Opower 10-Q 13 Nov 14 2014 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2014	Nov. 01, 2014
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q3	'
Trading Symbol	'OPWR	'
Entity Registrant Name	'OPOWER, INC.	'
Entity Central Index Key	'0001412043	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Non-accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	49,842,511

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$137,565	$28,819
Accounts receivable, net of allowance for doubtful accounts of $361 and $0 at December 31, 2013 and September 30, 2014, respectively	21,529	20,228
Prepaid expenses and other current assets	3,854	1,988
Total current assets	162,948	51,035
Property and equipment, net	15,017	10,813
Other assets	206	1,287
Total assets	178,171	63,135
Current liabilities:	'	'
Accounts payable	943	1,163
Accrued expenses	5,545	4,452
Deferred revenue	54,931	50,623
Accrued compensation and benefits	6,167	4,817
Other current liabilities	1,350	1,831
Total current liabilities	68,936	62,886
Deferred revenue	558	1,767
Notes payable	'	2,418
Other liabilities	1,351	2,327
Total liabilities	70,845	69,398
Commitments and contingencies (see Note 6)	'	'
Stockholders' equity (deficit):	'	'
Preferred stock, value	'	'
Common stock, par value $0.000005 per share - 500,000 shares authorized; 22,113 and 49,381 issued and outstanding as of December 31, 2013 and September 30, 2014, respectively	'	'
Additional paid-in capital	220,636	9,407
Accumulated deficit	-113,224	-83,243
Accumulated other comprehensive loss	-86	-120
Total stockholders' equity (deficit)	107,326	-6,263
Total liabilities and stockholders' equity (deficit)	178,171	63,135
Series A Convertible Preferred Stock [Member]	'	'
Stockholders' equity (deficit):	'	'
Preferred stock, value	'	1,466
Series B Convertible Preferred Stock [Member]	'	'
Stockholders' equity (deficit):	'	'
Preferred stock, value	'	16,355
Series C Convertible Preferred Stock [Member]	'	'
Stockholders' equity (deficit):	'	'
Preferred stock, value	'	49,872
Convertible Preferred Stock [Member]	'	'
Stockholders' equity (deficit):	'	'
Preferred stock, value	'	$67,693

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Allowance for doubtful accounts	$0	$361
Preferred stock, par value	$0.00	'
Preferred stock, shares authorized	25,000,000	'
Preferred stock, shares issued	0	'
Preferred stock, shares outstanding	0	'
Common stock, par value	$0.00	$0.00
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	49,381,000	22,113,000
Common stock, shares outstanding	49,381,000	22,113,000
Series A Convertible Preferred Stock [Member]	'	'
Preferred stock, par value	'	$0.00
Preferred stock, shares authorized	'	5,378,000
Preferred stock, shares issued	'	5,378,000
Preferred stock, shares outstanding	'	5,378,000
Preferred stock, liquidation preference	'	1,545
Series B Convertible Preferred Stock [Member]	'	'
Preferred stock, par value	'	$0.00
Preferred stock, shares authorized	'	8,376,000
Preferred stock, shares issued	'	8,251,000
Preferred stock, shares outstanding	'	8,251,000
Preferred stock, liquidation preference	'	16,448
Series C Convertible Preferred Stock [Member]	'	'
Preferred stock, par value	'	$0.00
Preferred stock, shares authorized	'	5,674,000
Preferred stock, shares issued	'	5,618,000
Preferred stock, shares outstanding	'	5,618,000
Preferred stock, liquidation preference	'	$50,000

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Operations (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Statement [Abstract]	'	'	'	'
Revenue	$33,774	$22,491	$93,594	$62,743
Cost of revenue	11,212	7,970	31,920	23,239
Gross profit	22,562	14,521	61,674	39,504
Operating expenses:	'	'	'	'
Sales and marketing	14,580	8,391	43,958	22,615
Research and development	11,177	7,821	34,131	19,666
General and administrative	4,241	1,886	13,010	4,948
Total operating expenses	29,998	18,098	91,099	47,229
Operating loss	-7,436	-3,577	-29,425	-7,725
Other income (expense):	'	'	'	'
Gain (loss) on foreign currency	-853	370	-691	-30
Interest expense	-14	-61	-99	-122
Other, net	144	84	287	17
Loss before income taxes	-8,159	-3,184	-29,928	-7,860
Provision for (benefit from) income taxes	37	-9	53	24
Net loss	($8,196)	($3,175)	($29,981)	($7,884)
Weighted-average common stock outstanding	'	'	'	'
Basic and diluted	49,091	21,303	39,253	20,959
Net loss per share:	'	'	'	'
Basic and diluted	($0.17)	($0.15)	($0.76)	($0.38)

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Loss (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]	'	'	'	'
Net loss	($8,196)	($3,175)	($29,981)	($7,884)
Other comprehensive income (loss)	'	'	'	'
Foreign currency translation	-89	58	-38	-16
Unrealized gain (loss) on hedge transactions, net	31	-75	72	-18
Total other comprehensive income (loss)	-58	-17	34	-34
Total comprehensive loss	($8,254)	($3,192)	($29,947)	($7,918)

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Stockholders' Equity (USD $)

Total

IPO [Member]

Convertible Preferred Stock [Member]

Convertible Preferred Stock [Member]

Convertible Preferred Stock [Member]

Convertible Preferred Stock [Member]

Convertible Preferred Stock [Member]

Convertible Preferred Stock [Member]

Common Stock [Member]

Common Stock [Member]

Additional Paid-in Capital [Member]

Additional Paid-in Capital [Member]

Accumulated Deficit [Member]

Accumulated Other Comprehensive Loss [Member]

In Thousands, except Share data

USD ($)

USD ($)

Series A Convertible Preferred Stock [Member]

Series B Convertible Preferred Stock [Member]

Series C Convertible Preferred Stock [Member]

IPO [Member]

IPO [Member]

IPO [Member]

IPO [Member]

USD ($)

IPO [Member]

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Series A Convertible Preferred Stock [Member]

Series B Convertible Preferred Stock [Member]

Series C Convertible Preferred Stock [Member]

USD ($)

USD ($)

USD ($)

USD ($)

Beginning Balance at Dec. 31, 2013

($6,263)

'

$1,466

$16,355

$49,872

'

'

'

'

'

$9,407

'

($83,243)

($120)

Beginning Balance, Shares at Dec. 31, 2013

'

'

5,378,000

8,251,000

5,618,000

'

'

'

22,113,000

'

'

'

'

'

Issuance of common stock

1,777

121,809

'

'

'

'

'

'

'

'

1,777

121,809

'

'

Issuance of common stock, Shares

'

'

'

'

'

'

'

'

849,000

7,015,000

'

'

'

'

Vesting of common stock subject to repurchase

682

'

'

'

'

'

'

'

'

'

682

'

'

'

Conversion of convertible preferred stock into common stock

'

'

'

'

'

-1,466

-16,355

-49,872

'

'

'

67,693

'

'

Vesting of common stock subject to repurchase, Shares

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Conversion of convertible preferred stock into common stock, Shares

'

'

'

'

'

-5,378,000

-8,251,000

-5,618,000

'

19,246,000

'

'

'

'

Stock-based compensation

16,272

'

'

'

'

'

'

'

'

'

16,272

'

'

'

Conversion of convertible debt into common stock

'

2,996

'

'

'

'

'

'

'

'

'

2,996

'

'

Foreign currency translation

-38

'

'

'

'

'

'

'

'

'

'

'

'

-38

Conversion of convertible debt into common stock, Shares

'

'

'

'

'

'

'

'

'

158,000

'

'

'

'

Unrealized gain on hedge transactions, net

72

'

'

'

'

'

'

'

'

'

'

'

'

72

Net loss

-29,981

'

'

'

'

'

'

'

'

'

'

'

-29,981

'

Ending Balance at Sep. 30, 2014

$107,326

'

'

'

'

'

'

'

'

'

$220,636

'

($113,224)

($86)

Ending Balance, Shares at Sep. 30, 2014

'

'

'

'

'

'

'

'

49,381,000

'

'

'

'

'

