
	Customer relationships		4		600		92		508
	Trademarks		1		10		10		—
	Total		4.9	$	11,610	$	1,344	$	10,266
	The Company had no acquired intangible assets as of December 31, 2013.
	Amortization expense related to acquired intangible assets was $1.3 million for the fiscal year ended December 31, 2014. The Company incurred no amortization expense related to acquired intangible assets for the year ended December 31, 2013.
	Future estimated amortization expense for acquired intangible assets as of December 31, 2014 is as follows (in thousands):
	2015	$	2,474
	2016		2,277
	2017		2,179
	2018		2,002
	2019		1,334
	Total	$	10,266

Debt

Debt	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
Debt	10. DEBT
	Line of Credit—The Company’s loan and security agreement (the “2008 Loan Agreement”) provided a secured revolving credit facility of up to $5.0 million (the “Revolving Credit Facility”). Under the terms of the agreement, borrowing availability varied based upon eligible accounts receivable. Borrowings were collateralized by substantially all of the assets of the Company and bore interest at a variable rate of 0.75% above prime rate. The Revolving Credit Facility was terminated by the Company in June 2012 at the Company’s request pursuant to the terms of the 2008 Loan Agreement. At December 31, 2014, there was no borrowing availability under the Revolving Credit Facility.
	In connection with the Company’s entry into the 2008 Loan Agreement, the Company issued a warrant to purchase 23,092 shares of its Series C Preferred Stock, which, at the closing of the IPO, automatically converted into a warrant to purchase shares of the Company’s common stock at an exercise price of $3.90 per share. The warrant was net exercised in September 2012 resulting in the issuance of 20,186 shares of common stock (see Note 14).
	Equipment Notes Payable—The Company’s loan and security agreement included an equipment line of credit (the “Loan”). Borrowings under the Loan could be made for eligible equipment purchases. Each advance under the Loan was payable in 36 equal monthly payments of principal plus accrued interest, at an annual rate of 3.75%. In September 2014, the Company paid the outstanding balance in full.
	As of December 31, 2014 and 2013, the outstanding balance under the Loan was zero and $3.3 million, respectively. The carrying value of the Loan at December 31, 2013 approximated fair value. At December 31, 2014, there was no borrowing availability under the equipment line of credit.
	Software Financing—In May 2012, the Company entered into a $1.8 million agreement to finance the purchase of a perpetual software license and the related first year technical support (the “Software Finance Agreement”). The Software Finance Agreement was secured by the financed assets. In May 2013, the Company renewed the related technical support for a second year, increasing the financed amount by $0.6 million. In February 2014, the Company paid the outstanding balance under the Software Finance Agreement in full. As of December 31, 2014 and 2013, the outstanding balance under the Software Finance Agreement was zero and $0.9 million, respectively.

Noncontrolling_Interest

Noncontrolling Interest	12 Months Ended
	Dec. 31, 2014
Noncontrolling Interest [Abstract]
Noncontrolling Interest	11. NONCONTROLLING INTEREST
	On September 30, 2014, the Company signed an agreement to establish a joint venture, Demandware K.K., in Japan. As of December 31, 2014, the Company contributed approximately $2.5 million to the joint venture in cash in exchange for 75% of its outstanding shares of common stock, and another investor contributed $0.8 million to the joint venture in cash in exchange for the remaining 25% of its outstanding shares of common stock.
	All shares of the common stock held by the noncontrolling investor are callable by the Company or puttable by the noncontrolling investor upon certain contingent events such as a change of control or a deadlock. Should the call or put options be exercised, the redemption value would be determined based on a prescribed formula derived from i) the relative revenues of Demandware K.K. and the Company and ii) Demandware’s average market capitalization over a pre-defined period (“Formula Redemption Price”). Certain call or put options contingent upon a change of control may be settled at the Company’s discretion with Company stock or cash. During an exit period commencing on January 1, 2018 through January 1, 2020, all shares of the common stock held by the noncontrolling investor are callable by the Company or puttable by the noncontrolling investor. If the Company call option is exercised on or before July 1, 2018, the redemption value would be the greater of the Formula Redemption Price or three times the capital investment the noncontrolling investor has made in Demandware K.K. If the Company call option is exercised after July 1, 2018 or if the the noncontrolling investor put option is exercised at any time during the exit period, the redemption value would equal the Formula Redemption Price.
	The redeemable noncontrolling interests in Demandware K.K. is classified outside of permanent equity in the Company’s consolidated balance sheet as of December 31, 2014, primarily due to the put right available to the redeemable noncontrolling interest holders in the future which may be settled in cash or common stock of the Company. The balance of the redeemable noncontrolling interests is reported at the greater of the initial carrying amount adjusted for the redeemable noncontrolling interest’s share of earnings, or its estimated redemption value. The resulting changes in the estimated redemption amount (increases or decreases) are recorded with corresponding adjustments against additional paid-in capital. The estimated redemption value of the redeemable noncontrolling interests was not material at December 31, 2014.
	The changes in the redeemable noncontrolling interests classified as temporary equity in the balance sheet for the year ended December 31, 2014 are as follows (in thousands):
	Balance, December 31, 2013	$	—
	Contribution from noncontrolling interests		830
	Net loss attributable to noncontrolling interests		(7	)
	Balance, December 31, 2014	$	823

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	12. COMMITMENTS AND CONTINGENCIES
	Operating Leases—The Company has several operating leases for its office space that expire on various dates through 2023. Minimum rent payments under operating leases are recognized on a straight-line basis over the term of the lease including any periods of free rent and rent concessions. During the years ended December 31, 2014, 2013 and 2012, rent expense was $3.4 million, $2.6 million, and $2.1 million, respectively.
	The Company’s obligation for lease payments is as follows at December 31, 2014 (in thousands):
	Years Ending December 31
	2015	$	4,169
	2016		4,195
	2017		3,742
	2018		3,085
	2019		2,509
	Thereafter		1,241
	Total minimum lease payments	$	18,941
	Co-location Services—The Company has agreements with third parties to provide co-location services for hosting operations, which typically have a term of 24 months and expire by January 2016. The agreements require payment of a minimum amount per month for a fixed period of time in return for which the co-location service provider provides certain guarantees of network availability.
	The Company recorded co-location service expenses of $5.3 million, $3.2 million, and $2.5 million during the years ended December 31, 2014, 2013, and 2012, respectively. Future minimum payments as of December 31, 2014 under these arrangements are $4.4 million in 2015 and $1.7 million in 2016.
	Patent Infringement—The Company has received both direct claims from non-practicing entities claiming infringement of patents owned by them and indemnification requests from customers that have received letters from or been sued by such entities. Many of those underlying claims have not yet been resolved, and the extent, if any, of the Company’s indemnification obligations has not been determined. Certain of these matters include speculative claims for substantial or indeterminate amounts of damages. In addition, some of the patents at issue are the subject of pending legal proceedings between the patent owners and one or more leading digital commerce companies, and the outcome of those proceedings could affect the extent to which the patent owners seek to prosecute claims against the Company or its customers. The Company’s business could be materially adversely affected by any significant disputes between the Company and its customers as to intellectual property litigation to which the Company might become a party or for which the Company may be required to provide indemnification. Adverse results in these matters may include awards of substantial monetary damages, costly licensing agreements, or orders preventing the Company from offering certain features, functionalities, products, or services, and may also cause the Company to change its business practices, and require development of non-infringing products or technologies, which could result in a loss of revenues and otherwise harm the Company’s business. As of December 31, 2014, the Company has not made an accrual related to these matters.
	The Company records a liability when it believes that a loss is both probable and reasonably estimable. On a quarterly basis, the Company reviews each of its legal proceedings to determine whether it is probable, reasonably possible or remote that a liability has been incurred and, if it is at least reasonably possible, whether a range of loss can be reasonably estimated. Significant judgment is required to determine both the likelihood of there being a loss and the estimated amount of such loss. Until the final resolution of such matters, there may be an exposure to loss in excess of the amount recorded, and such amounts could be material. The Company expenses legal fees in the period in which they are incurred.
	In all of the Company’s outstanding legal matters for which it has not made an accrual, the Company is unable to estimate a range of reasonably possible loss due to various factors, including, among others, the early stage and uncertain outcome of the pending lawsuits to which the Company is not a party; and the significant factual issues to be resolved regarding the extent, if any, of the Company’s indemnification obligations. Given the significant uncertainties involved in these matters, the Company cannot predict the timing or extent of their impact, if any, on its business, consolidated financial position, results of operations or cash flows, which could be material, particularly in any fiscal quarter in which it may accrue a related liability.

Capitalization

Capitalization	12 Months Ended
	Dec. 31, 2014
Text Block [Abstract]
Capitalization	13. CAPITALIZATION
	As of December 31, 2014, the Company’s authorized stock consists of 240,000,000 shares of common stock, par value of $0.01 per share, and 10,000,000 shares of preferred stock, par value of $0.01 per share. No shares of preferred stock are issued or outstanding at December 31, 2014.
	On March 20, 2012, upon the closing of the IPO, all outstanding shares of redeemable convertible preferred stock were automatically converted into 18,028,763 shares of common stock.

Warrants

Warrants	12 Months Ended
	Dec. 31, 2014
Text Block [Abstract]
Warrants	14. WARRANTS
	In July 2008, in connection with the Company’s entry into the 2008 Loan Agreement (see Note 10), the Company issued a warrant to purchase shares of its Series C Preferred Stock, which, at the closing of the IPO, automatically converted into a warrant to purchase 23,092 shares of the Company’s common stock at an exercise price of $3.90 per share. The warrant was exercisable at any time through its expiration in July 2018. So long as the warrant remained outstanding and exercisable for redeemable convertible preferred stock, the warrant liability was recorded at fair value at each balance sheet date with any change in fair value included as a component of other (expense) income. At the time of conversion of the warrant upon the closing of the IPO, the fair value of the warrant was $0.5 million, which was reclassified as a component of additional paid-in capital. The warrant was net exercised in September 2012 resulting in the issuance of 20,186 shares of common stock. For the years ended December 31, 2012, the Company recognized $0.4 million of loss for the change in the fair value of the warrant.

