Proofpoint (PFPT) 10-Q 6 Aug 15 2015 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information Document - shares	6 Months Ended
	Jun. 30, 2015	Jul. 24, 2015
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q2
Entity Registrant Name	PROOFPOINT INC.
Entity Central Index Key (CIK)	1,212,458
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		40,018,939

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	$ 402,144	$ 180,337
Short-term investments	8,510	34,649
Accounts receivable, net of allowance for doubtful accounts of $177 and $429 as of June 30, 2015 and December 31, 2014, respectively	44,298	40,912
Inventory	435	499
Deferred product costs, current	1,881	1,847
Prepaid expenses and other current assets	8,175	7,994
Total current assets	465,443	266,238
Property and equipment, net	26,774	18,718
Deferred product costs, noncurrent	614	307
Goodwill	126,525	107,504
Intangible assets, net	33,962	27,086
Other noncurrent assets	3,872	4,163
Total assets	657,190	424,016
Current liabilities
Accounts payable	12,977	9,249
Accrued liabilities	24,573	24,220
Notes payable and lease obligations, current	2	695
Deferred rent, current	486	569
Deferred revenue, current	142,087	123,550
Total current liabilities	180,125	158,283
Convertible senior notes	335,728	161,396
Deferred rent, noncurrent	1,986	2,099
Other long term liabilities	5,177	6,640
Deferred revenue, noncurrent	41,854	39,125
Total liabilities	564,870	367,543
Stockholders’ equity
Convertible preferred stock, $0.0001 par value, 5,000 shares authorized	0	0
Common stock, $0.0001 par value; 200,000 shares authorized; 39,897 and 38,665 shares issued and outstanding at June 30, 2015 and December 31, 2014, respectively	4	4
Additional paid-in capital	413,212	330,744
Accumulated Other Comprehensive Income (Loss), Net of Tax	(2)	(27)
Accumulated deficit	(320,894)	(274,248)
Total stockholders’ equity	92,320	56,473
Total liabilities and stockholders’ equity	$ 657,190	$ 424,016

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets Parenthetical - USD ($) shares in Thousands, $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Allowance for doubtful accounts receivable, current	$ 177	$ 429
Preferred Stock, Shares Authorized	5,000	5,000
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0
Preferred Stock, Par or Stated Value Per Share	$ 0.0001	$ 0.0001
Number of shares of common stock reserved for future issuance
Par value of common stock (USD per share)	$ 0.0001	$ 0.0001
Common Stock, Shares Authorized	200,000	200,000
Common stock issued (in shares)	39,897	38,665
Common stock outstanding (in shares)	39,897	38,665

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Revenue:
Subscription		$ 61,778	$ 45,047	$ 117,634	$ 86,251
Hardware and services		1,768	1,351	3,675	2,851
Revenue, net		63,546	46,398	121,309	89,102
Cost of revenue:
Subscription		16,829	12,544	33,163	23,995
Hardware and services		2,995	2,717	5,949	4,977
Total cost of revenue	[1],[2]	19,824	15,261	39,112	28,972
Gross profit		43,722	31,137	82,197	60,130
Operating expense:
Research and development		18,659	12,298	34,367	24,246
Sales and marketing		38,017	24,180	70,929	46,998
General and administrative		8,495	6,846	15,828	12,352
Total operating expense	[1],[2]	65,171	43,324	121,124	83,596
Operating loss		(21,449)	(12,187)	(38,927)	(23,466)
Interest expense		(3,332)	(2,798)	(6,185)	(5,571)
Other income (expense), net		(80)	7	(1,260)	(192)
Loss before (provision for) benefit from income taxes		(24,861)	(14,978)	(46,372)	(29,229)
(Provision for) benefit from income taxes		(112)	(147)	(274)	(291)
Net loss		$ (24,973)	$ (15,125)	$ (46,646)	$ (29,520)
Net loss per share, basic and diluted		$ (0.63)	$ (0.41)	$ (1.19)	$ (0.80)
Weighted average shares outstanding, basic and diluted (in shares)		39,567	37,115	39,264	36,842
Stock-based Compensation Expense				$ 729
Intangible amortization expense		$ 2,917	$ 2,109	5,624	$ 4,069
Cost of subscription revenue [Member]
Operating expense:
Stock-based Compensation Expense		1,148	511	2,263	923
Intangible amortization expense		1,589	974	2,969	1,803
Cost of hardware and services revenue [Member]
Operating expense:
Stock-based Compensation Expense		250	144	504	273
Research and development [Member]
Operating expense:
Stock-based Compensation Expense		5,762	2,450	9,700	4,484
Intangible amortization expense		23	24	46	47
Sales and marketing [Member]
Operating expense:
Stock-based Compensation Expense		5,157	2,408	10,026	4,505
Intangible amortization expense		1,304	1,100	2,597	2,197
General and administrative [Member]
Operating expense:
Stock-based Compensation Expense		2,918	1,815	5,168	3,116
Intangible amortization expense		$ 1	$ 11	$ 12	$ 22
[1]	Includes intangible amortization expense as follows:Three Months Ended September 30, Nine Months Ended September 30, 2014 2013 2014 2013Cost of subscription revenue1,589 974 2,969 1,803Research and development23 24 46 47Sales and marketing1,304 1,100 2,597 2,197General and administrative1 11 12 22
[2]	Includes stock‑based compensation expense as follows: Three Months Ended September 30, Nine Months Ended September 30, 2014 2013 2014 2013Cost of subscription revenue1,148 511 2,263 923Cost of hardware and services revenue250 144 504 273Research and development5,762 2,450 9,700 4,484Sales and marketing5,157 2,408 10,026 4,505General and administrative2,918 1,815 5,168 3,116

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Net loss	$ (24,973)	$ (15,125)	$ (46,646)	$ (29,520)
Other comprehensive loss, net of tax
Unrealized gains (losses) on investments, net	5	0	25	0
Comprehensive loss	$ (24,968)	$ (15,125)	$ (46,621)	$ (29,520)