Condensed_Consolidated_Stateme3

Condensed Consolidated Statements of Cash Flows (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Operating Activities	'	'
Net loss	($29,981)	($7,884)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:	'	'
Depreciation and amortization	4,841	2,779
Stock-based compensation expense	15,425	1,920
Non-cash interest expense	51	109
Asset impairment	82	'
Other	263	59
Changes in operating assets and liabilities:	'	'
Accounts receivable	-1,102	-6,999
Prepaid expenses and other current assets	-1,236	-339
Other assets	62	-571
Accounts payable	-215	547
Accrued expenses	1,256	1,495
Accrued compensation and benefits	1,363	446
Deferred revenue	2,755	14,779
Other liabilities	-319	-360
Net cash provided by (used in) operating activities	-6,755	5,981
Investing Activities	'	'
Additions to property and equipment	-8,081	-5,660
Net cash used in investing activities	-8,081	-5,660
Financing Activities	'	'
Proceeds from issuance of common stock	1,777	2,548
Proceeds from initial public offering, net of underwriting discounts and commissions	123,955	'
Issuance of notes payable	'	2,500
Payment of offering costs	-1,687	'
Principal payments on capital lease obligations	-358	-24
Net cash provided by financing activities	123,687	5,024
Effect of exchange rate changes on cash and cash equivalents	-105	-11
Net increase in cash and cash equivalents	108,746	5,334
Cash and cash equivalents, beginning of period	28,819	24,597
Cash and cash equivalents, end of period	137,565	29,931
Supplemental cash flow information	'	'
Cash paid for income taxes, net of tax refunds	7	22
Cash paid for interest	52	8
Supplemental disclosure of non-cash investing and financing activities	'	'
Assets acquired under capital leases	'	918
Accrued property and equipment purchases	203	78
Capitalized stock-based compensation	847	91
Vesting of common stock subject to repurchase	682	271
Accrued deferred offering costs	185	'
Conversion of convertible preferred stock into common stock	67,693	'
Conversion of convertible debt into common stock	$2,996	'

Company_Overview

Company Overview	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
Company Overview	'
	1. Company Overview
	Opower, Inc. (“Opower” or “the Company”) is a cloud-based software provider to the utility industry. Utilities use the Company’s software platform to deliver key customer-facing applications that reduce energy demand and improve customer perception of the utility. The Company’s software analyzes energy data and presents personalized insights to consumers in order to motivate reductions in energy consumption.

Initial_Public_Offering

Initial Public Offering	9 Months Ended
	Sep. 30, 2014
Text Block [Abstract]	'
Initial Public Offering	'
	2. Initial Public Offering
	In April 2014, the Company closed its initial public offering of its common stock (the “IPO”) whereby 7,015,000 shares of common stock were sold to the public, including 915,000 shares sold pursuant to the underwriters’ option to purchase additional shares, at a price of $19.00 per share. The Company’s shares are traded on the New York Stock Exchange under the symbol “OPWR”. The Company received aggregate proceeds of $121.8 million from the IPO, net of underwriters’ discounts and commissions and offering expenses of $2.1 million. Upon the closing of the IPO, all shares of the Company’s outstanding convertible preferred stock automatically converted into 19,246,714 shares of common stock, and the Company’s subordinated convertible promissory note automatically converted into 157,664 shares of common stock. Offering expenses of $0.8 million were recorded in other assets on the condensed consolidated balance sheets as of December 31, 2013 and $2.1 million were reclassified to additional paid-in capital in connection with the IPO.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
Summary of Significant Accounting Policies	'
	3. Summary of Significant Accounting Policies
	Basis of Presentation
	The accompanying unaudited condensed consolidated financial statements include the accounts of Opower and its wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation. Certain prior period amounts have been reclassified to conform to current period presentation.
	These unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial reporting and the applicable rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to those rules and regulations. Therefore, these interim financial statements should be read in conjunction with the audited consolidated financial statements and related notes contained in the Company’s Registration Statement on Form S-1 (Registration No. 333-194264) filed with the SEC on March 3, 2014, as amended on March 24, 2014 (the “Registration Statement”) and declared effective by the SEC on April 3, 2014. There have been no changes to the Company’s significant accounting policies described in the Registration Statement that have had a material impact on our condensed consolidated financial statements and related notes.
	In the opinion of our management, all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation of the Company’s results of operations, financial position and cash flows have been included. The results for interim periods are not necessarily indicative of results that may be expected for any other interim period or for the full year. The year-end condensed balance sheet data was derived from the audited financial statements, but does not include all disclosures required by GAAP.
	Reclassifications and Adjustments
	During the first quarter of 2014, the Company updated its methodology for allocating certain general and administrative costs to more closely align these costs to the functional departments consuming the related services. As a result, certain prior period costs have been reclassified from general and administrative expenses to cost of revenue, sales and marketing expenses, and research and development expenses primarily based on the headcount in each of these functional areas. The reclassifications for the three months ended September 30, 2013 reduced general and administrative expenses by $1.4 million and increased cost of revenue, sales and marketing expenses, and research and development expenses by $0.2 million, $0.6 million and $0.6 million, respectively. The reclassifications for the nine months ended September 30, 2013 reduced general and administrative expenses by $3.5 million and increased cost of revenue, sales and marketing expenses, and research and development expenses by $0.4 million, $1.6 million, and $1.5 million, respectively. These reclassifications had no effect on previously reported operating loss, net loss or cash flows.
	During the first quarter of 2014, the Company recorded adjustments related to prior periods which increased revenue by $0.3 million for the nine months ended September 30, 2014, and increased gains on foreign currency by $0.2 million for the nine months ended September 30, 2014. The Company has concluded that these changes do not have a material effect on the reported results of operations for the nine months ended September 30, 2014 after consideration of quantitative and qualitative factors. The impact to all prior interim and annual periods was also not material.
	Use of Estimates
	The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in these consolidated financial statements and accompanying notes. Significant items subject to such estimates include revenue recognition, the useful lives and recoverability of property and equipment, stock-based compensation and income taxes. Actual results could differ significantly from those estimates.
	Concentration of Credit Risk
	Financial instruments that potentially subject the Company to significant concentration of credit risk consist primarily of cash, cash equivalents and accounts receivable. The Company maintains the majority of its cash and cash equivalents with one financial institution, which management believes to be financially sound and with minimal credit risk. The Company’s deposits periodically exceed amounts guaranteed by the Federal Deposit Insurance Corporation.
	To manage accounts receivable risk, the Company monitors and evaluates the credit worthiness of its customers and maintains an allowance for doubtful accounts as deemed necessary. Collection efforts from long-established utilities have been historically successful, so the Company believes credit risk to be low.
	The following table summarizes those customers who represented at least 10% of revenue or accounts receivable for the periods presented:
			Revenue			Revenue		Accounts Receivable
			Three Months Ended			Nine Months Ended		December 31,	September 30,
			September 30,			September 30,		2013	2014
			2013		2014	2013	2014
	Customer A		16%		15%	12%	12%	*	*
	Customer B		14%		10%	14%	10%	*	*
	Customer C		13%		10%	14%	*	22%	23%
	Customer D		*		*	*	*	*	11%
	Customer E		*		*	*	*	12%	*
	Customer F		*		*	*	*	10%	*
	*	=xA0;Represented less than 10%
	Fair Value Measurement
	The Company applies fair value accounting for all financial assets and liabilities that are reported at fair value in the financial statements on a recurring basis. Fair value is defined as the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The accounting guidance establishes a defined three-tier hierarchy to classify and disclose the fair value of assets and liabilities on both the date of their initial measurement as well as all subsequent periods. The hierarchy prioritizes the inputs used to measure fair value by the lowest level of input that is available and significant to the fair value measurement. The three levels are described as follows:
		•		Level 1: Observable inputs. Quoted prices in active markets for identical assets and liabilities;
		•		Level 2: Observable inputs other than the quoted price. Includes quoted prices for similar instruments, quoted prices for identical or similar instruments in inactive markets and amounts derived from valuation models where all significant inputs are observable in active markets; and
		•		Level 3: Unobservable inputs. Includes amounts derived from valuation models where one or more significant inputs are unobservable and require the Company to develop relevant assumptions.
	The Company evaluates its financial assets and liabilities subject to fair value measurements on a recurring basis to determine the appropriate level of classification as of each reporting period.
	Derivative Financial Instruments
	The Company has entered into derivative contracts to reduce the risk that foreign currency exchange rate fluctuations will adversely affect its cash flows and earnings. These derivative contracts are designed to be hedging instruments, meaning any changes in cash flow are expected to be completely offset by the hedging derivative due to the fact that the critical terms of the forward contracts and forecasted sales transactions are aligned. The Company’s unsettled foreign currency derivative contracts are recorded at their fair value as either assets or liabilities on the consolidated balance sheets and are marked-to-market at the end of each reporting period. Unrealized gains and losses from the cash flow hedges are recognized as part of other comprehensive income to the extent the hedge is effective. These gains and losses are recognized in the consolidated statements of operations in revenue once the forward contracts are settled and the forecasted transaction they are designed to hedge has impacted the statements of operations. Any portions of the hedging arrangement deemed to be ineffective are recognized in the consolidated statements of operations immediately.
	In March 2013, the Company entered into a convertible debt agreement that contained certain conversion features and a change in control premium that were deemed to represent derivative financial instruments valued collectively. The fair value of the derivative was measured at inception and recorded as a noncurrent liability on the consolidated balance sheet. This derivative financial instrument was re-measured and marked-to-market at the end of each reporting period, and changes in fair value from period to period were recognized within other income (expense), net on the statements of operations. Upon the closing of the IPO, the Company’s convertible debt automatically converted into common stock.
	Comprehensive Loss
	Comprehensive loss consists of two components, net loss and other comprehensive income (loss). Other comprehensive income (loss) refers to gains and losses that are recorded as a separate element of stockholders’ equity (deficit) and are excluded from net loss. The Company’s other comprehensive income (loss) is comprised of foreign currency translation adjustments and unrealized gains or losses on hedge transactions.
	Operating Segment
	Operating segments are defined as components of a business that can earn revenue and incur expenses for which discrete financial information is available that is evaluated on a regular basis by the chief operating decision maker (“CODM”) to decide how to allocate resources and assess performance. The Company’s CODM, the Chief Executive Officer, reviews consolidated results of operations to make decisions, therefore the Company views its operations and manages its business as one operating segment.
	Recently Issued Accounting Standards
	In July 2013, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists. This guidance states that a liability related to an unrecognized tax benefit should be offset against a deferred tax asset for a net operating loss carryforward, a similar tax loss or a tax credit carryforward if such settlement is required or expected in the event the uncertain tax position is disallowed. The new guidance is effective on a prospective basis for annual and interim periods beginning after December 15, 2013, but early adoption and retrospective application are permitted. The Company adopted the guidance effective January 1, 2014 and it did not have a material impact on its consolidated financial statements.
	In April 2014, the FASB issued ASU 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360). The ASU raises the threshold for a disposal to qualify as discontinued operations and requires new disclosures for individually significant disposal transactions that do not meet the definition of a discontinued operation. Under the new standard, companies report discontinued operations when they have a disposal that represents a strategic shift that has or will have a major impact on operations or financial results. The ASU will be applied prospectively and is effective for annual periods, and interim periods within those years, beginning after December 15, 2014 with early adoption permitted. The Company does not currently expect the adoption of this guidance to have a material impact on its consolidated financial statements
	In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers, which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The ASU will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The new standard is effective for the Company on January 1, 2017. Early application is not permitted. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures. The Company has not yet selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting.