StockBased_Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	15. STOCK-BASED COMPENSATION
	The following table presents stock-based compensation expense included in the Company’s consolidated statements of operations and comprehensive loss (in thousands):
		Year Ended December 31,
		2014			2013			2012
	Cost of subscription revenue	$	701		$	391		$	175
	Cost of service revenue		1,967			1,179			722
	Sales and marketing		7,474			4,296			1,842
	Research and development		7,513			3,574			1,509
	General and administrative		8,975			5,248			2,795
		$	26,630		$	14,688		$	7,043
	Stock-based compensation cost for the year ended December 31, 2014 includes $19.5 million related to restricted stock awards, $6.4 million related to stock options, $0.4 million related to the Company’s Employee Stock Purchase Plan (“ESPP”) and $0.3 million related to employee compensation contracts payable in cash or Company shares. Stock-based compensation cost for the year ended December 31, 2013 includes $8.4 million related to restricted stock awards, $6.1 million related to stock options and $0.2 million related to the ESPP. Stock-based compensation cost for the year ended December 31, 2012 includes $2.8 million related to restricted stock awards and $4.2 million related to stock options.
	As of December 31, 2014, the Company had two stock-based compensation plans, the 2004 Stock Option and Grant Plan (the “2004 Plan”), and the 2012 Stock Incentive Plan (the “2012 Plan”). The 2012 Plan provides for the grant of incentive stock options to the Company’s employees and the grant of non-statutory stock options, restricted stock, restricted stock units, stock appreciation rights, performance units and performance shares to the Company’s employees, directors and consultants. Upon the effectiveness of the 2012 Plan, the Company ceased granting awards under the 2004 Plan. However, the 2004 Plan will continue to govern the terms and conditions of the outstanding awards previously granted thereunder.
	Under the 2012 Plan, the Company may issue up to 8,126,768 shares of common stock pursuant to stock options and stock awards, which include shares of common stock reserved for issuance under the 2004 Plan that remained available for issuance immediately prior to the inception of the 2012 Plan. As of December 31, 2014, the Company has authorized 240,000,000 shares of common stock and 4,846,670 shares of common stock remain available under the 2012 Stock Incentive Plan.
	Stock Options—Under the 2012 Plan, stock options may be granted at an exercise price not less than the fair market value of the Company’s common stock on the date of grant. Substantially all stock options and restricted stock awards currently outstanding under both plans vest over a period of four years.
	The Company uses the Black-Scholes option-pricing model to estimate the fair value of stock options awards and determine the related compensation expense. The fair value of the stock options granted was calculated using the following key assumptions:
		Year Ended December 31,
		2014			2013			2012
	Risk-free interest rate		1.8	%		2.1	%		1.3	%
	Expected dividend yield		—			—			—
	Expected term (in years)		6			6			6
	Weighted average expected volatility		49.2	%		50.4	%		57	%
	The risk-free interest rate assumption was based on the U.S. Treasury zero-coupon bonds with maturities similar to those of the expected term of the award being valued. The assumed dividend yield was based on the Company’s expectation of not paying dividends in the foreseeable future. The weighted-average expected life for employee options reflects the application of the simplified method, which represents the average of the contractual term of the options and the weighted-average vesting period for all option tranches. The simplified method has been used since the Company does not have sufficient historical exercise data to provide a reasonable basis upon which to estimate the expected term due to a limited period of the Company’s life. The expected life of options granted to nonemployees is equal to the remaining contractual term as of the measurement date. The Company bases the majority of its estimate of expected volatility using volatility data from comparable public companies in similar industries and markets because there is currently limited public market history for the Company’s common stock, and therefore, a lack of market-based company-specific historical and implied volatility information.
	The summary of stock option activity for the year ended December 31, 2014 is as follows (in thousands, except per share and term information):
		Shares			Weighted-			Weighted-			Aggregate
					Average			Average			Intrinsic
					Exercise			Remaining			Value
					Price			Contractual
								Life (in
								Years)
	Outstanding—January 1, 2014		2,994		$	12.39
	Granted		194			64.31
	Forfeited		(28	)		30.34
	Expired or cancelled		(2	)		12.49
	Exercised		(572	)		11.97
	Outstanding—December 31, 2014		2,586		$	16.18			6.25		$	108,329
	Exercisable—December 31, 2014		1,928		$	7.91			5.63		$	95,709
	Options vested and expected to vest— December 31, 2014		2,553		$	15.8			6.22		$	107,849
	The following table summarizes information relating to stock options granted and exercised (in thousands, except per share data):
		Year Ended December 31,
		2014			2013			2012
	Weighted average grant date fair value per share	$	31.79		$	16.87		$	16.49
	Aggregate intrinsic value of options exercised		29,363			42,099			21,402
	Cash proceeds received upon exercise of options		6,848			7,948			1,282
	The aggregate intrinsic value represents the difference between the estimated fair value at exercise and the exercise price paid by the employee. The amount of aggregate intrinsic value will change based on the fair market value of the common stock.
	As of December 31, 2014, total compensation cost not yet recognized related to stock option awards was $11.7 million, which is expected to be recognized over a weighted-average period of 2.3 years.
	Restricted Stock Awards—The Company’s restricted stock awards generally vest over a two- or four-year period and upon vesting, the restrictions on the shares are released. In December 2013, the Company granted a 25,000 share performance-based restricted stock award, and the restriction on the shares will be released when the recipient achieves operational metrics as defined in the agreement. In December 2014, the operating metrics were achieved and the entire 25,000 shares of performance-based restricted stock were vested.
	The summary of restricted stock awards activity is as follows (in thousands, except per share data):
		Number of			Weighted-
		Shares			Average
					Grant Date
					Fair Value
	Nonvested at December 31, 2013		961		$	32.51
	Granted		686			66.18
	Vested		(414	)		32.42
	Forfeited		(39	)		46.98
	Nonvested at December 31, 2014		1,194		$	51.4
	The following table summarizes information relating to restricted stock granted and vested (in thousands, except per share data):
		Year Ended December 31,
		2014			2013			2012
	Weighted average grant date fair value per share	$	66.18		$	33.13		$	30.92
	Total fair value of restricted stock vested		25,801			6,418			2,350
	Total compensation cost not yet recognized related to restricted stock awards was $50.4 million, which is expected to be recognized over a weighted-average period of 2.9 years.
	Employee Stock Purchase Plan—The ESPP and its foreign corollaries permit eligible employees to purchase up to a maximum of 400,000 shares of our common stock through accumulated payroll deductions. Each offering is a six month period (a “Plan Period”), and the purchase price of the stock is equal to 85% of the lesser of the market value of such shares at the first or last business day of a Plan Period. Individual employee contributions to the ESPP may not exceed $12,500 in each Plan Period. During the 2014 and 2013 Plan Periods, employee contributions were accumulated to purchase 27,088 and 14,934 shares, respectively, at weighted average prices per share of $51.34 and $36.47, respectively. No share was purchased under the ESPP for the year ended December 31, 2012. The fair value of the ESPP shares purchased is estimated on the Plan Period commencement date using a Black-Scholes pricing model with the expense recognized over the expected life, which is the six month offering period. The weighted average fair value per share of ESPP shares purchased during the year ended December 31, 2014 and 2013 was $16.43 and $9.62, respectively. At December 31, 2014, 357,978 shares remain available for future issuance under the ESPP.
	Employee Compensation Contracts Payable in Cash or Shares—As part of the CQuotient acquisition, the Company agreed to pay certain selling shareholders total additional consideration of $3.4 million contingent upon their continued employment with the Company for a specified period of time. These contingent payments are payable in cash or shares of the Company’s common stock at the option of the Company (see Note 4). The Company recognized the contingent payments over the respective required period of employment. During the year ended December 31, 2014, the Company recorded $0.3 million of compensation expense related to these contingent payments. No such expense was recorded during the years ended December 31, 2013 and 2012.
Restricted Stock Units—On June 6, 2014, the Company granted restricted stock units for 16,875 shares of common stock to the Company’s former Chief Financial Officer with a grant date fair value of $60.08 per share, as outlined in the Transition and Separation Letter Agreement dated February 10, 2014 between the Company and the former Chief Financial Officer (the “Transition and Separation Letter Agreement”). The restricted stock units will be paid out in shares one year from the grant date, provided that the former Chief Financial Officer substantially complies with the Post-Employment Assistance undertakings and with the Restrictive Covenants Agreements, each as defined in the Transition and Separation Letter Agreement. If the former Chief Financial Officer does not substantially comply, the restricted stock units will be forfeited as of the date of noncompliance. These restricted stock units granted to the former Chief Financial Officer are remeasured at fair value at each reporting date until the award vests. During the year ended December 31, 2014, the Company recorded $0.6 million of consulting expense for this restricted stock unit award, and no such expense was recorded during the year ended December 31, 2013.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income Taxes	16. INCOME TAXES
	The provision for income taxes for the years ended December 31, 2014, 2013 and 2012 consists of the following (in thousands):
		December 31,
		2014			2013			2012
	Loss before income taxes:
	Domestic	$	(31,431	)	$	(19,062	)	$	(5,050	)
	International		2,321			1,634			1,129
		$	(29,110	)	$	(17,428	)	$	(3,901	)
		December 31,
		2014			2013			2012
	Current income tax provision:
	Federal	$	—		$	—		$	—
	State		72			52			56
	Foreign		776			457			368
	Total current income tax provision		848			509			424
	Deferred income tax (benefit) provision:
	Federal		(2,795	)		—			—
	State		(3	)		—			—
	Foreign		(100	)		65			(3	)
	Total deferred income tax (benefit) provision		(2,898	)		65			(3	)
	Total income tax (benefit) provision	$	(2,050	)	$	574		$	421
	The 2014 income tax benefit includes the release of $3.0 million of valuation allowance that resulted from the recognition of the deferred tax liabilities in the CQuotient acquisition, which provided evidence to support the recoverability of the deferred tax asset totaling $3.0 million.
	The differences in total provision for income taxes that would result from applying the 34% federal statutory rate to (loss) income before provision for income taxes and the reported provision for income taxes are as follows:
		Years Ended December 31,
		2014			2013			2012
					(As revised)			(As revised)
	U.S. Federal tax expense at statutory rates		34	%		34	%		34	%
	State income taxes, net of federal tax benefit		2	%		0.5	%		(1	)%
	Foreign rate differential		1	%		0.5	%		1	%
	Permanent differences		6	%		(4	)%		(5	)%
	Stock-based compensation		(6	)%		(3	)%		(6	)%
	Uncertain tax provisions		(1	)%		(1	)%		(2	)%
	Valuation allowance		(29	)%		(30	)%		(32	)%
			7	%		(3	)%		(11	)%
	Components of the net deferred tax assets as of December 31, 2014 and 2013 are as follows (in thousands):
		December 31,
		2014			2013
					(As revised)
	Operating loss carryforwards	$	17,804		$	12,948
	Capitalized research and development costs		4,226			8,433
	Accrued expenses		7,411			5,630
	Research and development credits		3,738			1,160
	Deferred revenue		1,578			(311	)
	Stock compensation		5,367			2,850
	Depreciation		167			296
	Other		24			3
	Total deferred tax assets		40,315			31,009
	Valuation allowance for deferred tax assets		(40,493	)		(31,074	)
	Net deferred tax liability	$	(178	)	$	(65	)
	The Company has historically incurred operating losses, and given the cumulative losses and limited history of profits, the Company has recorded a full valuation allowance against its deferred tax assets for all periods to date with the exception of the deferred tax asset related to Demandware E-Commerce (Shanghai) Limited, Demandware UK Limited, and Demandware Australia Pty Limited.
	In general, it is the practice and intention of the Company to reinvest the earnings of its non-U.S. subsidiaries in those operations. As of December 31, 2014, the Company has not made a provision for U.S. or additional foreign withholding taxes of the excess of the amount for financial reporting over the tax basis of investments in foreign subsidiaries that are essentially permanent in duration. Generally, such amounts become subject to U.S. taxation upon the remittance of dividends and under certain other circumstances. It is not practicable to estimate the amount of deferred tax liability related to investments in these foreign subsidiaries.
	During the year ended December 31, 2014, the valuation allowance increased by $9.4 million due to the increase in deferred tax asset associated with the research and development costs and accrued expenses and the full valuation allowance against that asset. During the year ended December 31, 2013, the valuation allowance increased by $5.2 million due to the increase in deferred tax asset associated with the net operating loss and the full valuation allowance against that asset.
	At December 31, 2014, the Company had federal and state net operating loss carryforwards of approximately $138.8 million and $69.6 million, respectively. At December 31, 2014, the Company also had federal and state research and development tax credit carryforwards of $5.0 million and $3.3 million, respectively. The net operating loss carryforwards and tax credits expire at various dates through 2034. Because of the change of ownership provisions of the Tax Reform Act of 1986, use of a portion of the Company’s domestic NOL and tax credit carryforwards may be limited in future periods. Further, a portion of the carryforwards may expire before being applied to reduce future income tax liabilities.
	As a result of certain realization requirements of share-based payment accounting guidance, the table of deferred tax assets and liabilities shown above does not include certain deferred tax assets as of December 31, 2014 and 2013 that arose directly from tax deductions related to equity compensation in excess of compensation recognized for financial reporting. Equity will be increased by $35.5 million if and when such deferred tax assets are ultimately realized. The Company uses ASC 740 ordering when determining when excess tax benefits have been realized.
	The following table indicates the changes to the Company’s unrecognized tax benefits for the years ended December 31 (in thousands):
		2014			2013			2012
	Beginning balance	$	1,418		$	1,061		$	805
	Decrease related to current tax year		(409	)		—			—
	Increase related to current tax year		497			357			256
	Ending balance	$	1,506		$	1,418		$	1,061
	The liability for unrecognized tax benefits includes no accrued interest and penalties. The Company expects none of the unrecognized tax benefits will decrease within the next 12 months related to expired statutes or settlement with the taxing authorities. Under the Company’s accounting policies, the unrecognized tax benefits disclosed above are presented in the financial statements as a reduction to a deferred tax asset.
	The Company files federal, state, and foreign income tax returns in jurisdictions with varying statutes of limitations. With few exceptions, all tax years 2004 through 2014 remain subject to examination by federal and most state tax authorities due to the Company’s net operating loss carryforwards. In the Company’s foreign jurisdictions, all tax years remain subject to examination.

Employee_Benefits

Employee Benefits	12 Months Ended
	Dec. 31, 2014
Postemployment Benefits [Abstract]
Employee Benefits	17. EMPLOYEE BENEFITS
	The Company has a 401(k) defined contribution plan (the “401(k) Plan”) for employees. The 401(k) Plan includes substantially all United States full-time employees. Under the terms of the plan, participants may contribute up to the lower of 20% of their salary or the statutorily prescribed limit to the plan. At the election of its Board of Directors, the Company may make matching employee contributions, though it has not done so to date.