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Adjustments to reconcile net loss to net cash (used in) provided by operating activities
Net loss	$ (46,646)	$ (29,520)
Depreciation and amortization	11,427	8,105
Loss on disposal of property and equipment	115	0
Accretion of investments	206	15
Provision for allowance for doubtful accounts	(252)	(5)
Stock‑based compensation	27,661	13,301
Deferred income taxes and tax credits	144	(70)
Change in fair value of contingent earn-out liability	0	5
Amortization of debt issuance costs and accretion of debt discount	4,962	4,316
Changes in assets and liabilities, net of effect of acquisitions:
Accounts receivable	(2,014)	(47)
Inventory	64	(483)
Deferred product costs	(341)	(995)
Increase (Decrease) in Prepaid Expense	(782)	(1,461)
Other current assets	585	(765)
Noncurrent assets	109	(78)
Accounts payable	825	(462)
Accrued liabilities	(2,855)	(3,376)
Increase (Decrease) in Contingent Earn Out Payment	0	5
Deferred rent	(221)	1,123
Deferred revenue	20,566	7,580
Net cash provided by operating activities	13,553	(2,822)
Cash flows from investing activities
Proceeds from sale and maturity of short-term investments	25,959	8,000
Purchase of property and equipment	(10,427)	(6,023)
Payments to acquire businesses, net of cash acquired	(31,624)	(22,754)
Net cash used in investing activities	(16,092)	(20,777)
Cash flows from financing activities
Proceeds from issuance of common stock, net of repurchases	9,676	8,671
Tax Withholdings Related To Net Share Settlements of Restricted Stock Awards and Units	(8,427)	(752)
Payments of debt issuance costs	0	(191)
Repayments of equipment financing loans	(693)	(825)
Net cash provided by financing activities	224,346	6,658
Net (decrease) increase in cash and cash equivalents	221,807	(16,941)
Proceeds from convertible debt	223,790	0
Cash and cash equivalents
Beginning of period	180,337	243,786
End of period	402,144	226,845
Supplemental disclosure of noncash investing and financing information
Unpaid purchase of property and equipment	5,949	3,154
Earn Out Payment, Financing Activities	$ 0	$ (245)

The Company and Summary of Sign

The Company and Summary of Significant Accounting Policies (Notes)	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
The Company and Summary of Significant Accounting Policies	The Company and Summary of Significant Accounting Policies The Company Proofpoint, Inc. (the “Company”) was incorporated in Delaware in June 2002 and is headquartered in California. Proofpoint is a leading security-as-a-service provider that enables large and mid-sized organizations worldwide to defend, protect, archive and govern their most sensitive data. The Company's security-as-a-service platform is comprised of a number of data protection solutions, including threat protection and incident response, regulatory compliance, archiving, governance and eDiscovery, and secure communication. Basis of Presentation and Consolidation The condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All significant inter-company transactions and balances have been eliminated in consolidation. The Company acquired one company in the six months ended June 30, 2015 and two companies in the year ended December 31, 2014. These acquisitions are more fully described in note 2, "Acquisitions". The consolidated financial statements include the results of operations from these business combinations from their date of acquisition. The accompanying condensed consolidated financial statements have been prepared in accordance with United States generally accepted accounting principles (“GAAP”), pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Certain information and note disclosures have been condensed or omitted pursuant to such rules and regulations. The accompanying Condensed Consolidated Balance Sheet as of December 31, 2014 is derived from audited financial statements as of that date but does not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements. The unaudited condensed consolidated financial statements have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the periods presented. The results of operations for the three and six months ended June 30, 2015 are not necessarily indicative of the results to be expected for the year ending December 31, 2015 or for other interim periods or for future years. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and accompanying notes for the year ended December 31, 2014 included in the Company’s Annual Report on Form 10-K filed with the SEC. The Company’s significant accounting policies are described in note 1 to those audited consolidated financial statements. Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America 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 expenses during the reporting period. Actual results could differ from those estimates and such difference may be material to the financial statements. Goodwill and Intangible Assets Goodwill represents the excess of the purchase price of the acquired enterprise over the fair value of identifiable assets acquired and liabilities assumed. The Company performs an annual goodwill impairment test during the fourth quarter of a calendar year and more frequently if an event or circumstances indicates that impairment may have occurred. For the purposes of impairment testing, the Company has determined that it has one operating segment and one reporting unit. The Company performs a two-step impairment test of goodwill whereby the fair value of the reporting unit is compared to its carrying value. If the fair value of the reporting unit exceeds the carrying value of the net assets