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	4. Fair Value Measurements
	The following table summarizes the Company’s assets and liabilities measured at fair value on a recurring basis as of December 31, 2013 and September 30, 2014 (in thousands):
			December 31, 2013												September 30, 2014
			Fair Value			Level 1			Level 2			Level 3			Fair Value			Level 1		Level 2			Level 3
	Assets:
	Cash equivalents (1):
	Money market funds (2)		$	15,511		$	15,511			—			—		$	117,051		$	117,051		—			—
	Total		$	15,511		$	15,511			—			—		$	117,051		$	117,051		—			—
	Liabilities:
	Foreign currency derivative contracts		$	(41	)	$	—		$	(41	)	$	—			(4	)	$	—	$	(4	)	$	—
	Convertible debt derivative			(388	)		—			—			(388	)		—			—		—			—
	Total		$	(429	)	$	—		$	(41	)	$	(388	)	$	(4	)	$	—	$	(4	)	$	—
	(1)	Included in cash and cash equivalents on the condensed consolidated balance sheets.
	(2)	Money market funds associated with the Company’s overnight investment sweep account.
	The foreign currency derivative contracts are classified within Level 2 because they are valued using alternative pricing sources and models utilizing observable market inputs for similar instruments. The fair value measurement of the convertible debt derivative was determined through the use of a probability-weighted expected return model (“PWERM”). The PWERM considers the timing and cash flows related to each potential conversion scenario and applies a percentage likelihood of occurrence in order to develop an estimated fair value for the instrument as a whole. This valuation methodology is based on unobservable estimates and judgments, and therefore is classified as a Level 3 fair value measurement.
	The following table presents a reconciliation of the convertible debt derivative instrument measured at fair value using significant unobservable inputs, and the amount of gain (loss) recorded in the Company’s condensed consolidated statements of operations as a result of changes in fair value (in thousands):
			Nine Months Ended
			September 30,
			2013			2014
	Convertible debt derivative
	Balance, beginning of period		$	—		$	(388	)
	Initial valuation on date of issuance			(241	)		—
	Revaluation			(77	)		30
	Conversion of debt			—			358
	Balance, end of period		$	(318	)	$	—
	All of the Company’s derivative financial instruments are classified on the consolidated balance sheets as other current liabilities and other liabilities, and none are designated for trading or speculative purposes.
	Other Fair Value Disclosures
	The fair value of the Company’s notes payable was determined based on a discounted cash flow analysis using Level 2 inputs based on quoted market prices for similar instruments that are not active. As of December 31, 2013, the estimated fair value of the notes payable approximated its carrying value of $2.4 million.

Property_and_Equipment

Property and Equipment	9 Months Ended
	Sep. 30, 2014
Property, Plant and Equipment [Abstract]	'
Property and Equipment	'
	5. Property and Equipment
	Property and equipment consisted of the following (in thousands):
		December 31,			September 30,
		2013			2014
	Equipment	$	5,034		$	5,940
	Software		8,948			16,293
	Furniture and fixtures		306			333
	Leasehold improvements		2,038			2,617
	Total property and equipment	$	16,326		$	25,183
	Accumulated depreciation and amortization		(5,513	)		(10,166	)
	Total property and equipment, net	$	10,813		$	15,017
	As of December 31, 2013 and September 30, 2014, the gross carrying amount of property and equipment includes computer equipment under capital leases with a cost basis of $1.4 million and $1.4 million, respectively. Accumulated depreciation related to this computer equipment was $0.2 million and $0.5 million as of December 31, 2013 and September 30, 2014, respectively. Interest expense for the three months and nine months ended September 30, 2013 and 2014 was immaterial. As of December 31, 2013 and September 30, 2014, the total capital lease obligation was $1.3 million and $0.9 million, respectively, and recorded on the consolidated balance sheets as other current liabilities and other liabilities.
	Capitalized internal-use software costs are also included in property and equipment. During the three months ended September 30, 2013 and 2014, the Company capitalized $1.4 million and $3.2 million of these software development costs, respectively. During the nine months ended September 30, 2013 and 2014, the Company capitalized $4.9 million and $7.1 million of these software development costs, respectively. The net book value of capitalized internal use software was $6.4 million and $10.4 million as of December 31, 2013 and September 30, 2014, respectively. Amortization expense related to capitalized internal-use software was $0.7 million and $1.2 million for the three months ended September 30, 2013 and 2014, respectively, and $1.7 million and $3.0 million for the nine months ended September 30, 2013 and 2014, respectively.
	The following table represents a detailed breakout of depreciation and amortization expense as recorded in the condensed consolidated statements of operations (in thousands):
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2013			2014			2013		2014
	Cost of revenue	$	500		$	782		$	1,094	$	2,030
	Sales and marketing		101			123			211		270
	Research and development		532			898			1,299		2,282
	General and administrative		25			49			175		259
	Total	$	1,158		$	1,852		$	2,779	$	4,841

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	6. Commitments and Contingencies
	Operating and Capital Leases
	The Company leases domestic office space in Arlington, Virginia and San Francisco, California, as well as international office space in Japan, Singapore and the United Kingdom. All leases are non-cancelable operating lease agreements that expire at various dates through 2016 and include renewal options.
	In June 2013, the Company entered into a master lease agreement with a financing company. The agreement allows for the Company to lease eligible equipment purchases. Each lease has a 36 month term, payable in equal monthly installments with the exception of the first and final payments which are prorated based on a midmonth convention. The Company has accounted for the leases under the master lease agreement as capital leases. The weighted-average interest rate implicit in the leases was 6%.
	Rent expense under operating leases was $0.9 million and $1.1 million for the three months ended September 30, 2013 and 2014, respectively, and $2.0 million and $3.3 million for the nine months ended September 30, 2013 and 2014, respectively.
	Letters of Credit
	As of December 31, 2013 and September 30, 2014, the Company had outstanding letters of credit totaling $1.1 million in connection with securing its leased office space. The outstanding amounts for the Arlington and San Francisco offices are $1.0 million and $0.1 million, respectively, and both letters of credit remain outstanding as of September 30, 2014.
	Contingencies and Indemnifications
	In the normal course of business, the Company enters into contracts and agreements that may contain representations and warranties and provide for general indemnifications. The Company’s exposure under these agreements is unknown because it involves claims that may be made in the future, but have not yet been made. The Company has not paid any claims or been required to defend any actions related to indemnification obligations. However, the Company could incur costs in the future as a result of indemnification obligations.
	In accordance with its bylaws, the Company has indemnification obligations to its officers, directors, employees and agents (other than directors and officers) for certain events or occurrences, subject to certain limits, while they are serving at the Company’s request in such capacity. There have been no claims, and the Company has a director and officer insurance policy that enables it to recover a portion of any future claims.