Selected_Quarterly_Information

Selected Quarterly Information	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Information	18. SELECTED QUARTERLY INFORMATION (UNAUDITED)
	For reasons discussed in greater detail within “Correction of Immaterial Errors” in Note 1, Organization and Basis of Presentation, the Company has revised its previously issued consolidated financial statements contained in the quarterly periods ended March 31, 2014, June 30, 2014, September 30, 2014 and each of the quarterly periods in the year ended December 31, 2013. The revisions resulted from a correction of immaterial errors due to the change in the Company’s revenue recognition policy for implementation services.
	The following tables summarize the effects of the revisions on our previously issued unaudited condensed consolidated financial statements:
		2014
		1st Quarter								2nd Quarter								3rd Quarter								4th
																										Quarter
		As Previously			Adjustment		As Revised			As Previously			Adjustment		As Revised			As Previously			Adjustment		As Revised
		Reported								Reported								Reported
		(in thousands, except per share amounts)
	Revenue	$	32,178		$	396	$	32,574		$	36,085		$	661	$	36,746		$	38,227		$	504	$	38,731		$	52,502
	Gross profit		23,270			396		23,666			26,080			661		26,741			27,442			504		27,946			40,152
	Loss from operations		(8,496	)		396		(8,100	)		(9,025	)		661		(8,364	)		(5,651	)		504		(5,147	)		(6,181	)
	Loss before provision for income taxes		(8,494	)		396		(8,098	)		(8,958	)		661		(8,297	)		(6,654	)		504		(6,150	)		(6,565	)
	Net loss		(8,759	)		396		(8,363	)		(9,185	)		661		(8,524	)		(6,853	)		504		(6,349	)		(3,824	)
	Net loss attributable to noncontrolling interest		—			—		—			—			—		—			—			—		—			7
	Net loss attributable to Demandware		(8,759	)		396		(8,363	)		(9,185	)		661		(8,524	)		(6,853	)		504		(6,349	)		(3,817	)
	Basic net loss per share attributable to Demandware	$	(0.25	)	$	0.01	$	(0.24	)	$	(0.27	)	$	0.02	$	(0.25	)	$	(0.20	)	$	0.02	$	(0.18	)	$	(0.11	)
	Diluted net loss per share attributable to Demandware	$	(0.25	)	$	0.01	$	(0.24	)	$	(0.27	)	$	0.02	$	(0.25	)	$	(0.20	)	$	0.02	$	(0.18	)	$	(0.11	)
		2013
		1st Quarter								2nd Quarter								3rd Quarter								4th Quarter
		As			Adjustment		As			As			Adjustment		As			As			Adjustment		As			As			Adjustment		As
		Previously					Revised			Previously					Revised			Previously					Revised			Previously					Revised
		Reported								Reported								Reported								Reported
		(in thousands, except per share amounts)
	Revenue	$	20,514		$	290	$	20,804		$	23,207		$	342	$	23,549		$	24,479		$	1,162	$	25,641		$	35,536		$	1,084	$	36,620
	Gross profit		14,032			290		14,322			16,665			342		17,007			17,428			1,162		18,590			27,594			1,084		28,678
	(Loss) income from operations		(7,317	)		290		(7,027	)		(8,413	)		342		(8,071	)		(6,769	)		1,162		(5,607	)		1,710			1,084		2,794
	(Loss) income before provision for income taxes		(7,753	)		290		(7,463	)		(8,310	)		342		(7,968	)		(6,147	)		1,162		(4,985	)		1,904			1,084		2,988
	Net (loss) income		(7,972	)		290		(7,682	)		(8,455	)		342		(8,113	)		(6,257	)		1,162		(5,095	)		1,804			1,084		2,888
	Basic net (loss) income per share attributable to Demandware	$	(0.27	)	$	0.01	$	(0.26	)	$	(0.28	)	$	0.01	$	(0.27	)	$	(0.20	)	$	0.03	$	(0.17	)	$	0.06		$	0.03	$	0.09
	Diluted net (loss) income per share attributable to Demandware	$	(0.27	)	$	0.01	$	(0.26	)	$	(0.28	)	$	0.01	$	(0.27	)	$	(0.20	)	$	0.03	$	(0.17	)	$	0.05		$	0.03	$	0.08

Subsequent_Events

Subsequent Events	12 Months Ended
	Dec. 31, 2014
Subsequent Events [Abstract]
Subsequent Events	19. SUBSEQUENT EVENTS
	Tomax Acquisition—On January 12, 2015, the Company acquired 100% of the equity of Tomax Corporation (“Tomax”), an enterprise software company that provides an integrated solution for retail point of sale and store operations, for total cash consideration of approximately $60 million, of which $12 million was held in escrow to secure certain indemnification and other obligations of the sellers. An additional consideration of up to $15 million, payable in cash or shares of the Company’s common stock at the option of the Company, is payable to the Tomax equityholders in 1.5 to 2 years contingent upon the continued post-closing employment of certain key employees of Tomax. This consideration will be recognized in the Company’s post-combination financial statements as compensation expense over the employment period. The initial purchase accounting of the business combination is incomplete as of the issuance date of these financial statements. Therefore, the Company is unable to disclose the fair value of the equity interest in Tomax immediately before the acquisition date, the valuation techniques and related inputs used to measure the acquisition date fair value and the pro forma financial information. During fiscal year ended December 31, 2014, $0.9 million of acquisition-related costs were incurred to effect the Tomax acquisition, which is included in the Company’s general and administrative expense.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates—The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America (“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 revenue, cost of revenue, and expenses during the reporting period. Actual results could differ from those estimates.
Foreign Currency Translation	Foreign Currency Translation—The functional currency of the Company’s foreign subsidiaries is the local currency. All assets and liabilities denominated in a foreign currency are translated into U.S. dollars at the exchange rate on the balance sheet date. Revenue and expenses are translated at the average exchange rate during the period. Translation gains or losses are included as a component of accumulated other comprehensive (loss) income in stockholders’ equity (deficit). Transaction gains or losses that arise from exchange rate fluctuations on transactions denominated in a currency other than the functional currency are included in other income (expense) in the accompanying consolidated results of operations as incurred. For the years ended December 31, 2014, 2013 and 2012, foreign currency transaction (losses) gains of ($1.7) million, $0.6 million, and $0.1 million, respectively, are included in other expenses in the accompanying consolidated statements of operations and comprehensive loss.
Business Combination	Business Combination—The Company allocates the purchase price to the assets acquired and the liabilities assumed at their estimated fair values as of the date of the acquisition with any excess of the purchase price paid over the estimated fair value of net assets acquired recorded as goodwill. The fair value of the assets acquired and liabilities assumed is typically determined by using either estimates of replacement costs or multiple period excess earnings methods. Contingent payments that are dependent upon post-combination services, if any, are considered separate transactions outside of the business combination and therefore included in the post-combination operating results. Transaction costs in connection with the acquisition are recorded as operating expenses.
Cash Equivalents and Short-Term Investments	Cash Equivalents and Short-Term Investments—The Company considers all highly liquid investments maturing within 90 days from the date of purchase to be the equivalent of cash for the purpose of balance sheet and statement of cash flows presentation. As of December 31, 2014, $140.1 million of the Company’s cash equivalents were invested in money market funds, and $2.5 million in marketable securities. As of December 31, 2013, $226.1 million of the Company’s cash equivalents were invested in money market funds, and $3.0 million in marketable securities.
	Short-term investments in marketable securities are classified as available-for-sale and mature within 12 months from the date of purchase. The Company’s investments in marketable securities are recorded at fair value, with any unrealized gains and losses, net of taxes, reported as a component of stockholders’ equity until realized or until a determination is made that an other-than-temporary decline in market value has occurred. When the Company determines that an other-than-temporary decline has occurred for debt securities that the Company does not then intend to sell, the Company recognizes the credit loss component of an other-than-temporary impairment in other income (expense) and the remaining portion in other comprehensive loss. The credit loss component is identified as the amount of the present value of cash flows not expected to be received over the remaining term of the security, based on cash flow projections. In determining whether an other-than-temporary impairment exists, the Company considers: (i) the length of time and the extent to which the fair value has been less than cost; (ii) the financial condition and near-term prospects of the issuer of the securities; and (iii) the Company’s intent and ability to retain the security for a period of time sufficient to allow for any anticipated recovery in fair value. The cost of marketable securities sold is determined based on the specific identification method and any realized gains or losses on the sale of investments are reflected as a component of interest income or expense.
Accounts Receivable	Accounts Receivable—Accounts receivable represent trade receivables from customers when the Company has invoiced for software subscriptions and/or services and it has not yet received payment. The Company maintains an allowance for doubtful accounts for the estimated probable losses on uncollectible accounts receivable, and presents accounts receivable net of this allowance. The allowance is based upon a number of factors including the credit worthiness of customers, the Company’s historical experience with customers, the age of the receivable and current market and economic conditions. Such factors are reviewed and updated by the Company on a quarterly basis. Account balances are written off against the allowance after all means of collection have been exhausted and the potential for recovery is considered remote.
	Activity within the allowance for doubtful accounts is as follows, (in thousands):
		Years Ended December 31,
		2014			2013			2012
	Balance at beginning of year	$	459		$	—		$	—
	Charges		671			497			—
	Write-offs		(605	)		(38	)		—
	Balance at end of year	$	525		$	459		$	—
Derivative Instruments	Derivative Instruments—The Company is exposed to foreign currency exchange rate risk relating to its ongoing business operations. Forward contracts on various foreign currencies are entered into to manage the foreign currency exchange rate risk and are intended to offset economic exposures of the Company. The Company does not use derivative financial instruments for trading or speculative purposes. The Company does not designate these forward contracts as hedging instruments and these contracts are carried at fair value with changes in value recorded in operations. Cash flows from these forward contracts are reported in the consolidated statement of cash flows under cash flows from operating activities. See Note 6 for further discussion.
Concentrations of Credit Risk and Significant Customers	Concentrations of Credit Risk and Significant Customers—Financial instruments that potentially expose the Company to concentrations of credit risk include cash, cash equivalents, marketable securities, foreign currency forward contracts and accounts receivable. The Company maintains substantially all of its cash, cash equivalents, marketable securities and foreign currency forward contracts with financial institutions that management believes have high credit standings. To manage credit risk related to accounts receivable, the Company evaluates the allowances for potential credit losses. To date, losses resulting from uncollected receivables have not exceeded management’s expectations.
	As of December 31, 2014, no single customer comprised more than 10% of accounts receivable. As of December 31, 2013, the Company had one reseller representing 12% of accounts receivable. During the years ended December 31, 2014, 2013, and 2012, no single customer comprised more than 10% of the Company’s revenue.
Property and Equipment	Property and Equipment—Property and equipment are recorded at cost and depreciated using the straight-line method over the estimated useful lives of the related assets, which ranges from three to five years. Leasehold improvements are amortized over the lesser of the term of the lease or the useful life of the asset. When assets are retired or disposed of, the assets and related accumulated depreciation are eliminated from the accounts and any resulting gain or loss is included in the determination of net income or loss. Maintenance and repair expenditures are charged to expense as incurred.
Research and Development and Internal Use Software	Research and Development and Internal Use Software—Research and development expenses consist primarily of personnel and related expenses for the Company’s research and development staff, including salaries, benefits, bonuses and stock-based compensation and the cost of certain third party contractor costs. Expenditures for research and development, other than internal use software costs, are expensed as incurred.
	Software development costs associated with internal use software are capitalized when the preliminary project stage is completed, management has decided to make the project a part of its future offering, and the software will be used to perform the function intended. These capitalized costs include external direct costs of services consumed in developing or obtaining internal-use software, personnel and related expenses for employees who are directly associated with and who devote time to internal-use software projects. Capitalization of these costs cease once the project is substantially complete and the software is ready for its intended purpose. Post-configuration training and maintenance costs are expensed as incurred. Capitalized internal use software costs are amortized to cost of revenue using a straight-line method over its estimated useful life of four years, commencing when the software is ready for its intended use.
	During the years ended December 31, 2014 and 2013, no internal use software development cost was capitalized. During the year ended December 31, 2012, $0.2 million of internal use software development cost was capitalized. Capitalized internal use software is included in property and equipment.
	Amortization expense related to internal use software totaled $0.2 million, $0.2 million and $0.1 during the years ended December 31, 2014, 2013 and 2012, respectively. The net book value of capitalized internal use software at December 31, 2014 and 2013 was $0.4 million and $0.6 million, respectively.
Segment and Geographic Information	Segment and Geographic Information—Operating segments are defined as components of an enterprise for which discrete financial information is available that is evaluated on a regular basis by the chief operating decision maker, or decision making group, in deciding how to allocate resources and assess performance. The Company’s chief operating decision maker (“CODM”) is the Chief Executive Officer. The CODM reviews consolidated operating results to make decisions about allocating resources and assessing performance for the entire Company. The CODM views the Company’s operations and manages its business as one operating segment.
	Information about the Company’s operations in different geographic regions is presented in the tables below (in thousands):
		Year Ended December 31,
		2014			2013			2012
					(As revised)			(As revised)
	Revenue:
	United States	$	99,085		$	63,155		$	47,147
	Germany		22,218			16,521			20,578
	United Kingdom		18,328			13,130			9,100
	All other international		20,922			13,808			6,452
	Total revenue	$	160,553		$	106,614		$	83,277
	Long-lived assets (at year end):
	United States		23,214			8,814			7,976
	Germany		455			362			303
	United Kingdom		429			554			15
	All other international		196			60			83
	Total long-lived assets	$	24,294		$	9,790		$	8,377
Goodwill and Other Intangible Assets	Goodwill and Purchased Intangible Assets—Goodwill represents the excess of the purchase price in a business combination over the fair value of net tangible and intangible assets acquired. Goodwill is reviewed for impairment at least annually or whenever events or changes in circumstances indicate that the carrying value of the goodwill may not be recoverable. The Company’s annual impairment assessment date is November 30 of each fiscal year. The Company has determined that there is a single reporting unit for the purpose of goodwill impairment tests. The Company utilizes the two-step impairment test when testing goodwill for impairment. Under the first step of this test, the Company compares the fair value of the entity to its carrying value. If the carrying value exceeds the fair value, the Company conducts the second step of this test, in which the implied fair value of the goodwill is compared to its carrying amount. If the carrying amount of goodwill exceeds its implied fair value, an impairment loss would be recognized for the amount of the excess. During the year ended December 31, 2014, no potential impairment was identified under the first step of the test as the fair value of the entity was in excess of its carrying value. There was no goodwill at December 31, 2013.
	Purchased intangible assets represent those acquired from business combinations and are deemed to have a definite life. They are amortized over their useful lives, generally ranging from three to five years. The Company evaluates intangible assets for impairment whenever events or changes in circumstances indicate the carrying value of an asset or asset group may not be recoverable. During the year ended December 31, 2014, no such impairment indicator was identified. There were no purchased intangible assets at December 31, 2013.
Revenue Recognition	Revenue Recognition—The Company generates revenue from sales of its digital commerce solutions that leverage its proprietary technology, which are represented by subscription fees for its ecommerce, order management and predictive intelligence solutions, activation fees and related professional services. Professional services include implementation services, consulting services to support its customers once they are live on the Company’s solution and training.
	The Company recognizes revenue when persuasive evidence of an arrangement exists, delivery to customers has occurred or services have been rendered, the fee is fixed or determinable, and collectability is reasonably assured. The Company does not recognize revenue in excess of the amounts for which it has the right to invoice in an annual subscription year.
	In most instances, revenue from new customer acquisition is generated under sales agreements with multiple elements, comprised of subscription fees, related activation fees that allow customers to access the solutions, and professional services. The Company evaluates each element in a multiple-element arrangement to determine whether it represents a separate unit of accounting. An element constitutes a separate unit of accounting when the delivered item has standalone value and delivery of the undelivered element is probable and within the Company’s control. Subscriptions have standalone value because they are routinely sold separately by the Company.
	Other than the Company’s site readiness assessment offering, the Company’s professional services have standalone value because the Company has sold professional services separately or there are third party vendors that routinely provide similar professional services to its customers on a standalone basis. The Company does not have evidence of standalone value for site readiness assessments because they are not sold on a standalone basis and can only be provided by the Company.
	Activation fees provide access to the Company’s digital environment through production launch and are billed during the implementation phase and recorded as deferred revenue until a customer’s subscription period has commenced. Activation fees do not have standalone value because they are only sold in conjunction with a subscription to our ecommerce solutions, they are only sold by the Company, a customer could not resell it, and they do not represent the culmination of a separate earnings process.
	The Company allocates revenue to each element in an arrangement based on a selling price hierarchy. The selling price for a deliverable is based on its vendor-specific objective evidence (“VSOE”), if available, third party evidence (“TPE”), if VSOE is not available, or best estimated selling price (“BESP”), if neither VSOE nor TPE is available. As the Company has been unable to establish VSOE or TPE for the elements of its arrangements, the Company establishes the BESP for each element primarily by considering the weighted average of actual sales prices of professional services sold on a standalone basis and subscriptions including various add-on modules when sold together without professional services, and other factors such as gross margin objectives, pricing practices and growth strategy.
	Subscriptions include fees derived from contractually committed minimum levels of gross revenue processed by ecommerce customers on the Company’s cloud digital commerce platform, and fees derived from such customers’ gross revenue processed above the minimum contracted levels. Customers do not have the contractual right to take possession of the Company’s cloud software. The consideration allocated to the subscription for the aggregate minimum subscription fee is recognized on a straight-line basis over the subscription term once a customer’s subscription period has commenced. Should an ecommerce customer exceed the specified minimum levels of gross revenue processed, fees for customer gross revenue processed in excess of the committed minimum level are billed for the excess volume. The Company recognizes revenue from the fees it receives for its customers’ gross revenue processed in excess of the committed minimum level in the period in which such gross revenue is processed and earned.
	Activation fees and site readiness assessments without standalone value are recognized ratably over the longer of the life of the agreement or the expected customer life, which is currently estimated to be just over six years. The Company evaluates the length of the amortization period based on our experience with customer contract renewals and consideration of the period over which those customers will benefit from the related offerings.
	The consideration allocated to professional services with standalone value is recognized as revenue using the proportional performance method.
	Deferred revenue primarily consists of the unearned portion of billed subscription and services fees. Once a customer’s subscription period has commenced, the Company typically invoices customers on a monthly or quarterly basis. In addition, the Company often invoices the first year subscription fee in advance upon customer contract execution as an initiation payment. Initiation payments are included in deferred revenue upon payment.
	Reimbursable costs received for out-of-pocket expenses are recorded as revenue and cost of revenue in the consolidated statements of operations and comprehensive loss. Sales taxes collected from customers and remitted to government authorities are excluded from revenue.
	Cost of Revenue—Cost of subscription revenue primarily consists of hosting costs, data communications expenses, depreciation expenses associated with computer equipment, personnel and related costs, including salaries, bonuses, payroll taxes, recruiting fees and stock compensation, software license fees and amortization expenses associated with capitalized software. In addition, the Company allocates a portion of overhead, such as rent, IT costs, depreciation and amortization and employee benefits costs, to cost of revenue based on headcount.
	Cost of services revenue primarily consists of personnel and related costs, third party contractors and allocated overhead. The Company’s cost of services revenue is expensed as the costs are incurred.
Cost of Revenue	Cost of Revenue—Cost of subscription revenue primarily consists of hosting costs, data communications expenses, depreciation expenses associated with computer equipment, personnel and related costs, including salaries, bonuses, payroll taxes, recruiting fees and stock compensation, software license fees and amortization expenses associated with capitalized software. In addition, the Company allocates a portion of overhead, such as rent, IT costs, depreciation and amortization and employee benefits costs, to cost of revenue based on headcount.
	Cost of services revenue primarily consists of personnel and related costs, third party contractors and allocated overhead. The Company’s cost of services revenue is expensed as the costs are incurred.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets—The Company considers whether indicators of impairment of its long-lived assets are present. If such indicators are present, the Company determines whether the sum of the estimated undiscounted future cash flows attributable to such assets is less than their carrying amount, and if so, the Company recognizes an impairment loss based on the excess of the carrying amount of the assets over their fair value. To date, no such impairment has occurred.
Advertising	Advertising—Advertising costs are charged to operations as incurred and include direct marketing, events, public relations, sales collateral materials and partner programs. Advertising expense was approximately $8.4 million, $6.2 million and $4.0 million for the years ended December 31, 2014, 2013 and 2012, respectively.
Income Taxes	Income Taxes—Deferred tax assets and liabilities are recognized based on temporary differences between the financial reporting and income tax bases of assets and liabilities using rates anticipated to be in effect when such temporary differences reverse. A valuation allowance against deferred tax assets is recorded, based upon the available evidence, if it is more likely than not that some or all of the deferred tax assets will not be realized. The Company assesses its income tax positions and records tax benefits based upon management’s evaluation of the facts, circumstances, and information available at the reporting date. For those tax positions where it is more likely than not that a tax benefit will be sustained, the Company records the largest amount of tax benefit with a greater than 50 percent likelihood of being realized upon ultimate settlement with a taxing authority having full knowledge of all relevant information. For those income tax positions where it is not more likely than not that a tax benefit will be sustained, no tax benefit is recognized in the financial statements. The unrecognized tax benefits are currently presented as a reduction to the deferred tax assets in the financial statements, unless the uncertainty is expected to be resolved within one year. Potential interest and penalties associated with such uncertain tax positions are recorded as a component of income tax expense.
Stock-Based Compensation	Stock-Based Compensation—The Company accounts for all stock options granted to employees and nonemployees using a fair value method. The Black-Scholes option pricing model is used to determine the fair value of the award, which is then recognized on a straight-line basis over the requisite services period, which is the vesting period of the award. The measurement date for employee awards is the date of the grant, and the measurement date for nonemployee awards is the date the performance or services are completed.
Other Comprehensive (Loss) Income	Other Comprehensive (Loss) Income—Other comprehensive (loss) income consists of foreign currency translation adjustments and unrealized gains or losses on marketable securities.
Warranties	Warranties—The Company includes service level commitments to its customers warranting certain levels of uptime reliability and performance and permitting those customers to receive credits in the event that the Company fails to meet those levels. To date, the Company has not incurred any material costs as a result of such commitments.
Commissions	Commissions—The Company recognizes commission expense related to subscriptions in the period in which the contract is signed.
Recent Accounting Pronouncements	Recent Accounting Pronouncements—
	In May 2014, the Financial Accounting Standards Board issued Accounting Standards Update (“ASU”) No. 2014-09, “Revenue from Contracts with Customers”. The comprehensive new standard will supersede existing revenue recognition guidance and require revenue to be recognized when promised goods or services are transferred to customers in amounts that reflect the consideration to which the Company expects to be entitled in exchange for those goods or services. The guidance will also require that certain contract costs incurred to obtain or fulfill a contract, such as sales commissions, be capitalized as an asset and amortized as revenue is recognized. Adoption of the new rules could affect the timing of both revenue recognition and the recognition of contract costs for certain transactions. The guidance permits two implementation approaches, one requiring retrospective application of the new standard with restatement of prior years and one requiring prospective application of the new standard with disclosure of results under old standards. For the Company, the new standard will be effective January 1, 2017. The Company is currently evaluating the impact of adoption and the implementation approach to be used.