assigned to that unit, goodwill is not considered impaired and further testing is not required. If the carrying value of the net assets assigned to the reporting unit exceeds the fair value of the reporting unit, then the Company must perform the second step of the impairment test in order to determine the implied fair value of the reporting unit’s goodwill. If the carrying value of a reporting unit’s goodwill exceeds its implied fair value, then impairment loss equal to the difference is recorded. The identification and measurement of goodwill impairment involves the estimation of the fair value of the Company. The estimate of fair value of the Company, based on the best information available as of the date of the assessment, is subjective and requires judgment, including management assumptions about expected future revenue forecasts and discount rates, changes in the overall economy, trends in the stock price and other factors. No impairment indicators were identified by the Company as of June 30, 2015 . Intangible assets consist of developed technology, customer relationships, non-compete arrangements, trademarks and patents, order backlog and in-process research and development asset. The values assigned to intangibles are based on estimates and judgments regarding expectations for success and life cycle of solutions and technologies acquired. Intangible assets are amortized on a straight-line basis over their estimated lives, which approximate the pattern in which the economic benefits of the intangible assets are consumed, as follows (in years): Low High Patents 4 5 Developed technology 3 7 Customer relationships 2 7 Non-compete agreements 2 4 Order backlog 1 2 Trade names and trademarks 1 5 In-process research and development asset is not amortized until the associated project is completed. Revenue Recognition The Company derives its revenue primarily from two sources: (1) subscription revenue for rights related to the use of the security-as-a-service platform and (2) hardware, training and professional services revenue provided to customers related to their use of the platform. The Company records its revenues net of any value added or sales tax. Subscription revenue is derived from a subscription‑based enterprise licensing model with contract terms typically ranging from one to three years, and consists of (i) subscription fees from the licensing of the security-as-a-service platform, (ii) subscription fees for access to the on-demand elements of the platform and (iii) subscription fees for the right to access the Company’s customer support services. Revenue is recognized when all of the following criteria have been met: • Persuasive evidence of an arrangement exists; • Delivery has occurred or services have been rendered; • Sales price is fixed or determinable; and • Collectability is reasonably assured The Company's revenue arrangements typically include subscription services to its security-as-a-service platform. These hosted on demand service arrangements do not provide customers with the right to take possession of the software supporting the hosted services. Certain arrangements also include the sale of hardware appliances. Revenue from hardware appliances containing software components and hardware components that function together to deliver the hardware appliance's essential functionality is excluded from the scope of the industry specific revenue recognition guidance. The Company recognizes revenue from its hosted on demand services in accordance with general revenue recognition accounting guidance. Only revenue derived from the licensing of the software is recognized in accordance with the industry specific revenue guidance. The Company applies industry-specific software revenue recognition guidance to transactions involving the licensing of software, as well as related support, training, and other professional services. The Company has analyzed all of the elements included in its multiple element software arrangements and has determined that it does not have sufficient VSOE of fair value to allocate revenue to its subscription and software license agreements, support, training, and professional services. The Company defers all revenue under the software arrangement until the commencement of the subscription services and any associated professional services. Once the subscription services and the associated professional services have commenced, the entire fee from the arrangement is recognized ratably over the remaining period of the arrangement. If the professional services are essential to the functionality of the subscription, then the revenue recognition does not commence until such services are completed. When a sales arrangement contains multiple elements, such as hardware appliances, subscription services, customer support services, and/or professional services, the Company allocates revenue to each unit of accounting or element based on a selling price hierarchy. 