Stockholders_Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2014
Equity [Abstract]	'
Stockholders' Equity	'
	7. Stockholders’ Equity
	Common Stock
	The Company is authorized to grant the right to purchase common stock subject to specific conditions and restrictions, otherwise referred to as “restricted stock.” In December 2011, the Company sold 0.4 million shares of restricted stock to its Chief Financial Officer at $2.09 per share, the fair value of the Company’s common stock at that time, for a total purchase price of $0.9 million. The restricted stock vested over a three year period; 36% vested after the first year and the remaining shares vested ratably over the following two years.
	The following table summarizes the activity of the Company’s outstanding restricted stock for the nine months ended September 30, 2014 (in thousands, expect per share amounts):
		Restricted			Weighted-
		Shares			Average
					Grant Date
					Fair Value
	Balance as of December 31, 2013		113		$	2.09
	Vested		(113	)		2.09
	Balance as of September 30, 2014		—
	In the event of a termination of services for any reason, any unvested shares of restricted stock were subject to a repurchase option by the Company at the original purchase price. The initial funds received for the restricted common stock were recorded as a liability and subsequently reclassified to equity over time as the restricted stock vests and they are released from the repurchase option. The total repurchase option liability related to restricted stock was $0.2 million as of December 31, 2013.
	Accumulated Other Comprehensive Loss
	Other comprehensive loss is comprised of certain gains and losses that are excluded from net income under GAAP and instead recorded as a separate element of stockholders’ equity (deficit). The Company’s other comprehensive loss consists of foreign currency translation adjustments resulting from the translation of the Company’s foreign subsidiaries whose functional currency is their respective local currency, as well as any unrealized gains or losses on the Company’s unsettled foreign currency derivative contracts.
	The following table summarizes the activity for each component of accumulated other comprehensive loss (in thousands):
		Foreign			Foreign			Accumulated
		currency			currency			other
		translation			derivative			comprehensive
					instruments			loss
	Balance as of December 31, 2013	$	(6	)	$	(114	)	$	(120	)
	Other comprehensive income (loss) before reclassifications		(38	)		10			(28	)
	Reclassifications to net income		—			62			62
	Other comprehensive income (loss)		(38	)		72			34
	Balance as of September 30, 2014	$	(44	)	$	(42	)	$	(86	)
	Gains and losses on cash flow hedges are recognized in the consolidated statements of operations in revenue.

StockBased_Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Stock-Based Compensation	'
	8. Stock-Based Compensation
	Stock Option Activity
	A summary of stock option activity for the nine months ended September 30, 2014 is summarized in the following table (in thousands, except time period and per share amounts):
			Options			Weighted-		Weighted-		Aggregate
			Outstanding			Average		Average		Intrinsic
						Exercise		Remaining		Value(1)
						Price		Contractual
								Term
								(Years)
	Balance at December 31, 2013			7,790		$	3.83		7.6	$	98,814
	Granted			50			18
	Exercised			(836	)		2.12
	Forfeited			(251	)		3.72
	Balance at September 30, 2014			6,753		$	4.16		7.5	$	99,299
	Vested and expected to vest after September 30, 2014			6,572		$	4.06		7.4	$	97,264
	Exercisable at September 30, 2014			4,627		$	3.46		7.1	$	71,264
	(1)	Aggregate intrinsic value represents the difference between the fair value of the underlying common stock and the exercise price of outstanding, in-the-money stock options.
	The 2007 Stock Plan allows for grants of immediately exercisable stock options. The Company has the right to purchase any unvested, but issued common shares at the original exercise price during the repurchase period following an employee’s termination. The consideration received for an exercise of an unvested option is considered to be a deposit of the exercise price. The related dollar amount is recorded as other current liabilities and other liabilities on the Company’s consolidated balance sheets and will be reclassified to equity as the Company’s repurchase right lapses. As of December 31, 2013 and September 30, 2014, unvested stock options subject to repurchase were 0.3 million and 0.2 million, respectively, at an aggregate exercise price of $0.9 million and $0.5 million, respectively.
	The following table summarizes additional information on stock option grants, vesting and exercises (in thousands):
			Three Months Ended					Nine Months Ended
			September 30,					September 30,
			2013			2014		2013		2014
	Total fair value of stock options granted		$	16,087		$	—	$	17,879	$	434
	Total fair value of shares vested			466			1,869		1,160		4,689
	Total intrinsic value of stock options exercised			2,765			2,897		5,567		13,012
	Cash received from stock options exercised			948			327		2,548		1,777
	Restricted Stock Unit Activity
	A summary of restricted stock unit (“RSU”) activity for the nine months ended September 30, 2014 is summarized in the following table (in thousands, except per share amounts):
			Shares			Weighted-
						Average
						Grant Date
						Fair Value
	Balance as of December 31, 2013			1,093		$	15.48
	Granted			1,270			17.3
	Released			(13	)		16.65
	Forfeited			(198	)		16.32
	Balance as of September 30, 2014			2,152		$	16.49
	Subsequent to September 30, 2014, the Company granted 1.1 million RSUs with an aggregate grant-date fair value of $18.6 million.
	Stock-Based Compensation Expense
	Stock-based compensation expense is included in the condensed consolidated statements of operations within the following line items (in thousands):
			Three Months Ended					Nine Months Ended
			September 30,					September 30,
			2013			2014		2013		2014
	Cost of revenue		$	67		$	305	$	133		918
	Sales and marketing			492			2,019		748		6,994
	Research and development			328			1,195		677		4,088
	General and administrative			291			968		362		3,425
	Total		$	1,178		$	4,487	$	1,920	$	15,425
	As of September 30, 2014, there was $15.1 million of unrecognized stock-based compensation expense related to unvested stock options granted to employees and non-employee service providers, which is expected to be recognized over a weighted-average period of 2.9 years. The total unrecognized stock-based compensation expense relating to these RSUs was $20.9 million as of September 30, 2014, which is expected to be recognized over a weighted-average period of 2.7 years. Total capitalized stock-based compensation expense for the three months and nine months ended September 30, 2014 was $0.4 million and $0.8 million, respectively.

Income_Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2014
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	9. Income Taxes
	For the three months and nine months ended September 30, 2013 and 2014, the income tax provision for continuing operations is composed of state tax expense and foreign tax expense for the Company’s consolidated international subsidiaries.
	The Company has evaluated the positive and negative evidence bearing upon the realizability of its deferred tax assets. Based on the Company’s limited operating history and cumulative operating losses to date, management believes that it is more likely than not that the Company’s deferred tax assets would not be fully realized. Accordingly, the deferred tax assets have been fully reserved at December 31, 2013 and September 30, 2014.
	To date, there have been no tax benefits recognized related to uncertain tax positions. The Company does not anticipate a material change in the unrecognized tax benefits in the next twelve months.

Net_Income_Loss_Per_Share

Net Income (Loss) Per Share	9 Months Ended
	Sep. 30, 2014
Earnings Per Share [Abstract]	'
Net Income (Loss) Per Share	'
	10. Net Income (Loss) Per Share
	The Company computes net loss per share of common stock in conformity with the two-class method required for participating securities. The Company considered all series of convertible preferred stock to be participating securities, as the holders of the preferred stock were entitled to receive a non-cumulative dividend on a pari-passu basis in the event that a dividend is paid on common stock. Upon the closing of the IPO, all shares of the Company’s outstanding convertible preferred stock automatically converted into shares of common stock. The Company also considers unvested restricted common stock and the shares issued upon the early exercise of stock options that are subject to repurchase to be participating securities, because holders of such shares have dividend rights in the event a dividend is paid on common stock. The holders of all series of convertible preferred stock, prior to their conversion upon the closing of the IPO, and the holders of early exercised shares subject to repurchase do not have a contractual obligation to share in the losses of the Company. As such, the Company’s net losses for the three months and nine months ended September 30, 2013 and 2014 were not allocated to these participating securities.
	The following table summarizes the calculation of the Company’s basic and diluted net loss per share under the two-class method attributable to common stockholders for the three months and nine months ended September 30, 2013 and 2014 (in thousands, except per share amounts):
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2013			2014			2013			2014
	Numerator:
	Net loss	$	(3,175	)	$	(8,196	)	$	(7,884	)	$	(29,981	)
	Non-cumulative dividends to preferred stockholders		—			—			—			—
	Net loss attributable to common stockholders	$	(3,175	)	$	(8,196	)	$	(7,884	)	$	(29,981	)
	Denominator:
	Weighted-average common stock outstanding, basic		21,303			49,091			20,959			39,253
	Effect of potentially dilutive stock options and restricted stock		—			—			—			—
	Weighted-average common stock outstanding, diluted		21,303			49,091			20,959			39,253
	Net loss per share, basic and diluted	$	(0.15	)	$	(0.17	)	$	(0.38	)	$	(0.76	)
	Anti-Dilutive Shares Excluded
	The following potential shares were excluded from the calculation of diluted net loss per share attributable to common stockholders because their effect would have been anti-dilutive for the periods presented (in thousands):
		September 30,
		2013			2014
	Convertible preferred stock		19,247			—
	Stock options		7,634			6,753
	Restricted stock units		—			2,152
	Common stock subject to repurchase		465			201
			27,346			9,106
	In addition, for periods prior to the IPO, the Company has also excluded the convertible preferred stock and convertible note payable from the calculation of diluted net loss per share attributable to common stockholders because the conversion was contingent on future events.