Organization_and_Basis_of_Pres1

Organization and Basis of Presentation (Tables)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Previously Reported and Adjusted Consolidated Statements of Operations and Comprehensive Loss	The following table presents the impact of these corrections on its consolidated statements of operations and comprehensive loss for the years ended December 31, 2013 and 2012 (in thousands, except per share data):
		For the Year Ended December 31, 2013									For the Year Ended December 31, 2012
		As Previously			Adjustment			As Revised			As Previously			Adjustment		As Revised
		Reported									Reported
	Revenue:
	Services	$	8,003		$	2,878		$	10,881		$	11,545		$	3,802	$	15,347
	Total revenue		103,736			2,878			106,614			79,475			3,802		83,277
	Gross profit		75,719			2,878			78,597			55,134			3,802		58,936
	Net loss	$	(20,880	)	$	2,878		$	(18,002	)	$	(8,124	)	$	3,802	$	(4,322	)
	Net loss attributable to common stockholders	$	(20,880	)	$	2,878		$	(18,002	)	$	(9,296	)	$	3,802	$	(5,494	)
	Net loss per share attributable to common stockholders, basic and diluted	$	(0.68	)	$	0.1		$	(0.58	)	$	(0.39	)	$	0.16	$	(0.23	)
	Comprehensive loss	$	(20,799	)	$	2,878		$	(17,921	)	$	(8,088	)	$	3,802	$	(4,286	)
Previously Reported and Adjusted Consolidated Balance Sheet	The following table presents the impact of these corrections on its consolidated balance sheet items as of December 31, 2013 (in thousands):
		For the Year Ended December 31, 2013
		As  Previously			Adjustment			As Revised
		Reported
	Current liabilities:
	Deferred revenue	$	19,609		$	(1,329	)	$	18,280
	Total current liabilities	$	43,056		$	(1,329	)	$	41,727
	Long-term liabilities:
	Deferred revenue	$	18,862		$	(10,754	)	$	8,108
	Total liabilities:	$	64,326		$	(12,083	)	$	52,243
	Stockholders’ equity:
	Accumulated deficit	$	(97,568	)	$	12,083		$	(85,485	)
	Total stockholders’ equity:	$	259,605		$	12,083		$	271,688
	Total liabilities and stockholders’ equity:	$	323,931		$	—		$	323,931

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Allowance for Doubtful Accounts Receivable	Activity within the allowance for doubtful accounts is as follows, (in thousands):
		Years Ended December 31,
		2014			2013			2012
	Balance at beginning of year	$	459		$	—		$	—
	Charges		671			497			—
	Write-offs		(605	)		(38	)		—
	Balance at end of year	$	525		$	459		$	—
Company's Operations in Different Geographic Regions	Information about the Company’s operations in different geographic regions is presented in the tables below (in thousands):
		Year Ended December 31,
		2014			2013			2012
					(As revised)			(As revised)
	Revenue:
	United States	$	99,085		$	63,155		$	47,147
	Germany		22,218			16,521			20,578
	United Kingdom		18,328			13,130			9,100
	All other international		20,922			13,808			6,452
	Total revenue	$	160,553		$	106,614		$	83,277
	Long-lived assets (at year end):
	United States		23,214			8,814			7,976
	Germany		455			362			303
	United Kingdom		429			554			15
	All other international		196			60			83
	Total long-lived assets	$	24,294		$	9,790		$	8,377

Net_Loss_Per_Share_Attributabl1

Net Loss Per Share Attributable to Common Shareholders (Tables)	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Shares Excluded from Computation of Diluted Net Loss Per Share Attributable to Common Stockholders	The following common stock equivalents were excluded from the computation of diluted net loss per share attributable to common stockholders because they had an antidilutive impact (in thousands):
		Year Ended December 31,
		2014		2013		2012
	Options to purchase common stock		2,586		3,652		4,421
	Nonvested restricted stock		1,194		880		341