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. When applying the relative selling price method, the Company determines the selling price for each deliverable using vendor-specific objective evidence (“VSOE”) of selling price. If VSOE does not exist, the Company uses third-party evidence (“TPE”) of selling price. If neither VSOE nor TPE of selling price exist for a deliverable, the Company uses its best estimate of selling price ("BESP") for that deliverable. Revenue allocated to each element is then recognized when the basic revenue recognition criteria are met for each element. The Company determines BESP for an individual element within a multiple element revenue arrangement using the same methods utilized to determine the selling price of an element sold on a standalone basis. The Company estimates the selling price for its subscription solutions by considering internal factors such as historical pricing practices and it estimates the selling price of hardware and other services using a cost plus model. Hardware appliance revenue is recognized upon shipment. Subscription and support revenue are recognized over the contract period commencing on the start date of the contract. Professional services and training, when sold with hardware appliances or subscription and support services, are accounted for separately when those services have standalone value. In determining whether professional services and training services can be accounted for separately from subscription and support services, the Company considers the following factors: availability of the services from other vendors, the nature of the services, and the dependence of the subscription services on the customer’s decision to buy the professional services. If professional services and training do not qualify for separate accounting, the Company recognizes the professional services and training ratably over the contract term of the subscription services. Delivery generally occurs when the hardware appliance is delivered to a common carrier freight on board shipping point by the Company or the hosted service has been activated and communicated to the customer accordingly. The Company’s fees are typically considered to be fixed or determinable at the inception of an arrangement and are negotiated at the outset of an arrangement, generally based on specific products and quantities to be delivered. In the event payment terms are provided that differ significantly from the Company's standard business practices, the fees are deemed to not be fixed or determinable and revenue is recognized as the fees become paid. The Company assesses collectability based on a number of factors, including credit worthiness of the customer and past transaction history of the customer. Through June 30, 2015 , the Company has not experienced significant credit losses. Deferred Revenue Deferred revenue primarily consists of billings or payments received in advance of revenue recognition from the sale of the Company’s subscription fees, training and professional services. Once the revenue recognition criteria are met, this revenue is recognized ratably over the term of the associated contract. Comprehensive Loss Comprehensive loss includes all changes in equity that are not the result of transactions with stockholders. The Company’s comprehensive loss consists of its net loss and changes in unrealized gains (losses) from its available-for-sale investments. The Company had no material reclassifications out of accumulated other comprehensive loss into net loss for the three and six months ended June 30, 2015 and 2014 . Recent Accounting Policies In April 2015, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update No. 2015-03, Interest - Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs (ASU 2015-03), which requires the Company to present such costs in the balance sheet as a direct deduction from the related debt liability rather than as an asset. Amortization of the costs will continue to be reported as interest expense. ASU 2015-03 is effective for fiscal years beginning after December 15, 2015 and interim periods within those fiscal years, with early adoption permitted. The Company early adopted this ASU effective during the second quarter of 2015 and has applied it retrospectively to all prior periods presented. Consequently, other long-term assets and convertible senior notes liabilities as of December 31, 2014 included in the consolidated balance sheet herein were reduced by $234 . There was no impact on the Company's results of operations or cash flows due to the adoption of this standard. In May 2014, the FASB issued Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers: Topic 606 (ASU 2014-09), to supersede nearly all existing revenue recognition guidance under U.S. GAAP. The core principle of ASU 2014-09 is to recognize revenues when promised goods or services are transferred to customers in an amount that reflects the consideration that is expected to be received for those goods or services. ASU 2014-09 defines a five step process to achieve this core principle and, in doing so, it is possible more judgment and estimates may be required within the revenue recognition process than required under existing U.S. GAAP including identifying performance obligations in the contract, estimating the amount of variable consideration to include in the transaction price and allocating the transaction price to each separate performance obligation. Originally, ASU 2014-09 was effective for the Company starting January 1, 2017 using either of two methods: (i) retrospective to each prior reporting period presented with the option to elect certain practical expedients as defined within ASU 2014-09; or (ii) retrospective with the cumulative effect of initially applying ASU 2014-09 recognized at the date of initial application and providing certain additional disclosures as defined per ASU 2014-09. In July 2015, the FASB voted to amend ASU 2014-09 by approving a one-year deferral of the effective date as well as providing the option to early adopt the standard on the original effective date. The Company is currently evaluating the timing and impact of the adoption of ASU 2014-09 on its consolidated financial statements.