Geographic_Information

Geographic Information	9 Months Ended
	Sep. 30, 2014
Text Block [Abstract]	'
Geographic Information	'
	11. Geographic Information
	Revenue generated for customers located in the United States was approximately 91% and 84% of revenue for the three months ended September 30, 2013 and 2014, respectively, and approximately 92% and 85% of revenue for the nine months ended September 30, 2013 and 2014, respectively.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
Basis of Presentation	'
	Basis of Presentation
	The accompanying unaudited condensed consolidated financial statements include the accounts of Opower and its wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation. Certain prior period amounts have been reclassified to conform to current period presentation.
	These unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial reporting and the applicable rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to those rules and regulations. Therefore, these interim financial statements should be read in conjunction with the audited consolidated financial statements and related notes contained in the Company’s Registration Statement on Form S-1 (Registration No. 333-194264) filed with the SEC on March 3, 2014, as amended on March 24, 2014 (the “Registration Statement”) and declared effective by the SEC on April 3, 2014. There have been no changes to the Company’s significant accounting policies described in the Registration Statement that have had a material impact on our condensed consolidated financial statements and related notes.
	In the opinion of our management, all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation of the Company’s results of operations, financial position and cash flows have been included. The results for interim periods are not necessarily indicative of results that may be expected for any other interim period or for the full year. The year-end condensed balance sheet data was derived from the audited financial statements, but does not include all disclosures required by GAAP.
Reclassifications and Adjustments	'
	Reclassifications and Adjustments
	During the first quarter of 2014, the Company updated its methodology for allocating certain general and administrative costs to more closely align these costs to the functional departments consuming the related services. As a result, certain prior period costs have been reclassified from general and administrative expenses to cost of revenue, sales and marketing expenses, and research and development expenses primarily based on the headcount in each of these functional areas. The reclassifications for the three months ended September 30, 2013 reduced general and administrative expenses by $1.4 million and increased cost of revenue, sales and marketing expenses, and research and development expenses by $0.2 million, $0.6 million and $0.6 million, respectively. The reclassifications for the nine months ended September 30, 2013 reduced general and administrative expenses by $3.5 million and increased cost of revenue, sales and marketing expenses, and research and development expenses by $0.4 million, $1.6 million, and $1.5 million, respectively. These reclassifications had no effect on previously reported operating loss, net loss or cash flows.
	During the first quarter of 2014, the Company recorded adjustments related to prior periods which increased revenue by $0.3 million for the nine months ended September 30, 2014, and increased gains on foreign currency by $0.2 million for the nine months ended September 30, 2014. The Company has concluded that these changes do not have a material effect on the reported results of operations for the nine months ended September 30, 2014 after consideration of quantitative and qualitative factors. The impact to all prior interim and annual periods was also not material.
Use of Estimates	'
	Use of Estimates
	The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in these consolidated financial statements and accompanying notes. Significant items subject to such estimates include revenue recognition, the useful lives and recoverability of property and equipment, stock-based compensation and income taxes. Actual results could differ significantly from those estimates.
Concentration of Credit Risk	'
	Concentration of Credit Risk
	Financial instruments that potentially subject the Company to significant concentration of credit risk consist primarily of cash, cash equivalents and accounts receivable. The Company maintains the majority of its cash and cash equivalents with one financial institution, which management believes to be financially sound and with minimal credit risk. The Company’s deposits periodically exceed amounts guaranteed by the Federal Deposit Insurance Corporation.
	To manage accounts receivable risk, the Company monitors and evaluates the credit worthiness of its customers and maintains an allowance for doubtful accounts as deemed necessary. Collection efforts from long-established utilities have been historically successful, so the Company believes credit risk to be low.
Fair Value Measurement	'
	Fair Value Measurement
	The Company applies fair value accounting for all financial assets and liabilities that are reported at fair value in the financial statements on a recurring basis. Fair value is defined as the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The accounting guidance establishes a defined three-tier hierarchy to classify and disclose the fair value of assets and liabilities on both the date of their initial measurement as well as all subsequent periods. The hierarchy prioritizes the inputs used to measure fair value by the lowest level of input that is available and significant to the fair value measurement. The three levels are described as follows:
		•	Level 1: Observable inputs. Quoted prices in active markets for identical assets and liabilities;
		•	Level 2: Observable inputs other than the quoted price. Includes quoted prices for similar instruments, quoted prices for identical or similar instruments in inactive markets and amounts derived from valuation models where all significant inputs are observable in active markets; and
		•	Level 3: Unobservable inputs. Includes amounts derived from valuation models where one or more significant inputs are unobservable and require the Company to develop relevant assumptions.
	The Company evaluates its financial assets and liabilities subject to fair value measurements on a recurring basis to determine the appropriate level of classification as of each reporting period.
Derivative Financial Instruments	'
	Derivative Financial Instruments
	The Company has entered into derivative contracts to reduce the risk that foreign currency exchange rate fluctuations will adversely affect its cash flows and earnings. These derivative contracts are designed to be hedging instruments, meaning any changes in cash flow are expected to be completely offset by the hedging derivative due to the fact that the critical terms of the forward contracts and forecasted sales transactions are aligned. The Company’s unsettled foreign currency derivative contracts are recorded at their fair value as either assets or liabilities on the consolidated balance sheets and are marked-to-market at the end of each reporting period. Unrealized gains and losses from the cash flow hedges are recognized as part of other comprehensive income to the extent the hedge is effective. These gains and losses are recognized in the consolidated statements of operations in revenue once the forward contracts are settled and the forecasted transaction they are designed to hedge has impacted the statements of operations. Any portions of the hedging arrangement deemed to be ineffective are recognized in the consolidated statements of operations immediately.
	In March 2013, the Company entered into a convertible debt agreement that contained certain conversion features and a change in control premium that were deemed to represent derivative financial instruments valued collectively. The fair value of the derivative was measured at inception and recorded as a noncurrent liability on the consolidated balance sheet. This derivative financial instrument was re-measured and marked-to-market at the end of each reporting period, and changes in fair value from period to period were recognized within other income (expense), net on the statements of operations. Upon the closing of the IPO, the Company’s convertible debt automatically converted into common stock.
Comprehensive Loss	'
	Comprehensive Loss
	Comprehensive loss consists of two components, net loss and other comprehensive income (loss). Other comprehensive income (loss) refers to gains and losses that are recorded as a separate element of stockholders’ equity (deficit) and are excluded from net loss. The Company’s other comprehensive income (loss) is comprised of foreign currency translation adjustments and unrealized gains or losses on hedge transactions.
Operating Segment	'
	Operating Segment
	Operating segments are defined as components of a business that can earn revenue and incur expenses for which discrete financial information is available that is evaluated on a regular basis by the chief operating decision maker (“CODM”) to decide how to allocate resources and assess performance. The Company’s CODM, the Chief Executive Officer, reviews consolidated results of operations to make decisions, therefore the Company views its operations and manages its business as one operating segment.
Recently Issued Accounting Standards	'
	Recently Issued Accounting Standards
	In July 2013, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists. This guidance states that a liability related to an unrecognized tax benefit should be offset against a deferred tax asset for a net operating loss carryforward, a similar tax loss or a tax credit carryforward if such settlement is required or expected in the event the uncertain tax position is disallowed. The new guidance is effective on a prospective basis for annual and interim periods beginning after December 15, 2013, but early adoption and retrospective application are permitted. The Company adopted the guidance effective January 1, 2014 and it did not have a material impact on its consolidated financial statements.
	In April 2014, the FASB issued ASU 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360). The ASU raises the threshold for a disposal to qualify as discontinued operations and requires new disclosures for individually significant disposal transactions that do not meet the definition of a discontinued operation. Under the new standard, companies report discontinued operations when they have a disposal that represents a strategic shift that has or will have a major impact on operations or financial results. The ASU will be applied prospectively and is effective for annual periods, and interim periods within those years, beginning after December 15, 2014 with early adoption permitted. The Company does not currently expect the adoption of this guidance to have a material impact on its consolidated financial statements
	In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers, which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The ASU will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. The new standard is effective for the Company on January 1, 2017. Early application is not permitted. The standard permits the use of either the retrospective or cumulative effect transition method. The Company is evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures. The Company has not yet selected a transition method nor has it determined the effect of the standard on its ongoing financial reporting.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
Summary of Revenue or Accounts Receivable Percentage of Major Customers	'
	The following table summarizes those customers who represented at least 10% of revenue or accounts receivable for the periods presented:
			Revenue		Revenue		Accounts Receivable
			Three Months Ended		Nine Months Ended		December 31,	September 30,
			September 30,		September 30,		2013	2014
			2013	2014	2013	2014
	Customer A		16%	15%	12%	12%	*	*
	Customer B		14%	10%	14%	10%	*	*
	Customer C		13%	10%	14%	*	22%	23%
	Customer D		*	*	*	*	*	11%
	Customer E		*	*	*	*	12%	*
	Customer F		*	*	*	*	10%	*
	*	=xA0;Represented less than 10%