Business_Combination_Tables

Business Combination (Tables)	12 Months Ended
	Dec. 31, 2014
Mainstreet Commerce LC Acquisition [Member]
Schedule of Assets Acquired and Obligations Assumed	The allocation of the Mainstreet purchase consideration to the assets acquired and liabilities assumed was as follows (in thousands):
	Cash	$	261
	Accounts receivable		511
	Developed technology		2,500
	Customer relationships		300
	Trademarks		10
	Goodwill		8,966
	Other assets / liabilities, net		(151	)
	Total purchase consideration	$	12,397
CQuotient Acquisition [Member]
Schedule of Assets Acquired and Obligations Assumed	The allocation of the CQuotient purchase consideration to the assets acquired and liabilities assumed was as follows (in thousands):
	Cash	$	353
	Accounts receivable		343
	Developed technology		8,500
	Customer relationships		300
	Deferred revenue		(366	)
	Deferred tax liabilities		(3,020	)
	Goodwill		15,413
	Other assets / liabilities, net		(42	)
	Total purchase consideration	$	21,481

Cash_Equivalents_and_ShortTerm1

Cash Equivalents and Short-Term Investments (Tables)	12 Months Ended
	Dec. 31, 2014
Cash and Cash Equivalents [Abstract]
Cash Equivalents and Available-for-Sale Investments	A summary of the Company’s cash equivalents and short-term investments at December 31, 2014 is as follows (in thousands):
		Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
	Cash Equivalents:
	Money market funds	$	140,107	$	—	$	—		$	140,107
	Certificates of deposit		498		—		—			498
	Municipal securities		2,015		—		—			2,015
		$	142,620	$	—	$	—		$	142,620
	Short-Term Investments:
	U.S. government agency bonds	$	21,304	$	1	$	(2	)	$	21,303
	Corporate bonds		6,895		—		(3	)		6,892
	Municipal securities		29,383		2		(7	)		29,378
	Certificates of deposit		27,307		—		—			27,307
		$	84,889	$	3	$	(12	)	$	84,880
	A summary of the Company’s cash equivalents and short-term investments at December 31, 2013 is as follows (in thousands):
		Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
	Cash Equivalents:
	Money market funds	$	226,130	$	—	$	—		$	226,130
	Certificates of deposit		998		—		—			998
	Municipal securities		2,000		—		—			2,000
		$	229,128	$	—	$	—		$	229,128
	Short-Term Investments:
	U.S. government agency bonds	$	4,500	$	1	$	—		$	4,501
	Corporate bonds and commercial paper		3,318		—		(1	)		3,317
	Municipal securities		19,701		4		(2	)		19,703
	Certificates of deposit		9,612		1		(1	)		9,612
		$	37,131	$	6	$	(4	)	$	37,133

Derivative_Instruments_Tables

Derivative Instruments (Tables)	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summary of Outstanding Foreign Currency Forward Contracts	The Company had the following outstanding foreign currency forward contracts as of December 31, 2014 and 2013 (in thousands):
		December 31, 2014				December 31, 2013
	Currency	Notional		USD		Notional		USD
		Value		Equivalent		Value		Equivalent
	Euro		6,500	$	7,901		—	$	—
	British Pounds Sterling		3,000	$	4,660		—	$	—

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis	The following table details the fair value measurements within the fair value hierarchy of the Company’s financial assets and liabilities at December 31, 2014 and 2013 (in thousands):
				Fair Value Measurements Using
		Amounts		Quoted Prices		Significant Other		Significant
		at Fair Value		in Active		Observable Inputs		Unobservable
				Markets for		(Level 2)		Inputs (Level 3)
				Identical Assets
				(Level 1)
	At December 31, 2014
	Assets—Cash Equivalents:
	Money market funds	$	140,107	$	140,107	$	—	$	—
	Certificates of deposit		498		—		498		—
	Municipal securities		2,015		—		2,015		—
	Assets—Short-Term Investments:
	U.S. government agency bonds	$	21,303	$	—	$	21,303	$	—
	Corporate bonds		6,892		—		6,892		—
	Municipal securities		29,378		—		29,378		—
	Certificates of deposit		27,307		—		27,307		—
	Assets—Derivative Instruments:
	Foreign currency forward contracts	$	69	$	—	$	69	$	—
	At December 31, 2013
	Assets—Cash Equivalents:
	Money market funds	$	226,130	$	226,130	$	—	$	—
	Certificates of deposit		998		—		998		—
	Municipal securities		2,000		—		2,000		—
	Assets—Short-Term Investments:
	U.S. government agency bonds	$	4,501	$	—	$	4,501	$	—
	Corporate bonds and commercial paper		3,317		—		3,317		—
	Municipal securities		19,703		—		19,703		—
	Certificates of deposit		9,612		—		9,612		—

Property_and_Equipment_Tables

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Components of Property and Equipment	Property and equipment as of December 31, 2014 and 2013 consist of the following (in thousands):
		December 31,
		2014			2013
	Computer equipment	$	24,700		$	18,976
	Purchased software, including internal use software		6,742			4,134
	Leasehold improvements		1,078			893
	Office furniture		1,352			1,177
	Property and equipment—at cost		33,872			25,180
	Less: accumulated depreciation and amortization		(19,844	)		(15,390	)
	Property and equipment—net	$	14,028		$	9,790

Goodwill_and_Purchased_Intangi1

Goodwill and Purchased Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of Changes in Carrying Amount of Goodwill	Goodwill—Changes in the carrying amount of goodwill in the year ended December 31, 2014 are as follows (in thousands):
	Balance, December 31, 2013	$	—
	Additions		24,379
	Balance, December 31, 2014	$	24,379
Schedule of Intangible Assets Acquired	Purchased Intangible Assets—Intangible assets acquired as of December 31, 2014 are as follows (in thousands):
				As of December 31, 2014
		Weighted Average		Gross Carrying		Accumulated		Net Book Value
		Life (Years)		Amount		Amortization
	Developed technology		5	$	11,000	$	1,242	$	9,758
	Customer relationships		4		600		92		508
	Trademarks		1		10		10		—
	Total		4.9	$	11,610	$	1,344	$	10,266
Schedule of Future Estimated Amortization Expense for Acquired Intangible Assets	Future estimated amortization expense for acquired intangible assets as of December 31, 2014 is as follows (in thousands):
	2015	$	2,474
	2016		2,277
	2017		2,179
	2018		2,002
	2019		1,334
	Total	$	10,266

Noncontrolling_Interest_Tables

Noncontrolling Interest (Tables)	12 Months Ended
	Dec. 31, 2014
Noncontrolling Interest [Abstract]
Summary of Changes in Redeemable Noncontrolling Interests Classified as Temporary Equity in Balance Sheet	The changes in the redeemable noncontrolling interests classified as temporary equity in the balance sheet for the year ended December 31, 2014 are as follows (in thousands):
	Balance, December 31, 2013	$	—
	Contribution from noncontrolling interests		830
	Net loss attributable to noncontrolling interests		(7	)
	Balance, December 31, 2014	$	823

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Company's Obligation for Lease Payments	The Company’s obligation for lease payments is as follows at December 31, 2014 (in thousands):
	Years Ending December 31
	2015	$	4,169
	2016		4,195
	2017		3,742
	2018		3,085
	2019		2,509
	Thereafter		1,241
	Total minimum lease payments	$	18,941

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation Expense	The following table presents stock-based compensation expense included in the Company’s consolidated statements of operations and comprehensive loss (in thousands):
		Year Ended December 31,
		2014			2013			2012
	Cost of subscription revenue	$	701		$	391		$	175
	Cost of service revenue		1,967			1,179			722
	Sales and marketing		7,474			4,296			1,842
	Research and development		7,513			3,574			1,509
	General and administrative		8,975			5,248			2,795
		$	26,630		$	14,688		$	7,043
Assumptions Used to Compute Fair value of Stock Options Granted	The fair value of the stock options granted was calculated using the following key assumptions:
		Year Ended December 31,
		2014			2013			2012
	Risk-free interest rate		1.8	%		2.1	%		1.3	%
	Expected dividend yield		—			—			—
	Expected term (in years)		6			6			6
	Weighted average expected volatility		49.2	%		50.4	%		57	%
Summary of Stock Options Activity	The summary of stock option activity for the year ended December 31, 2014 is as follows (in thousands, except per share and term information):
		Shares			Weighted-			Weighted-			Aggregate
					Average			Average			Intrinsic
					Exercise			Remaining			Value
					Price			Contractual
								Life (in
								Years)
	Outstanding—January 1, 2014		2,994		$	12.39
	Granted		194			64.31
	Forfeited		(28	)		30.34
	Expired or cancelled		(2	)		12.49
	Exercised		(572	)		11.97
	Outstanding—December 31, 2014		2,586		$	16.18			6.25		$	108,329
	Exercisable—December 31, 2014		1,928		$	7.91			5.63		$	95,709
	Options vested and expected to vest—December 31, 2014		2,553		$	15.8			6.22		$	107,849
Summary of Stock-Based Awards Granted and Exercised	The following table summarizes information relating to stock options granted and exercised (in thousands, except per share data):
		Year Ended December 31,
		2014			2013			2012
	Weighted average grant date fair value per share	$	31.79		$	16.87		$	16.49
	Aggregate intrinsic value of options exercised		29,363			42,099			21,402
	Cash proceeds received upon exercise of options		6,848			7,948			1,282
Summary of Restricted Stock Activity	The summary of restricted stock awards activity is as follows (in thousands, except per share data):
		Number of			Weighted-
		Shares			Average
					Grant Date
					Fair Value
	Nonvested at December 31, 2013		961		$	32.51
	Granted		686			66.18
	Vested		(414	)		32.42
	Forfeited		(39	)		46.98
	Nonvested at December 31, 2014		1,194		$	51.4
Summary of Restricted Stock Granted and Exercised	The following table summarizes information relating to restricted stock granted and vested (in thousands, except per share data):
		Year Ended December 31,
		2014			2013			2012
	Weighted average grant date fair value per share	$	66.18		$	33.13		$	30.92
	Total fair value of restricted stock vested		25,801			6,418			2,350

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Provision for Income Taxes	The provision for income taxes for the years ended December 31, 2014, 2013 and 2012 consists of the following (in thousands):
		December 31,
		2014			2013			2012
	Loss before income taxes:
	Domestic	$	(31,431	)	$	(19,062	)	$	(5,050	)
	International		2,321			1,634			1,129
		$	(29,110	)	$	(17,428	)	$	(3,901	)
		December 31,
		2014			2013			2012
	Current income tax provision:
	Federal	$	—		$	—		$	—
	State		72			52			56
	Foreign		776			457			368
	Total current income tax provision		848			509			424
	Deferred income tax (benefit) provision:
	Federal		(2,795	)		—			—
	State		(3	)		—			—
	Foreign		(100	)		65			(3	)
	Total deferred income tax (benefit) provision		(2,898	)		65			(3	)
	Total income tax (benefit) provision	$	(2,050	)	$	574		$	421
Effective Income Tax Rate Reconciliation	The differences in total provision for income taxes that would result from applying the 34% federal statutory rate to (loss) income before provision for income taxes and the reported provision for income taxes are as follows:
		Years Ended December 31,
		2014			2013			2012
					(As revised)			(As revised)
	U.S. Federal tax expense at statutory rates		34	%		34	%		34	%
	State income taxes, net of federal tax benefit		2	%		0.5	%		(1	)%
	Foreign rate differential		1	%		0.5	%		1	%
	Permanent differences		6	%		(4	)%		(5	)%
	Stock-based compensation		(6	)%		(3	)%		(6	)%
	Uncertain tax provisions		(1	)%		(1	)%		(2	)%
	Valuation allowance		(29	)%		(30	)%		(32	)%
			7	%		(3	)%		(11	)%
Components of Net Deferred Tax Assets	Components of the net deferred tax assets as of December 31, 2014 and 2013 are as follows (in thousands):
		December 31,
		2014			2013
					(As revised)
	Operating loss carryforwards	$	17,804		$	12,948
	Capitalized research and development costs		4,226			8,433
	Accrued expenses		7,411			5,630
	Research and development credits		3,738			1,160
	Deferred revenue		1,578			(311	)
	Stock compensation		5,367			2,850
	Depreciation		167			296
	Other		24			3
	Total deferred tax assets		40,315			31,009
	Valuation allowance for deferred tax assets		(40,493	)		(31,074	)
	Net deferred tax liability	$	(178	)	$	(65	)
Changes to Company's Uncertain Tax Positions	The following table indicates the changes to the Company’s unrecognized tax benefits for the years ended December 31 (in thousands):
		2014			2013			2012
	Beginning balance	$	1,418		$	1,061		$	805
	Decrease related to current tax year		(409	)		—			—
	Increase related to current tax year		497			357			256
	Ending balance	$	1,506		$	1,418		$	1,061