Acquisitions (Notes)

Acquisitions (Notes)	6 Months Ended
	Jun. 30, 2015
Acquisitions [Abstract]
Business Combination Disclosure [Text Block]	Acquisitions Acquisitions are accounted for under the purchase method of accounting in which the tangible and identifiable intangible assets and liabilities of each acquired company are recorded at their respective fair values as of each acquisition date, including an amount for goodwill representing the difference between the respective acquisition consideration and fair values of identifiable net assets. The Company believes that for each acquisition, the combined entities will achieve savings in corporate overhead costs and opportunities for growth through expanded geographic and customer segment diversity with the ability to leverage additional products and capabilities. These factors, among others, contributed to a purchase price in excess of the estimated fair value of each acquired company's net identifiable assets acquired and, as a result, goodwill was recorded in connection with each acquisition. Goodwill related to each acquisition below, other than Emerging Threats Pro, LLC, is not deductible for tax purposes. While the Company uses its best estimates and assumptions as part of the purchase price allocation process to value assets acquired and liabilities assumed at the acquisition date, these estimates and assumptions are subject to refinement. When additional information becomes available, such as finalization of negotiations of working capital adjustments and tax related matters, the Company may revise its preliminary purchase price allocation. As a result, during the preliminary purchase price allocation period, which may be up to one year from the acquisition date, the Company may record adjustments to the assets acquired and liabilities assumed, with the corresponding offset to goodwill. Subsequent to the purchase price allocation period, adjustments to assets acquired or liabilities assumed are recognized in the operating results. During the six months period ended June 30, 2015 and for the year ended December 31, 2014, the Company acquired a total of 3 companies (collectively, the "Acquisitions") which are further described below. Emerging Threats Pro, LLC On March 6, 2015 (the "Emerging Threats Acquisition Date"), pursuant to the terms of a Purchase Agreement, the Company acquired 100% of membership interests in Emerging Threats Pro, LLC ("Emerging Threats"). Based in Indianapolis, Indiana, Emerging Threats provides threat intelligence solutions to help protect networks from known or potentially malicious threats. With this acquisition, the Company intends to integrate Emerging Threat's advanced threat intelligence solutions with its existing Targeted Attack Protection and Threat Response security solutions to advance threat detection and response across the completed attack chain. The combined technology will provide customers with deeper insight into cyberthreats, enabling them to react faster to inbound cyberattacks, and to identify, block, and disable previously undetected malware already embedded in their organizations. The Company has provisionally estimated the fair values for the acquired tangible and identifiable intangible assets and liabilities assumed at the Emerging Threats Acquisition Date. The amounts reported were considered provisional as the Company was completing the valuation work to determine the fair value of certain assets acquired and liabilities assumed. The results of operations and the provisional fair values of the acquired assets and liabilities assumed have been included in the accompanying condensed consolidated financial statements since the Emerging Threat Acquisition Date. Revenue from Emerging Threats was not material for the three and six months ended June 30, 2015, and due to the continued integration of the combined businesses, it was impractical to determine the earnings. The total purchase price was $31,803 , net of cash acquired of $52 , of which $3,662 was paid in the second quarter of 2015. Of the cash consideration paid, $6,000 was held in escrow, to secure indemnification obligations, which has not been released as of the filing date of this Quarterly Report on Form 10-Q. The Company incurred $275 in acquisition-related costs which were recorded within operating expenses for the six months ended June 30, 2015. Fair value of acquired assets and liabilities assumed The determination of the fair values of the assets acquired and liabilities assumed has been prepared on a provisional basis and changes to that determination may occur as additional information becomes available. The following table summarizes the fair values of tangible and intangible assets acquired, liabilities assumed and goodwill: Estimated Estimated Current assets acquired $ 1,284 N/A Fixed assets acquired 174 N/A Liabilities assumed (448 ) N/A Deferred revenue assumed (700 ) N/A Holdback liability to the sellers (3,662 ) N/A Trade names 200 2 Customer relationships 4,200 7 Order Backlog 200 1 Developed technology 7,900 7 Goodwill 19,045 Indefinite $ 28,193 Nexgate, Inc. On October 31, 2014 (the "Nexgate Acquisition Date"), pursuant to the terms of an Agreement and Plan of Merger, a wholly-owned subsidiary of the Company merged with and into