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Summary of Assets and Liabilities Measured at Fair Value on a Recurring Basis	'
	The following table summarizes the Company’s assets and liabilities measured at fair value on a recurring basis as of December 31, 2013 and September 30, 2014 (in thousands):
			December 31, 2013												September 30, 2014
			Fair Value			Level 1			Level 2			Level 3			Fair Value			Level 1		Level 2			Level 3
	Assets:
	Cash equivalents (1):
	Money market funds (2)		$	15,511		$	15,511			—			—		$	117,051		$	117,051		—			—
	Total		$	15,511		$	15,511			—			—		$	117,051		$	117,051		—			—
	Liabilities:
	Foreign currency derivative contracts		$	(41	)	$	—		$	(41	)	$	—			(4	)	$	—	$	(4	)	$	—
	Convertible debt derivative			(388	)		—			—			(388	)		—			—		—			—
	Total		$	(429	)	$	—		$	(41	)	$	(388	)	$	(4	)	$	—	$	(4	)	$	—
	(1)	Included in cash and cash equivalents on the condensed consolidated balance sheets.
	(2)	Money market funds associated with the Company’s overnight investment sweep account.
Reconciliation of Convertible Debt Derivative Instrument Measured at Fair Value	'
	The following table presents a reconciliation of the convertible debt derivative instrument measured at fair value using significant unobservable inputs, and the amount of gain (loss) recorded in the Company’s condensed consolidated statements of operations as a result of changes in fair value (in thousands):
			Nine Months Ended
			September 30,
			2013			2014
	Convertible debt derivative
	Balance, beginning of period		$	—		$	(388	)
	Initial valuation on date of issuance			(241	)		—
	Revaluation			(77	)		30
	Conversion of debt			—			358
	Balance, end of period		$	(318	)	$	—

Property_and_Equipment_Tables

Property and Equipment (Tables)	9 Months Ended
	Sep. 30, 2014
Property, Plant and Equipment [Abstract]	'
Schedule of Property and Equipment	'
	Property and equipment consisted of the following (in thousands):
		December 31,			September 30,
		2013			2014
	Equipment	$	5,034		$	5,940
	Software		8,948			16,293
	Furniture and fixtures		306			333
	Leasehold improvements		2,038			2,617
	Total property and equipment	$	16,326		$	25,183
	Accumulated depreciation and amortization		(5,513	)		(10,166	)
	Total property and equipment, net	$	10,813		$	15,017
Breakout of Depreciation and Amortization Expense	'
	The following table represents a detailed breakout of depreciation and amortization expense as recorded in the condensed consolidated statements of operations (in thousands):
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2013			2014			2013		2014
	Cost of revenue	$	500		$	782		$	1,094	$	2,030
	Sales and marketing		101			123			211		270
	Research and development		532			898			1,299		2,282
	General and administrative		25			49			175		259
	Total	$	1,158		$	1,852		$	2,779	$	4,841

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2014
Equity [Abstract]	'
Summary of Outstanding Restricted Stock	'
	The following table summarizes the activity of the Company’s outstanding restricted stock for the nine months ended September 30, 2014 (in thousands, expect per share amounts):
		Restricted			Weighted-
		Shares			Average
					Grant Date
					Fair Value
	Balance as of December 31, 2013		113		$	2.09
	Vested		(113	)		2.09
	Balance as of September 30, 2014		—
Summary of Accumulated Other Comprehensive Loss	'
	The following table summarizes the activity for each component of accumulated other comprehensive loss (in thousands):
		Foreign			Foreign			Accumulated
		currency			currency			other
		translation			derivative			comprehensive
					instruments			loss
	Balance as of December 31, 2013	$	(6	)	$	(114	)	$	(120	)
	Other comprehensive income (loss) before reclassifications		(38	)		10			(28	)
	Reclassifications to net income		—			62			62
	Other comprehensive income (loss)		(38	)		72			34
	Balance as of September 30, 2014	$	(44	)	$	(42	)	$	(86	)

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Summary of Stock Option Activity	'
	A summary of stock option activity for the nine months ended September 30, 2014 is summarized in the following table (in thousands, except time period and per share amounts):
			Options			Weighted-		Weighted-		Aggregate
			Outstanding			Average		Average		Intrinsic
						Exercise		Remaining		Value(1)
						Price		Contractual
								Term
								(Years)
	Balance at December 31, 2013			7,790		$	3.83		7.6	$	98,814
	Granted			50			18
	Exercised			(836	)		2.12
	Forfeited			(251	)		3.72
	Balance at September 30, 2014			6,753		$	4.16		7.5	$	99,299
	Vested and expected to vest after September 30, 2014			6,572		$	4.06		7.4	$	97,264
	Exercisable at September 30, 2014			4,627		$	3.46		7.1	$	71,264
	(1)	Aggregate intrinsic value represents the difference between the fair value of the underlying common stock and the exercise price of outstanding, in-the-money stock options.
Summary of Additional Information on Stock Option Granted, Vested and Exercised	'
	The following table summarizes additional information on stock option grants, vesting and exercises (in thousands):
			Three Months Ended					Nine Months Ended
			September 30,					September 30,
			2013			2014		2013		2014
	Total fair value of stock options granted		$	16,087		$	—	$	17,879	$	434
	Total fair value of shares vested			466			1,869		1,160		4,689
	Total intrinsic value of stock options exercised			2,765			2,897		5,567		13,012
	Cash received from stock options exercised			948			327		2,548		1,777
Summary of Restricted Stock Unit Activity	'
	A summary of restricted stock unit (“RSU”) activity for the nine months ended September 30, 2014 is summarized in the following table (in thousands, except per share amounts):
			Shares			Weighted-
						Average
						Grant Date
						Fair Value
	Balance as of December 31, 2013			1,093		$	15.48
	Granted			1,270			17.3
	Released			(13	)		16.65
	Forfeited			(198	)		16.32
	Balance as of September 30, 2014			2,152		$	16.49
Stock-Based Compensation Expense	'
	Stock-based compensation expense is included in the condensed consolidated statements of operations within the following line items (in thousands):
			Three Months Ended					Nine Months Ended
			September 30,					September 30,
			2013			2014		2013		2014
	Cost of revenue		$	67		$	305	$	133		918
	Sales and marketing			492			2,019		748		6,994
	Research and development			328			1,195		677		4,088
	General and administrative			291			968		362		3,425
	Total		$	1,178		$	4,487	$	1,920	$	15,425

Net_Income_Loss_Per_Share_Tabl

Net Income (Loss) Per Share (Tables)	9 Months Ended
	Sep. 30, 2014
Earnings Per Share [Abstract]	'
Summary of Calculation of Company's Basic and Diluted Net Loss Per Share	'
	The following table summarizes the calculation of the Company’s basic and diluted net loss per share under the two-class method attributable to common stockholders for the three months and nine months ended September 30, 2013 and 2014 (in thousands, except per share amounts):
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2013			2014			2013			2014
	Numerator:
	Net loss	$	(3,175	)	$	(8,196	)	$	(7,884	)	$	(29,981	)
	Non-cumulative dividends to preferred stockholders		—			—			—			—
	Net loss attributable to common stockholders	$	(3,175	)	$	(8,196	)	$	(7,884	)	$	(29,981	)
	Denominator:
	Weighted-average common stock outstanding, basic		21,303			49,091			20,959			39,253
	Effect of potentially dilutive stock options and restricted stock		—			—			—			—
	Weighted-average common stock outstanding, diluted		21,303			49,091			20,959			39,253
	Net loss per share, basic and diluted	$	(0.15	)	$	(0.17	)	$	(0.38	)	$	(0.76	)
Potential Shares were Excluded from Calculation of Diluted Net Loss Per Share	'
	The following potential shares were excluded from the calculation of diluted net loss per share attributable to common stockholders because their effect would have been anti-dilutive for the periods presented (in thousands):
		September 30,
		2013			2014
	Convertible preferred stock		19,247			—
	Stock options		7,634			6,753
	Restricted stock units		—			2,152
	Common stock subject to repurchase		465			201
			27,346			9,106