Selected_Quarterly_Information1

Selected Quarterly Information (Tables)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Summary of Selected Quarterly Information	The following tables summarize the effects of the revisions on our previously issued unaudited condensed consolidated financial statements:
		2014
		1st Quarter								2nd Quarter								3rd Quarter								4th
																										Quarter
		As Previously			Adjustment		As Revised			As Previously			Adjustment		As Revised			As Previously			Adjustment		As Revised
		Reported								Reported								Reported
		(in thousands, except per share amounts)
	Revenue	$	32,178		$	396	$	32,574		$	36,085		$	661	$	36,746		$	38,227		$	504	$	38,731		$	52,502
	Gross profit		23,270			396		23,666			26,080			661		26,741			27,442			504		27,946			40,152
	Loss from operations		(8,496	)		396		(8,100	)		(9,025	)		661		(8,364	)		(5,651	)		504		(5,147	)		(6,181	)
	Loss before provision for income taxes		(8,494	)		396		(8,098	)		(8,958	)		661		(8,297	)		(6,654	)		504		(6,150	)		(6,565	)
	Net loss		(8,759	)		396		(8,363	)		(9,185	)		661		(8,524	)		(6,853	)		504		(6,349	)		(3,824	)
	Net loss attributable to noncontrolling interest		—			—		—			—			—		—			—			—		—			7
	Net loss attributable to Demandware		(8,759	)		396		(8,363	)		(9,185	)		661		(8,524	)		(6,853	)		504		(6,349	)		(3,817	)
	Basic net loss per share attributable to Demandware	$	(0.25	)	$	0.01	$	(0.24	)	$	(0.27	)	$	0.02	$	(0.25	)	$	(0.20	)	$	0.02	$	(0.18	)	$	(0.11	)
	Diluted net loss per share attributable to Demandware	$	(0.25	)	$	0.01	$	(0.24	)	$	(0.27	)	$	0.02	$	(0.25	)	$	(0.20	)	$	0.02	$	(0.18	)	$	(0.11	)
		2013
		1st Quarter								2nd Quarter								3rd Quarter								4th Quarter
		As			Adjustment		As			As			Adjustment		As			As			Adjustment		As			As			Adjustment		As
		Previously					Revised			Previously					Revised			Previously					Revised			Previously					Revised
		Reported								Reported								Reported								Reported
		(in thousands, except per share amounts)
	Revenue	$	20,514		$	290	$	20,804		$	23,207		$	342	$	23,549		$	24,479		$	1,162	$	25,641		$	35,536		$	1,084	$	36,620
	Gross profit		14,032			290		14,322			16,665			342		17,007			17,428			1,162		18,590			27,594			1,084		28,678
	(Loss) income from operations		(7,317	)		290		(7,027	)		(8,413	)		342		(8,071	)		(6,769	)		1,162		(5,607	)		1,710			1,084		2,794
	(Loss) income before provision for income taxes		(7,753	)		290		(7,463	)		(8,310	)		342		(7,968	)		(6,147	)		1,162		(4,985	)		1,904			1,084		2,988
	Net (loss) income		(7,972	)		290		(7,682	)		(8,455	)		342		(8,113	)		(6,257	)		1,162		(5,095	)		1,804			1,084		2,888
	Basic net (loss) income per share attributable to Demandware	$	(0.27	)	$	0.01	$	(0.26	)	$	(0.28	)	$	0.01	$	(0.27	)	$	(0.20	)	$	0.03	$	(0.17	)	$	0.06		$	0.03	$	0.09
	Diluted net (loss) income per share attributable to Demandware	$	(0.27	)	$	0.01	$	(0.26	)	$	(0.28	)	$	0.01	$	(0.27	)	$	(0.20	)	$	0.03	$	(0.17	)	$	0.05		$	0.03	$	0.08

Organization_and_Basis_of_Pres2

Organization and Basis of Presentation - Previously Reported and Adjusted Consolidated Statements of Operations and Comprehensive Loss (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenue:
Services									$14,674	$10,881	$15,347
Total revenue	52,502	38,731	36,746	32,574	36,620	25,641	23,549	20,804	160,553	106,614	83,277
Gross profit	40,152	27,946	26,741	23,666	28,678	18,590	17,007	14,322	118,505	78,597	58,936
Net loss									-27,060	-18,002	-4,322
Net loss attributable to common stockholders									-27,053	-18,002	-5,494
Net loss per share attributable to common stockholders, basic and diluted									($0.78)	($0.58)	($0.23)
Comprehensive loss									-27,476	-17,921	-4,286
As Previously Reported [Member]
Revenue:
Services										8,003	11,545
Total revenue		38,227	36,085	32,178	35,536	24,479	23,207	20,514		103,736	79,475
Gross profit		27,442	26,080	23,270	27,594	17,428	16,665	14,032		75,719	55,134
Net loss										-20,880	-8,124
Net loss attributable to common stockholders										-20,880	-9,296
Net loss per share attributable to common stockholders, basic and diluted										($0.68)	($0.39)
Comprehensive loss										-20,799	-8,088
Adjustment [Member]
Revenue:
Services										2,878	3,802
Total revenue		504	661	396	1,084	1,162	342	290		2,878	3,802
Gross profit		504	661	396	1,084	1,162	342	290		2,878	3,802
Net loss										2,878	3,802
Net loss attributable to common stockholders										2,878	3,802
Net loss per share attributable to common stockholders, basic and diluted										$0.10	$0.16
Comprehensive loss										$2,878	$3,802

Organization_and_Basis_of_Pres3

Organization and Basis of Presentation - Previously Reported and Adjusted Consolidated Balance Sheet (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Current liabilities:
Deferred revenue	$22,799	$18,280
Total current liabilities	51,533	41,727
Long-term liabilities:
Deferred revenue	12,168	8,108
Total liabilities:	65,125	52,243
Stockholders' equity:
Accumulated deficit	-112,538	-85,485
Total stockholders' equity:	279,222	271,688	103,795	-79,217
Total liabilities and stockholders' equity:	345,170	323,931
As Previously Reported [Member]
Current liabilities:
Deferred revenue		19,609
Total current liabilities		43,056
Long-term liabilities:
Deferred revenue		18,862
Total liabilities:		64,326
Stockholders' equity:
Accumulated deficit		-97,568
Total stockholders' equity:		259,605		-84,620
Total liabilities and stockholders' equity:		323,931
Adjustment [Member]
Current liabilities:
Deferred revenue		-1,329
Total current liabilities		-1,329
Long-term liabilities:
Deferred revenue		-10,754
Total liabilities:		-12,083
Stockholders' equity:
Accumulated deficit		12,083
Total stockholders' equity:		$12,083

Organization_and_Basis_of_Pres4

Organization and Basis of Presentation - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Organization [Line Items]
Deferred revenue	$8,045	$8,841	($3,219)
Prior period adjustment			5,403
Net loss per share attributable to common stockholders, basic and diluted				$0.34
Adjustments to Service Revenue and Total Revenue [Member]
Organization [Line Items]
Prior period adjustment				5,400
Adjustment to Net Income Loss [Member]
Organization [Line Items]
Prior period adjustment				1,300
Adjustment to Deferred Revenue and Accumulated Deficit [Member]
Organization [Line Items]
Prior period adjustment			9,200	5,400
Adjustment to Working Capital [Member]
Organization [Line Items]
Prior period adjustment			900	400
As Previously Reported [Member]
Organization [Line Items]
Deferred revenue		2,900	3,800
As Previously Reported [Member] | Adjustment to Net Income Loss [Member]
Organization [Line Items]
Prior period adjustment				$6,700
Restatement Adjustment [Member]
Organization [Line Items]
Net loss per share attributable to common stockholders, basic and diluted				$1.75

Summary_of_Significant_Account3

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	Customer	Customer	Customer
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Foreign currency transaction (losses) gains	($1,700,000)	$600,000	$100,000
Liquid investments maturity	90 days
Cash and cash equivalents	158,827,000	242,425,000	58,877,000	14,939,000
Number of reseller		1
Number of customer comprised more than 10% of revenue	0	0	0
Estimated useful life of capitalized internal use software costs	4 years
Internal use software development costs	0	0	200,000
Amortization expense related to internal use software	200,000	200,000	100,000
Net book value of capitalized internal use software	400,000	600,000
Goodwill	24,379,000	0
Impairment of intangible Assets	0
Purchased intangible assets		0
Advertising expense	8,400,000	6,200,000	4,000,000
Tax benefit realized	50.00%
Minimum [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life of property and equipment	3 years
Maximum [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life of property and equipment	5 years
Customer Relationships [Member] | Minimum [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Estimated useful life of customers	6 years
Sales Revenue, Net [Member] | Customer Concentration Risk [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Major customer percentage	10.00%	10.00%	10.00%
Accounts Receivable [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Number of customer comprised more than 10% of revenue	0
Accounts Receivable [Member] | Credit Concentration Risk [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Major customer percentage		12.00%
Money Market Funds [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Cash and cash equivalents	140,100,000	226,100,000
Marketable Debt Securities [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Cash and cash equivalents	$2,500,000	$3,000,000

Summary_of_Significant_Account4

Summary of Significant Accounting Policies - Allowance for Doubtful Accounts Receivable (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Accounting Policies [Abstract]
Balance at beginning of year	$459
Charges	671	497
Write-offs	-605	-38
Balance at end of year	$525	$459

Summary_of_Significant_Account5

Summary of Significant Accounting Policies - Company's Operations in Different Geographic Regions (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$52,502	$38,731	$36,746	$32,574	$36,620	$25,641	$23,549	$20,804	$160,553	$106,614	$83,277
Total long-lived assets	24,294				9,790				24,294	9,790	8,377
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue									99,085	63,155	47,147
Total long-lived assets	23,214				8,814				23,214	8,814	7,976
Germany [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue									22,218	16,521	20,578
Total long-lived assets	455				362				455	362	303
United Kingdom [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue									18,328	13,130	9,100
Total long-lived assets	429				554				429	554	15
All Other International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue									20,922	13,808	6,452
Total long-lived assets	$196				$60				$196	$60	$83

Net_Loss_Per_Share_Attributabl2

Net Loss Per Share Attributable to Common Shareholders - Shares Excluded from Computation of Diluted Net Loss Per Share Attributable to Common Stockholders (Detail)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities	2,586	3,652	4,421
Restricted Stock Awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities	1,194	880	341

Business_Combination_Additiona

Business Combination - Additional Information (Detail) (USD $)	0 Months Ended	12 Months Ended	0 Months Ended
	Jan. 22, 2014	Dec. 31, 2014	Oct. 09, 2014
Business Acquisition [Line Items]
Acquisition date		22-Jan-14
Percentage of equity acquired	100.00%
Business acquisition, cash consideration	$19,400,000
Amount held in escrow	10,000,000
Amount in escrow is reserved for payments to employees for post combination employment services	7,000,000
Business acquisition, escrow withheld as protection against certain losses	3,000,000
Purchase price of business acquisition	12,400,000
Transaction costs in connection with acquisition	100,000
CQuotient Acquisition [Member]
Business Acquisition [Line Items]
Acquisition date		9-Oct-14
Business acquisition, cash consideration			21,500,000
Amount held in escrow			3,200,000
Purchase price of business acquisition		21,481,000
Transaction costs in connection with acquisition			400,000
Percentage of interest acquired			100.00%
Additional consideration			$3,400,000

Business_Combination_Schedule_

Business Combination - Schedule of Assets Acquired and Obligations Assumed (Detail) (USD $)	Dec. 31, 2014	Jan. 22, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Business Acquisition [Line Items]
Goodwill	$24,379		$0
Total purchase consideration		12,400
Mainstreet Commerce LC Acquisition [Member]
Business Acquisition [Line Items]
Cash	261
Accounts receivable	511
Goodwill	8,966
Other assets / liabilities, net	-151
Total purchase consideration	12,397
Mainstreet Commerce LC Acquisition [Member] | Developed Technology [Member]
Business Acquisition [Line Items]
Finite lived intangible assets	2,500
Mainstreet Commerce LC Acquisition [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Finite lived intangible assets	300
Mainstreet Commerce LC Acquisition [Member] | Trademarks [Member]
Business Acquisition [Line Items]
Finite lived intangible assets	10
CQuotient Acquisition [Member]
Business Acquisition [Line Items]
Deferred revenue	-366
Cash	353
Deferred tax liabilities	-3,020
Accounts receivable	343
Goodwill	15,413
Other assets / liabilities, net	-42
Total purchase consideration	21,481
CQuotient Acquisition [Member] | Developed Technology [Member]
Business Acquisition [Line Items]
Finite lived intangible assets	8,500
CQuotient Acquisition [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Finite lived intangible assets	$300