Nexgate, Inc. ("Nexgate"), with Nexgate surviving as a wholly-owned subsidiary of the Company. Formerly based in Burlingame, California, Nexgate provides cloud-based brand protection and compliance for enterprise social media accounts. With this acquisition, the Company's customers can effectively protect their online brand presence and social media communication infrastructure. Nexgate technology identifies and remediates fraudulent social media accounts, account hacks, and content that contains malware, spam and abusive language. In addition, the Nexgate solution enforces policy on authorized accounts and posts for compliance with a wide-range of social media regulatory requirements. The Company has provisionally estimated the fair values for the acquired tangible and identifiable intangible assets and liabilities assumed at the Nexgate Acquisition Date. The amounts reported were considered provisional as the Company was completing the valuation work to determine the fair value of certain assets acquired and liabilities assumed. The results of operations and the provisional fair values of the acquired assets and liabilities assumed have been included in the accompanying consolidated financial statements since the Nexgate Acquisition Date. At the Nexgate Acquisition Date, the Company paid $31,771 in cash consideration, net of cash acquired of $1,032 . Of the cash consideration paid, $5,250 was held in escrow to secure indemnification obligations, which has not been released as of the filing date of this Quarterly Report on Form 10-Q. Fair value of acquired assets and liabilities assumed The determination of the fair values of the assets acquired and liabilities assumed has been prepared on a provisional basis and changes to that determination may occur as additional information becomes available. The following table summarizes the fair values of tangible assets acquired, liabilities assumed, intangible assets and goodwill: Estimated Estimated Current assets acquired $ 1,340 N/A Fixed assets acquired 15 N/A Liabilities assumed (64 ) N/A Deferred revenue assumed (600 ) N/A Customer relationships 3,000 7 Order backlog 200 2 Developed technology 3,200 4 In-process research and development 900 N/A Deferred tax liability, net (792 ) N/A Goodwill 25,604 Indefinite $ 32,803 NetCitadel, Inc. On May 13, 2014 (the "NetCitadel Acquisition Date"), pursuant to the terms of an Agreement and Plan of Merger, a wholly-owned subsidiary of the Company merged with and into NetCitadel, Inc. ("NetCitadel"), with NetCitadel surviving as a wholly-owned subsidiary of the Company. Formerly based in Mountain View, California, NetCitadel is a pioneer in the field of automated security incident response. The acquisition extends the reach and capabilities of the Company's existing advanced threat solutions, adding additional threat verification and containment capabilities via an open platform that unifies products from the Company and other vendors. The results of operations and the fair values of the acquired assets and liabilities assumed have been included in the accompanying consolidated financial statements since the NetCitadel Acquisition Date. At the NetCitadel Acquisition Date, the Company paid $22,731 . Of the cash consideration paid, $3,369 was held in escrow to secure indemnification obligations, which has not been released as of the filing date of this Form 10-Q. Fair value of acquired assets and liabilities assumed The following table summarizes the fair values of tangible assets acquired, liabilities assumed, intangible assets and goodwill: Fair Value Estimated Tangible assets acquired $ 14 N/A Liabilities assumed (1,267 ) N/A Customer relationships 100 5 Developed technology 5,500 5 Goodwill 18,384 Indefinite $ 22,731 Pro Forma Financial Information The following unaudited pro forma financial information presents the combined results of operations for the three and six months ended June 30, 2015 and 2014 of the Company, Emerging Threats, assuming that Emerging Threats was acquired as of January 1, 2014, and NetCitadel, assuming that NetCitadel was acquired as of January 1, 2013. Adjustments were made to give effect to pro forma events that are directly attributable to the acquisitions such as amortization expense of acquired intangible assets, stock-based compensation directly attributable to the acquisition and acquisition-related transaction costs. The unaudited pro forma results do not reflect any operating efficiencies or potential cost savings which may result from the consolidation of the operations of the Company and acquired businesses. Accordingly, these unaudited pro forma results are presented for informational purposes only and are not necessarily indicative of what the actual results of operations of the combined company would have been if the acquisitions had occurred at the beginning of the period presented, nor are they indicative of future results of operations: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Total revenue $ 63,335 $ 47,274 $ 121,104 $ 90,719 Net loss (24,923 ) (16,304 ) (48,116 ) (32,150 ) Basic and diluted net loss per share $ (0.63 ) $ (0.44 ) $ (1.23 ) $ (0.87 ) The unaudited pro forma financial information includes non-recurring acquisition-related transaction costs of $275 for the six months ended June 30, 2014 .