Initial_Public_Offering_Additi

Initial Public Offering - Additional Information (Detail) (USD $)	1 Months Ended	9 Months Ended		12 Months Ended
	Apr. 30, 2014	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Subsidiary, Sale of Stock [Line Items]	'	'	'	'
Common stock, shares issued	'	49,381,000	'	22,113,000
Proceeds from issuance of common stock	'	$1,777,000	$2,548,000	'
Payment for stock issuance cost	'	1,687,000	'	'
Subordinated convertible promissory note automatically converted into shares of common stock	157,664	'	'	'
Offering expenses	'	'	'	800,000
Reclassification to additional paid-in capital in connection with the IPO	'	220,636,000	'	9,407,000
IPO [Member]	'	'	'	'
Subsidiary, Sale of Stock [Line Items]	'	'	'	'
Common stock, shares issued	7,015,000	'	'	'
Common stock shares issued to underwriters	915,000	'	'	'
Share price per share under underwriter	19	'	'	'
Proceeds from issuance of common stock	121,800,000	'	'	'
Payment for stock issuance cost	2,100,000	'	'	'
Reclassification to additional paid-in capital in connection with the IPO	'	'	'	$2,100,000
Convertible Promissory Note [Member]	'	'	'	'
Subsidiary, Sale of Stock [Line Items]	'	'	'	'
Outstanding convertible preferred stock	19,246,714	'	'	'

Summary_of_Significant_Account3

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
			Segment
Schedule Of Significant Accounting Policies [Line Items]	'	'	'	'
Change in general and administrative expense	$4,241,000	$1,886,000	$13,010,000	$4,948,000
Change in sales and marketing expense	14,580,000	8,391,000	43,958,000	22,615,000
Change in research and development expense	11,177,000	7,821,000	34,131,000	19,666,000
Increased revenue in the current period for adjustments related to prior periods	'	'	300,000	'
Increased gains on foreign currency in the current period for adjustments related to prior periods	'	'	200,000	'
Number of operating segment	'	'	1	'
Scenario, Adjustment [Member]	'	'	'	'
Schedule Of Significant Accounting Policies [Line Items]	'	'	'	'
Change in general and administrative expense	'	1,400,000	'	3,500,000
Change in cost of revenue	'	200,000	'	400,000
Change in sales and marketing expense	'	600,000	'	1,600,000
Change in research and development expense	'	$600,000	'	$1,500,000
Accounts Receivable [Member]	'	'	'	'
Schedule Of Significant Accounting Policies [Line Items]	'	'	'	'
Threshold percentage of revenue and accounts receivable represented by major customers	'	'	10.00%	'
Revenue [Member]	'	'	'	'
Schedule Of Significant Accounting Policies [Line Items]	'	'	'	'
Threshold percentage of revenue and accounts receivable represented by major customers	'	'	10.00%	'

Summary_of_Significant_Account4

Summary of Significant Accounting Policies - Summary of Revenue or Accounts Receivable Percentage of Major Customers (Detail)

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

12 Months Ended

9 Months Ended

12 Months Ended

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Dec. 31, 2013

Dec. 31, 2013

Revenue [Member]

Revenue [Member]

Revenue [Member]

Revenue [Member]

Revenue [Member]

Revenue [Member]

Revenue [Member]

Revenue [Member]

Revenue [Member]

Revenue [Member]

Revenue [Member]

Revenue [Member]

Accounts Receivable [Member]

Accounts Receivable [Member]

Accounts Receivable [Member]

Accounts Receivable [Member]

Accounts Receivable [Member]

Accounts Receivable [Member]

Customer A [Member]

Customer A [Member]

Customer A [Member]

Customer A [Member]

Customer B [Member]

Customer B [Member]

Customer B [Member]

Customer B [Member]

Customer C [Member]

Customer C [Member]

Customer C [Member]

Customer C [Member]

Customer C [Member]

Customer D [Member]

Customer E [Member]

Customer F [Member]

Revenue or Accounts Receivable by Major Customers [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Concentration percentage

10.00%

15.00%

16.00%

12.00%

12.00%

10.00%

14.00%

10.00%

14.00%

10.00%

13.00%

14.00%

10.00%

23.00%

22.00%

11.00%

12.00%

10.00%

Summary_of_Significant_Account5

Summary of Significant Accounting Policies - Summary of Revenue or Accounts Receivable Percentage of Major Customers (Parenthetical) (Detail) (Maximum [Member])	9 Months Ended
	Sep. 30, 2014
Maximum [Member]	'
Revenue or Accounts Receivable by Major Customers [Line Items]	'
Concentration percentage	10.00%

Fair_Value_Measurements_Summar

Fair Value Measurements - Summary of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) (Fair Value, Measurements, Recurring [Member], USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Cash equivalents	'	'
Money market funds	$117,051	$15,511
Total	117,051	15,511
Liabilities:	'	'
Convertible debt derivative	'	-388
Total	-4	-429
Foreign Currency Derivative Contracts [Member]	'	'
Liabilities:	'	'
Foreign currency derivative contracts	-4	-41
Fair Value, Inputs, Level 1 [Member]	'	'
Cash equivalents	'	'
Money market funds	117,051	15,511
Total	117,051	15,511
Liabilities:	'	'
Convertible debt derivative	'	'
Total	'	'
Fair Value, Inputs, Level 1 [Member] | Foreign Currency Derivative Contracts [Member]	'	'
Liabilities:	'	'
Foreign currency derivative contracts	'	'
Fair Value, Inputs, Level 2 [Member]	'	'
Cash equivalents	'	'
Money market funds	'	'
Total	'	'
Liabilities:	'	'
Convertible debt derivative	'	'
Total	-4	-41
Fair Value, Inputs, Level 2 [Member] | Foreign Currency Derivative Contracts [Member]	'	'
Liabilities:	'	'
Foreign currency derivative contracts	-4	-41
Fair Value, Inputs, Level 3 [Member]	'	'
Cash equivalents	'	'
Money market funds	'	'
Total	'	'
Liabilities:	'	'
Convertible debt derivative	'	-388
Total	'	-388
Fair Value, Inputs, Level 3 [Member] | Foreign Currency Derivative Contracts [Member]	'	'
Liabilities:	'	'
Foreign currency derivative contracts	'	'

Fair_Value_Measurements_Reconc

Fair Value Measurements - Reconciliation of Convertible Debt Derivative Instrument Measured at Fair Value (Detail) (Fair Value, Inputs, Level 3 [Member], Convertible Debt Derivative Instrument [Member], USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Fair Value, Inputs, Level 3 [Member] | Convertible Debt Derivative Instrument [Member]	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Balance, beginning of period	($388)	'
Initial valuation on date of issuance	'	-241
Revaluation	30	-77
Conversion of debt	358	'
Balance, end of period	'	($318)

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Detail) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value Disclosures [Abstract]	'
Notes payable, carrying value	$2,418

Property_and_Equipment_Schedul

Property and Equipment - Schedule of Property and Equipment (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]	'	'
Property and equipment	$25,183	$16,326
Accumulated depreciation and amortization	-10,166	-5,513
Total property and equipment, net	15,017	10,813
Equipment [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property and equipment	5,940	5,034
Software [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property and equipment	16,293	8,948
Furniture and Fixtures [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property and equipment	333	306
Leasehold Improvements [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property and equipment	$2,617	$2,038

Property_and_Equipment_Additio

Property and Equipment - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Property, Plant and Equipment [Line Items]	'	'	'	'	'
Capital lease obligations	$900,000	'	$900,000	'	$1,300,000
Property and equipment	25,183,000	'	25,183,000	'	16,326,000
Accumulated depreciation	10,166,000	'	10,166,000	'	5,513,000
Capitalized internal-use software development costs	3,200,000	1,400,000	7,100,000	4,900,000	'
Capitalized internal-use software cost, net	10,400,000	'	10,400,000	'	6,400,000
Amortization expense related to capitalized internal-use software	1,200,000	700,000	3,000,000	1,700,000	'
Capital Lease Obligations [Member] | Computer Equipment [Member]	'	'	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'	'	'
Property and equipment	1,400,000	'	1,400,000	'	1,400,000
Accumulated depreciation	$500,000	'	$500,000	'	$200,000

Property_and_Equipment_Breakou

Property and Equipment - Breakout of Depreciation and Amortization Expense (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Property, Plant and Equipment [Line Items]	'	'	'	'
Depreciation and amortization	$1,852	$1,158	$4,841	$2,779
Cost of Revenue [Member]	'	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'	'
Depreciation and amortization	782	500	2,030	1,094
Sales and Marketing [Member]	'	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'	'
Depreciation and amortization	123	101	270	211
Research and Development [Member]	'	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'	'
Depreciation and amortization	898	532	2,282	1,299
General and Administrative [Member]	'	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'	'
Depreciation and amortization	$49	$25	$259	$175

Commitments_and_Contingencies_

Commitments and Contingencies - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Contingencies And Commitments [Line Items]	'	'	'	'	'	'
Operating lease agreement expire period	'	'	'	'2016	'	'
Capital lease term	'36 months	'	'	'	'	'
Weighted-average interest rate implicit in leases	6.00%	'	'	'	'	'
Rent expense under operating leases	'	$1.10	$0.90	$3.30	$2	'
Total outstanding letters of credit	'	1.1	'	1.1	'	1.1
Arlington [Member]	'	'	'	'	'	'
Contingencies And Commitments [Line Items]	'	'	'	'	'	'
Total outstanding letters of credit	'	1	'	1	'	'
San Francisco [Member]	'	'	'	'	'	'
Contingencies And Commitments [Line Items]	'	'	'	'	'	'
Total outstanding letters of credit	'	$0.10	'	$0.10	'	'