Cash_Equivalents_and_ShortTerm2

Cash Equivalents and Short-Term Investments - Cash Equivalents and Available-for-Sale Investments (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Short-Term Investments [Member]
Cash and Cash Equivalents [Line Items]
Cash Equivalents - Amortized Cost		$229,128
Unrealized Gains		0
Unrealized Losses		0
Cash Equivalents - Fair Value		229,128
Short-Term Investments - Amortized Cost	84,889	37,131
Unrealized Gains	3	6
Unrealized Losses	-12	-4
Short-Term Investments - Fair Value	84,880	37,133
Short-Term Investments [Member] | U.S. Government Agency Bonds [Member]
Cash and Cash Equivalents [Line Items]
Short-Term Investments - Amortized Cost	21,304	4,500
Unrealized Gains	1	1
Unrealized Losses	-2
Short-Term Investments - Fair Value	21,303	4,501
Short-Term Investments [Member] | Corporate Bonds and Commercial Paper [Member]
Cash and Cash Equivalents [Line Items]
Short-Term Investments - Amortized Cost		3,318
Unrealized Losses		-1
Short-Term Investments - Fair Value		3,317
Short-Term Investments [Member] | Municipal Securities [Member]
Cash and Cash Equivalents [Line Items]
Cash Equivalents - Amortized Cost		2,000
Unrealized Gains		0
Unrealized Losses		0
Cash Equivalents - Fair Value		2,000
Short-Term Investments - Amortized Cost	29,383	19,701
Unrealized Gains	2	4
Unrealized Losses	-7	-2
Short-Term Investments - Fair Value	29,378	19,703
Short-Term Investments [Member] | Certificates of Deposit [Member]
Cash and Cash Equivalents [Line Items]
Cash Equivalents - Amortized Cost		998
Unrealized Gains		0
Unrealized Losses		0
Cash Equivalents - Fair Value		998
Short-Term Investments - Amortized Cost	27,307	9,612
Unrealized Gains		1
Unrealized Losses		-1
Short-Term Investments - Fair Value	27,307	9,612
Short-Term Investments [Member] | Money Market Funds [Member]
Cash and Cash Equivalents [Line Items]
Cash Equivalents - Amortized Cost		226,130
Unrealized Gains		0
Unrealized Losses		0
Cash Equivalents - Fair Value		226,130
Short-Term Investments [Member] | Corporate Bonds [Member]
Cash and Cash Equivalents [Line Items]
Short-Term Investments - Amortized Cost	6,895
Unrealized Losses	-3
Short-Term Investments - Fair Value	6,892
Cash Equivalents [Member]
Cash and Cash Equivalents [Line Items]
Cash Equivalents - Amortized Cost	142,620
Unrealized Gains	0
Unrealized Losses	0
Cash Equivalents - Fair Value	142,620
Cash Equivalents [Member] | Municipal Securities [Member]
Cash and Cash Equivalents [Line Items]
Cash Equivalents - Amortized Cost	2,015
Unrealized Gains	0
Unrealized Losses	0
Cash Equivalents - Fair Value	2,015	2,000
Cash Equivalents [Member] | Certificates of Deposit [Member]
Cash and Cash Equivalents [Line Items]
Cash Equivalents - Amortized Cost	498
Unrealized Gains	0
Unrealized Losses	0
Cash Equivalents - Fair Value	498	998
Cash Equivalents [Member] | Money Market Funds [Member]
Cash and Cash Equivalents [Line Items]
Cash Equivalents - Amortized Cost	140,107
Unrealized Gains	0
Unrealized Losses	0
Cash Equivalents - Fair Value	$140,107	$226,130

Cash_Equivalents_and_ShortTerm3

Cash Equivalents and Short-Term Investments - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2014
Cash and Cash Equivalents [Abstract]
Contractual maturity expiration dates	1 year

Derivative_Instruments_Summary

Derivative Instruments - Summary of Outstanding Foreign Currency Forward Contracts (Detail) (Foreign Currency Forward Contracts [Member], USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Euro [Member]
Derivative [Line Items]
Foreign currency forward contracts notional value	$6,500
British Pounds Sterling [Member]
Derivative [Line Items]
Foreign currency forward contracts notional value	3,000
USD Equivalent [Member] | Euro [Member]
Derivative [Line Items]
Foreign currency forward contracts notional value	7,901
USD Equivalent [Member] | British Pounds Sterling [Member]
Derivative [Line Items]
Foreign currency forward contracts notional value	$4,660

Derivative_Instruments_Additio

Derivative Instruments - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Income (Expense) [Member]
Summary Of Derivative Instruments [Line Items]
Unrealized gain or loss recognized from forward contracts	$69,000	$0	$0
Prepaid Expenses and Other Current Assets [Member]
Summary Of Derivative Instruments [Line Items]
Fair value of forward contracts	69,000	0
Fair Value Measurements Using Significant Unobservable Inputs (Level 3) [Member]
Summary Of Derivative Instruments [Line Items]
Financial asset and liabilities net	$0	$0

Fair_Value_Measurements_Schedu

Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Short-Term Investments	$84,880,000	$37,133,000
Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Short-Term Investments	6,892,000
Cash Equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Cash Equivalents	142,620,000
Cash Equivalents [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Cash Equivalents	140,107,000	226,130,000
Cash Equivalents [Member] | Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Cash Equivalents	498,000	998,000
Cash Equivalents [Member] | Municipal Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Cash Equivalents	2,015,000	2,000,000
Short-Term Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Cash Equivalents		229,128,000
Short-Term Investments [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Cash Equivalents		226,130,000
Short-Term Investments [Member] | Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Cash Equivalents		998,000
Assets-Short-Term Investments	27,307,000	9,612,000
Short-Term Investments [Member] | Municipal Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Cash Equivalents		2,000,000
Assets-Short-Term Investments	29,378,000	19,703,000
Short-Term Investments [Member] | U.S. Government Agency Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Short-Term Investments	21,303,000	4,501,000
Short-Term Investments [Member] | Corporate Bonds and Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Short-Term Investments		3,317,000
Derivative Instruments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Foreign currency forward contracts	69,000
Fair Value Measurements Using Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Cash Equivalents [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Cash Equivalents	140,107,000	226,130,000
Fair Value Measurements Using Significant Other Observable Inputs (Level 2) [Member] | Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Short-Term Investments	6,892,000
Fair Value Measurements Using Significant Other Observable Inputs (Level 2) [Member] | Cash Equivalents [Member] | Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Cash Equivalents	498,000	998,000
Fair Value Measurements Using Significant Other Observable Inputs (Level 2) [Member] | Cash Equivalents [Member] | Municipal Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Cash Equivalents	2,015,000	2,000,000
Fair Value Measurements Using Significant Other Observable Inputs (Level 2) [Member] | Short-Term Investments [Member] | Certificates of Deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Short-Term Investments	27,307,000	9,612,000
Fair Value Measurements Using Significant Other Observable Inputs (Level 2) [Member] | Short-Term Investments [Member] | Municipal Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Short-Term Investments	29,378,000	19,703,000
Fair Value Measurements Using Significant Other Observable Inputs (Level 2) [Member] | Short-Term Investments [Member] | U.S. Government Agency Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Short-Term Investments	21,303,000	4,501,000
Fair Value Measurements Using Significant Other Observable Inputs (Level 2) [Member] | Short-Term Investments [Member] | Corporate Bonds and Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Short-Term Investments		3,317,000
Fair Value Measurements Using Significant Other Observable Inputs (Level 2) [Member] | Derivative Instruments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets-Foreign currency forward contracts	$69,000

Property_and_Equipment_Compone

Property and Equipment - Components of Property and Equipment (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]
Property and equipment at cost	$33,872	$25,180
Less: accumulated depreciation and amortization	-19,844	-15,390
Property and equipment net	14,028	9,790
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	24,700	18,976
Purchased Software, Including Internal Use Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	6,742	4,134
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	1,078	893
Office Furniture [Member]
Property, Plant and Equipment [Line Items]
Property and equipment at cost	$1,352	$1,177

Property_and_Equipment_Additio

Property and Equipment - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property Plant and Equipment Useful Life and Values [Abstract]
Depreciation and amortization expense	$6,601	$4,385	$3,439

Recovered_Sheet1

Goodwill And Purchased Intangible Assets - Summary of Changes In Carrying Amount Of Goodwill (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Balance, December 31, 2013	$0
Additions	24,379
Balance, December 31, 2014	$24,379

Goodwill_and_Purchased_Intangi2

Goodwill and Purchased Intangible Assets - Schedule of Intangible Assets Acquired (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$11,610,000
Accumulated Amortization	1,344,000
Net Book Value	10,266,000	0
Weighted average life (years)	4 years 10 months 24 days
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	11,000,000
Accumulated Amortization	1,242,000
Net Book Value	9,758,000
Weighted average life (years)	5 years
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	600,000
Accumulated Amortization	92,000
Net Book Value	508,000
Weighted average life (years)	4 years
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	10,000
Accumulated Amortization	$10,000
Weighted average life (years)	1 year

Goodwill_and_Purchased_Intangi3

Goodwill and Purchased Intangible Assets - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]
Acquired intangible assets	$10,266,000	$0
Intangible assets, amortization expense	$1,300,000	$0

Goodwill_and_Purchased_Intangi4

Goodwill and Purchased Intangible Assets - Schedule of Future Estimated Amortization Expense for Acquired Intangible Assets (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]
2015	$2,474,000
2016	2,277,000
2017	2,179,000
2018	2,002,000
2019	1,334,000
Net Book Value	$10,266,000	$0

Debt_Additional_Information_De

Debt - Additional Information (Detail) (USD $)	12 Months Ended	1 Months Ended
	Dec. 31, 2014	31-May-13	31-May-12	Dec. 31, 2013
Debt Instrument [Line Items]
Secured revolving credit facility maximum	$5,000,000
Interest at a variable rate above prime rate	0.75%
Shares of common stock purchased on conversion of preferred stock into warrant	23,092
Shares of common stock exercise price	$3.90
Issuance of shares of common stock	20,186
Outstanding borrowings under the Loan	0			3,300,000
Equipment Line of Credit [Member]
Debt Instrument [Line Items]
Available borrowings	0
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Available borrowings	0
Equipment Line of Credit [Member]
Debt Instrument [Line Items]
Initial drawdown of loan due in equal monthly payments	36 equal months
Annual interest rate	3.75%
Software Finance Agreement [Member]
Debt Instrument [Line Items]
Outstanding borrowings under the Loan	0			900,000
Purchase of software license			1,800,000
Increased financed amount		$600,000

Noncontrolling_Interest_Additi

Noncontrolling Interest - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014
Noncontrolling Interest [Line Items]
Estimated redemption value of the redeemable noncontrolling interest	$0
Demandware K.K Joint Venture [Member]
Noncontrolling Interest [Line Items]
Contribution to joint venture	2,500,000
Percentage of contribution to joint venture	75.00%
Related Party [Member] | Demandware K.K Joint Venture [Member]
Noncontrolling Interest [Line Items]
Contribution to joint venture	$800,000
Percentage of contribution to joint venture	25.00%

Noncontrolling_Interest_Summar

Noncontrolling Interest - Summary of Changes in Redeemable Noncontrolling Interests Classified as Temporary Equity in Balance Sheet (Detail) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2014
Noncontrolling Interest [Abstract]
Balance, December 31, 2013
Contribution from noncontrolling interests		830
Net loss attributable to noncontrolling interests	7	-7
Balance, December 31, 2014	$823	$823

Commitments_and_Contingencies_1

Commitments and Contingencies - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Long-term Purchase Commitment [Line Items]
Rent expense	$3.40	$2.60	$2.10
Operating lease expiration year	2023
Operating lease period	24 months
Agreement expire date	2016-01
Co-location Services [Member]
Long-term Purchase Commitment [Line Items]
Rent expense	5.3	3.2	2.5
Future minimum payments in 2015	4.4
Future minimum payments in 2016	$1.70

Commitments_and_Contingencies_2

Commitments and Contingencies - Company's Obligation for Lease Payments (Detail) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
2015	$4,169
2016	4,195
2017	3,742
2018	3,085
2019	2,509
Thereafter	1,241
Total minimum lease payments	$18,941

Capitalization_Additional_Info

Capitalization - Additional Information (Detail) (USD $)	0 Months Ended
	Mar. 20, 2012	Dec. 31, 2014	Dec. 31, 2013
Equity [Abstract]
Common stock, shares authorized		240,000,000	240,000,000
Common stock, par value		$0.01	$0.01
Preferred stock, shares authorized		10,000,000	10,000,000
Preferred stock, par value		$0.01	$0.01
Preferred stock, shares issued		0
Preferred stock, shares outstanding		0
Redeemable convertible preferred stock converted into share of common stock upon closing of IPO	18,028,763

Warrants_Additional_Informatio

Warrants - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2012
Class of Warrant or Right [Line Items]
Shares of common stock purchased on conversion of preferred stock into warrant	23,092
Shares of common stock purchased on conversion of preferred stock into warrant, price per share	$3.90
Exercisable warrant, expiration date	Jul-18
Fair value of warrant at the time of conversion of warrant upon closing of IPO	$0.50
Issuance of common stock	20,186
Other Income Expense [Member]
Class of Warrant or Right [Line Items]
Income (loss) from change in fair value of warrant		($0.40)

StockBased_Compensation_StockB

Stock-Based Compensation - Stock-Based Compensation Expense (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation cost	$26,630,000	$14,688,000	$7,043,000
Cost of Subscription Revenue [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation cost	701,000	391,000	175,000
Cost of Services Revenue [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation cost	1,967,000	1,179,000	722,000
Sales and Marketing [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation cost	7,474,000	4,296,000	1,842,000
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation cost	7,513,000	3,574,000	1,509,000
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation cost	$8,975,000	$5,248,000	$2,795,000

StockBased_Compensation_Additi

Stock-Based Compensation - Additional Information (Detail) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 06, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$26,630,000	$14,688,000	$7,043,000
Common stock, shares authorized	240,000,000	240,000,000
Restricted stock unit,Granted	686,000
Performance-based restricted stock vested	414,000
Contingent consideration payable	3,400,000
2012 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining common stock available under plan	4,846,670
Contingent Payment in Cash or Shares [Member] | CQuotient Acquisition [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	300,000	0	0
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	6,400,000	6,100,000	4,200,000
Share-based compensation vesting period	4 years
Unrecognized compensation expense	11,700,000
Weighted average period	2 years 3 months 18 days
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	19,500,000	8,400,000	2,800,000
Weighted average period	2 years 10 months 24 days
Restricted stock unit,Granted	25,000	25,000
Performance-based restricted stock vested	25,801,000	6,418,000	2,350,000
Unrecognized compensation expense	50,400,000
Common stock , Fair value	$66.18	$33.13	$30.92
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance-based restricted stock vested	25,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock unit,Granted				16,875
Common stock , Fair value				$60.08
Restricted stock units granted expense	600,000	0
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	400,000	200,000
Stock Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$300,000
Maximum [Member] | 2012 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock pursuant to stock options and stock awards, shares issued	8,126,768
Maximum [Member] | Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation vesting period	4 years
Minimum [Member] | Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation vesting period	2 years

StockBased_Compensation_Assump

Stock-Based Compensation - Assumptions Used to Compute Fair value of Stock Options Granted (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Risk-free interest rate	1.80%	2.10%	1.30%
Expected dividend yield	0.00%	0.00%	0.00%
Expected term (in years)	6 years	6 years	6 years
Weighted average expected volatility	49.20%	50.40%	57.00%

StockBased_Compensation_Summar

Stock-Based Compensation - Summary of Stock Option Activity (Detail) (USD $)	12 Months Ended	144 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Outstanding Shares - January 1, 2014	2,994
Granted, Shares	194
Forfeited, Shares	-28
Expired or cancelled, Shares	-2
Exercised, Shares	-572
Outstanding Shares - December 31, 2014	2,586	2,586
Exercisable Shares - December 31, 2014	1,928	1,928
Options vested and expected to vest Shares - December 31, 2014	2,553	2,553
Outstanding Weighted-Average Exercise Price - January 1, 2014	$12.39
Granted, Weighted-Average Exercise Price	$64.31
Forfeited, Weighted-Average Exercise Price	$30.34
Expired or cancelled, Weighted-Average Exercise Price	$12.49
Exercised, Weighted-Average Exercise Price	$11.97
Outstanding Weighted-Average Exercise Price - December 31, 2014	$16.18	$16.18
Exercisable Weighted-Average Exercise Price - December 31, 2014	$7.91	$7.91
Options vested and expected to vest, Weighted-Average Exercise Price - December 31, 2014	$15.80	$15.80
Outstanding, Weighted-Average Remaining Contractual Life (in Years)		6 years 3 months
Exercisable, Weighted-Average Remaining Contractual Life (in Years) - December 31, 2014		5 years 7 months 17 days
Options vested and expected to vest, Weighted-Average Remaining Contractual Life (in Years) - December 31, 2014		6 years 2 months 19 days
Outstanding, Aggregate Intrinsic Value - December 31, 2014	$108,329	$108,329
Exercisable, Aggregate Intrinsic Value - December 31, 2014	95,709	95,709
Options vested and expected to vest, Aggregate Intrinsic Value - December 31, 2014	$107,849	$107,849

StockBased_Compensation_Summar1

Stock-Based Compensation - Summary of Stock-Based Awards Granted and Exercised (Detail) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Weighted average grant date fair value per share	$31.79	$16.87	$16.49
Aggregate intrinsic value of options exercised	$29,363	$42,099	$21,402
Cash proceeds received upon exercise of options	$6,848	$7,948	$1,282

StockBased_Compensation_Summar2

Stock-Based Compensation - Summary of Restricted Stock Activity (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested, Number of Shares, Beginning Balance	961,000
Granted, Number of Shares	686,000
Vested, Number of Shares	-414,000
Forfeited, Number of Shares	-39,000
Nonvested, Number of Shares, Ending Balance	1,194,000
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Number of Shares	25,000	25,000
Vested, Number of Shares	-25,801,000	-6,418,000	-2,350,000
Nonvested, Weighted Average Grant Date Fair Value, Beginning Balance	$32.51
Granted, Weighted Average Grant Date Fair Value	$66.18	$33.13	$30.92
Vested, Weighted Average Grant Date Fair Value	$32.42
Forfeited, Weighted Average Grant Date Fair Value	$46.98
Nonvested, Weighted Average Grant Date Fair Value, Ending Balance	$51.40	$32.51

StockBased_Compensation_Summar3

Stock-Based Compensation - Summary of Restricted Stock Granted and Exercised (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of restricted stock vested	414,000
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value per share	$66.18	$33.13	$30.92
Total fair value of restricted stock vested	25,801,000	6,418,000	2,350,000

StockBased_Compensation_Plans_

Stock-Based Compensation Plans - Additional Information (Detail) (Employee Stock Purchase Plan [Member], USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated shares, employees to purchase	400,000
Percentage of purchase price of stock	85.00%
Exercise price of share	$51.34	$36.47
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum employee contribution to employee stock purchase plan during the period	$12,500
Exercise price of share	$16.43	$9.62
Number of shares purchased during period	27,088	14,934	0
Shares reserved for future issuance	357,978

Income_Taxes_Provision_for_Inc

Income Taxes - Provision for Income Taxes (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Loss before income taxes:
Domestic									($31,431)	($19,062)	($5,050)
International									2,321	1,634	1,129
Loss before income taxes	-6,565	-6,150	-8,297	-8,098	2,988	-4,985	-7,968	-7,463	-29,110	-17,428	-3,901
Current income tax provision:
Federal									0	0	0
State									72	52	56
Foreign									776	457	368
Total current income tax provision									848	509	424
Deferred income tax (benefit) provision:
Federal									-2,795
State									-3
Foreign									-100	65	-3
Total deferred income tax (benefit) provision									-2,798	65	-3
Total income tax (benefit) provision									($2,050)	$574	$421

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax [Line Items]
Federal statutory rate to (loss) income before provision for income taxes	34.00%	34.00%	34.00%
Valuation allowance increase decrease	$9,400,000	$5,200,000
Federal net operating loss carryforwards	138,800,000
State net operating loss carryforwards	69,600,000
Net operating loss carryforwards expire	Through 2034
Equity impact due to realization of deferred tax assets	35,500,000
Unrecognized tax benefits, income tax penalties and interest accrued	0
Research and Development Tax Credit Carryforwards [Member]
Income Tax [Line Items]
Federal and state research and development tax credit carryforwards	5,000,000
CQuotient Acquisition [Member]
Income Tax [Line Items]
Deferred tax liabilities, valuation allowance	3,000,000
Deferred tax assets, total	3,000,000
State [Member] | Research and Development Tax Credit Carryforwards [Member]
Income Tax [Line Items]
Federal and state research and development tax credit carryforwards	$3,300,000

Income_Taxes_Effective_Income_

Income Taxes - Effective Income Tax Rate Reconciliation (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
U.S. Federal tax expense at statutory rates	34.00%	34.00%	34.00%
State income taxes, net of federal tax benefit	2.00%	0.50%	-1.00%
Foreign rate differential	1.00%	0.50%	1.00%
Permanent differences	6.00%	-4.00%	-5.00%
Stock-based compensation	-6.00%	-3.00%	-6.00%
Uncertain tax provisions	-1.00%	-1.00%	-2.00%
Valuation allowance	-29.00%	-30.00%	-32.00%
Effective income tax rate	7.00%	-3.00%	-11.00%

Income_Taxes_Components_of_Net

Income Taxes - Components of Net Deferred Tax Assets (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Income Tax Disclosure [Abstract]
Operating loss carryforwards	$17,804	$12,948
Capitalized research and development costs	4,226	8,433
Accrued expenses	7,411	5,630
Research and development credits	3,738	1,160
Deferred revenue	1,578	-311
Stock compensation	5,367	2,850
Depreciation	167	296
Other	24	3
Total deferred tax assets	40,315	31,009
Valuation allowance for deferred tax assets	-40,493	-31,074
Net deferred tax liability	($178)	($65)

Income_Taxes_Changes_to_Compan

Income Taxes - Changes to Company's Uncertain Tax Positions (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Beginning balance	$1,418	$1,061	$805
Decrease related to current tax year	-409
Increase related to current tax year	497	357	256
Ending balance	$1,506	$1,418	$1,061

Employee_Benefits_Additional_I

Employee Benefits - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2014
Schedule Of Sale Of Subsidiary [Abstract]
Participants contribution percentage	20.00%

Selected_Quarterly_Information2

Selected Quarterly Information - Summary of Selected Quarterly Information (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule Of Quarterly Financial Information [Line Items]
Revenue	$52,502	$38,731	$36,746	$32,574	$36,620	$25,641	$23,549	$20,804	$160,553	$106,614	$83,277
Gross profit	40,152	27,946	26,741	23,666	28,678	18,590	17,007	14,322	118,505	78,597	58,936
(Loss) income from operations	-6,181	-5,147	-8,364	-8,100	2,794	-5,607	-8,071	-7,027	-27,792	-17,911	-3,357
(Loss) income before provision for income taxes	-6,565	-6,150	-8,297	-8,098	2,988	-4,985	-7,968	-7,463	-29,110	-17,428	-3,901
Net (loss) income	-3,824	-6,349	-8,524	-8,363	2,888	-5,095	-8,113	-7,682	-27,053	-18,002	-4,322
Net loss attributable to noncontrolling interest	7								-7
Net loss attributable to Demandware	-3,817	-6,349	-8,524	-8,363
Basic net (loss) income per share attributable to Demandware	($0.11)	($0.18)	($0.25)	($0.24)	$0.09	($0.17)	($0.27)	($0.26)
Diluted net (loss) income per share attributable to Demandware	($0.11)	($0.18)	($0.25)	($0.24)	$0.08	($0.17)	($0.27)	($0.26)
As Previously Reported [Member]
Schedule Of Quarterly Financial Information [Line Items]
Revenue		38,227	36,085	32,178	35,536	24,479	23,207	20,514		103,736	79,475
Gross profit		27,442	26,080	23,270	27,594	17,428	16,665	14,032		75,719	55,134
(Loss) income from operations		-5,651	-9,025	-8,496	1,710	-6,769	-8,413	-7,317
(Loss) income before provision for income taxes		-6,654	-8,958	-8,494	1,904	-6,147	-8,310	-7,753
Net (loss) income		-6,853	-9,185	-8,759	1,804	-6,257	-8,455	-7,972
Net loss attributable to Demandware		-6,853	-9,185	-8,759
Basic net (loss) income per share attributable to Demandware		($0.20)	($0.27)	($0.25)	$0.06	($0.20)	($0.28)	($0.27)
Diluted net (loss) income per share attributable to Demandware		($0.20)	($0.27)	($0.25)	$0.05	($0.20)	($0.28)	($0.27)
Adjustment [Member]
Schedule Of Quarterly Financial Information [Line Items]
Revenue		504	661	396	1,084	1,162	342	290		2,878	3,802
Gross profit		504	661	396	1,084	1,162	342	290		2,878	3,802
(Loss) income from operations		504	661	396	1,084	1,162	342	290
(Loss) income before provision for income taxes		504	661	396	1,084	1,162	342	290
Net (loss) income		504	661	396	1,084	1,162	342	290
Net loss attributable to Demandware		$504	$661	$396
Basic net (loss) income per share attributable to Demandware		$0.02	$0.02	$0.01	$0.03	$0.03	$0.01	$0.01
Diluted net (loss) income per share attributable to Demandware		$0.02	$0.02	$0.01	$0.03	$0.03	$0.01	$0.01

Subsequent_Events_Additional_I

Subsequent Events - Additional Information (Detail) (USD $)	0 Months Ended	12 Months Ended	0 Months Ended
In Millions, unless otherwise specified	Jan. 22, 2014	Dec. 31, 2014	Jan. 12, 2015
Subsequent Event [Line Items]
Acquisition date		22-Jan-14
Business acquisition, cash consideration	$19.40
Transaction costs in connection with acquisition	0.1
Tomax Acquisition [Member]
Subsequent Event [Line Items]
Acquisition date		12-Jan-14
Tomax Acquisition [Member] | Minimum [Member]
Subsequent Event [Line Items]
Cash consideration payment period		1 year 6 months
Tomax Acquisition [Member] | Maximum [Member]
Subsequent Event [Line Items]
Cash consideration payment period		2 years
Subsequent Events [Member] | Tomax Acquisition [Member]
Subsequent Event [Line Items]
Percentage of interest acquired			100.00%
Business acquisition, cash consideration			60
Consideration in escrow account			12
Additional consideration			15
General and Administrative [Member] | Tomax Acquisition [Member]
Subsequent Event [Line Items]
Transaction costs in connection with acquisition		0.9