Stockholders_Equity_Additional

Stockholders' Equity - Additional Information (Detail) (Restricted Stock [Member], USD $)	1 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2013
Restricted Stock [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Restricted stock, shares sold	0.4	'
Restricted stock, per share	$2.09	$2.09
Total issuance price of restricted stock	$0.90	'
Restricted stock, vesting period	'3 years	'
Restricted stock vesting percentage after first year	36.00%	'
Repurchase option liability related to restricted stock	'	$0.20

Stockholders_Equity_Summary_of

Stockholders' Equity - Summary of Outstanding Restricted Stock (Detail) (Restricted Stock [Member], USD $)	9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2011
Restricted Stock [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Restricted Shares, Beginning balance	113	'
Restricted Shares, Vested	-113	'
Restricted Shares, Ending Balance	'	'
Weighted-Average Grant Date Fair Value, Beginning Balance	$2.09	$2.09
Weighted-Average Grant Date Fair Value, Vested	$2.09	'
Weighted-Average Grant Date Fair Value, Ending Balance	'	$2.09

Stockholders_Equity_Summary_of1

Stockholders' Equity - Summary of Accumulated Other Comprehensive Loss (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Equity [Abstract]	'	'	'	'
Foreign currency translation, Beginning balance	'	'	($6)	'
Foreign currency translation, Other comprehensive income (loss) before reclassifications	'	'	-38	'
Foreign currency translation, Reclassifications to net income	'	'	'	'
Foreign currency translation, Other comprehensive income (loss)	-89	58	-38	-16
Foreign currency translation, Ending balance	-44	'	-44	'
Foreign currency derivative instruments, Beginning balance	'	'	-114	'
Foreign currency derivative instruments, Other comprehensive income (loss) before reclassifications	'	'	10	'
Foreign currency derivative instruments, Reclassifications to net income	'	'	62	'
Foreign currency derivative instruments, Other comprehensive income (loss)	31	-75	72	-18
Foreign currency derivative instruments, Ending balance	-42	'	-42	'
Accumulated other comprehensive loss, Beginning balance	'	'	-120	'
Accumulated other comprehensive loss, Other comprehensive income (loss) before reclassifications	'	'	-28	'
Accumulated other comprehensive loss, Reclassifications to net income	'	'	62	'
Total other comprehensive income (loss)	-58	-17	34	-34
Accumulated other comprehensive loss, Ending balance	($86)	'	($86)	'

StockBased_Compensation_Summar

Stock-Based Compensation - Summary of Stock Option Activity (Detail) (USD $)	9 Months Ended	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'	'
Options Outstanding, Beginning Balance	7,790	'
Options Outstanding, Granted	50	'
Options Outstanding, Exercised	-836	'
Options Outstanding, Forfeited	-251	'
Options Outstanding, Ending Balance	6,753	7,790
Options Outstanding, Vested and expected to vest Ending Balance	6,572	'
Options Outstanding, Exercisable Ending Balance	4,627	'
Weighted-Average Exercise Price, Beginning Balance	$3.83	'
Weighted-Average Exercise Price, Granted	$18	'
Weighted-Average Exercise Price, Exercised	$2.12	'
Weighted-Average Exercise Price, Forfeited	$3.72	'
Weighted-Average Exercise Price, Ending Balance	$4.16	$3.83
Weighted-Average Exercise Price, Vested and expected to vest Ending Balance	$4.06	'
Weighted-Average Exercise Price, Exercisable Ending Balance	$3.46	'
Weighted-Average Remaining Contractual Term	'7 years 6 months	'7 years 7 months 6 days
Weighted-Average Remaining Contractual Term, Vested or expected to vest Ending Balance	'7 years 4 months 24 days	'
Weighted-Average Remaining Contractual Term, Exercisable	'7 years 1 month 6 days	'
Aggregate Intrinsic Value, Beginning Balance	$98,814	'
Aggregate Intrinsic Value, Ending Balance	99,299	98,814
Aggregate Intrinsic Value, Vested or expected to vest Ending Balance	97,264	'
Aggregate Intrinsic Value, Exercisable Ending Balance	$71,264	'

StockBased_Compensation_Additi

Stock-Based Compensation - Additional Information (Detail) (USD $)	3 Months Ended	9 Months Ended				12 Months Ended
In Millions, except Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Dec. 31, 2013
			Restricted Stock Units [Member]	Restricted Stock Units [Member]	2007 Stock Plan [Member]	2007 Stock Plan [Member]
				Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'	'
Stock options subject to repurchase	'	'	'	'	200,000	300,000
Aggregate exercise price	'	'	'	'	$0.50	$0.90
Share-based awards granted	'	'	1,270,000	1,100,000	'	'
Share-based awards, aggregate grant-date fair value	'	'	'	18.6	'	'
Unrecognized stock-based compensation expense	15.1	15.1	'	'	'	'
Unrecognized stock-based compensation expense related to RSUs	'	'	20.9	'	'	'
Unvested stock options granted, expected to be recognized	'	'2 years 10 months 24 days	'2 years 8 months 12 days	'	'	'
Capitalized stock-based compensation expense	$0.40	$0.80	'	'	'	'

StockBased_Compensation_Summar1

Stock-Based Compensation - Summary of Additional Information on Stock Option Granted, Vested and Exercised (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'	'	'	'
Total fair value of stock options granted	'	$16,087	$434	$17,879
Total fair value of shares vested	1,869	466	4,689	1,160
Total intrinsic value of stock options exercised	2,897	2,765	13,012	5,567
Cash received from stock options exercised	$327	$948	$1,777	$2,548

StockBased_Compensation_Summar2

Stock-Based Compensation - Summary of Restricted Stock Unit Activity (Detail) (Restricted Stock Units [Member], USD $)	9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2014
Restricted Stock Units [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Shares, Beginning balance	1,093
Shares, Granted	1,270
Shares, Released	-13
Shares, Forfeited	-198
Shares, Ending balance	2,152
Weighted-Average Grant Date Fair Value, Unvested at Beginning balance	$15.48
Weighted-Average Grant Date Fair Value, Granted	$17.30
Weighted-Average Grant Date Fair Value, Released	$16.65
Weighted-Average Grant Date Fair Value, Forfeited	$16.32
Weighted-Average Grant Date Fair Value, Unvested at Ending balance	$16.49

StockBased_Compensation_StockB

Stock-Based Compensation - Stock-Based Compensation Expense (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]	'	'	'	'
Stock-based compensation expense	$4,487	$1,178	$15,425	$1,920
Cost of Revenue [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]	'	'	'	'
Stock-based compensation expense	305	67	918	133
Sales and Marketing [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]	'	'	'	'
Stock-based compensation expense	2,019	492	6,994	748
Research and Development [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]	'	'	'	'
Stock-based compensation expense	1,195	328	4,088	677
General and Administrative [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]	'	'	'	'
Stock-based compensation expense	$968	$291	$3,425	$362

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	Sep. 30, 2014
Income Tax Disclosure [Abstract]	'
Unrecognized tax benefits	$0

Net_Income_Loss_Per_Share_Summ

Net Income (Loss) Per Share - Summary of Calculation of Company's Basic and Diluted Net Loss Per Share (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Numerator:	'	'	'	'
Net loss	($8,196)	($3,175)	($29,981)	($7,884)
Non-cumulative dividends to preferred stockholders	'	'	'	'
Net loss attributable to common stockholders	($8,196)	($3,175)	($29,981)	($7,884)
Denominator:	'	'	'	'
Weighted-average common stock outstanding, basic	49,091	21,303	39,253	20,959
Effect of potentially dilutive stock options and restricted stock	'	'	'	'
Weighted-average common stock outstanding, diluted	49,091	21,303	39,253	20,959
Net loss per share, basic and diluted	($0.17)	($0.15)	($0.76)	($0.38)

Net_Income_Loss_Per_Share_Pote

Net Income (Loss) Per Share - Potential Shares were Excluded from Calculation of Diluted Net Loss Per Share (Detail)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Antidilutive securities excluded from computation of earnings per share	9,106	27,346
Convertible Preferred Stock [Member]	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Antidilutive securities excluded from computation of earnings per share	'	19,247
Stock Options [Member]	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Antidilutive securities excluded from computation of earnings per share	6,753	7,634
Restricted Stock Units [Member]	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Antidilutive securities excluded from computation of earnings per share	2,152	'
Common Stock Subject to Repurchase [Member]	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Antidilutive securities excluded from computation of earnings per share	201	465

Geographic_Information_Additio

Geographic Information - Additional Information (Detail) (Revenue [Member])	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Concentration Risk [Line Items]	'	'	'	'
Revenue concentration percentage	'	'	10.00%	'
United States [Member]	'	'	'	'
Concentration Risk [Line Items]	'	'	'	'
Revenue concentration percentage	0.84%	91.00%	0.85%	0.92%