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Notes)	6 Months Ended
	Jun. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets The goodwill activity and balances are presented below: Balance at December 31, 2014 $ 107,504 Add: Goodwill from acquisitions 19,395 Less: Other purchase price allocation adjustments to Goodwill (374 ) Balance at June 30, 2015 $ 126,525 The goodwill balance as of June 30, 2015 was the result of the Company's acquisitions. Intangible Assets Intangible assets, excluding goodwill, consisted of the following: June 30, 2015 December 31, 2014 Gross Accumulated Net Gross Accumulated Net Developed technology $ 46,068 $ (24,508 ) $ 21,560 $ 38,168 $ (21,538 ) $ 16,630 Customer relationships 20,582 (10,192 ) 10,390 16,382 (7,893 ) 8,489 Non-compete agreements 804 (594 ) 210 804 (462 ) 342 Trade names and patents 1,006 (374 ) 632 806 (264 ) 542 Order backlog 400 (130 ) 270 200 (17 ) 183 In-process research and development 900 — 900 900 — 900 $ 69,760 $ (35,798 ) $ 33,962 $ 57,260 $ (30,174 ) $ 27,086 Amortization of intangible assets expense was $2,917 and $2,109 for the three months ended June 30, 2015 and 2014 , respectively, and $5,624 and $4,069 for the six months ended June 30, 2015 and 2014, respectively. Future estimated amortization of intangible assets expense as of June 30, 2015 are presented below: Year ending December 31, 2015, remainder $ 5,637 2016 9,288 2017 5,944 2018 5,348 2019 3,095 Thereafter 4,650 $ 33,962

Fair Value Measurements and Inv

Fair Value Measurements and Investments (Notes)	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value and Investments Disclosures	Fair Value Measurements and Investments Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (i.e., the “exit price”) in an orderly transaction between market participants at the measurement date. A hierarchy for inputs used in measuring fair value has been defined to minimize the use of unobservable inputs by requiring the use of observable market data when available. Observable inputs are inputs that market participants would use in pricing the asset or liability based on active market data. Unobservable inputs are inputs that reflect the Company’s assumptions about the assumptions market participants would use in pricing the asset or liability based on the best information available in the circumstances. The fair value hierarchy prioritizes the inputs into three broad levels: • Level 1: Quoted (unadjusted) prices in active markets for identical assets or liabilities. The Company’s Level 1 assets generally consist of money market funds. • Level 2: Observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets or liabilities in active markets; quoted prices for identical or similar assets or liabilities in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the asset or liability. The Company’s Level 2 assets and liabilities generally consist of corporate debt securities, commercial papers, certificates of deposit and convertible senior notes. • Level 3: Unobservable inputs to the valuation methodology that are supported by little or no market activity and that are significant to the measurement of the fair value of the assets or liabilities. Level 3 assets and liabilities include those whose fair value measurements are determined using pricing models, discounted cash flow methodologies or similar valuation techniques, as well as significant management judgment or estimation. The following tables summarize, for each category of assets or liabilities carried at fair value, the respective fair value as of June 30, 2015 and December 31, 2014 and the classification by level of input within the fair value hierarchy: Balance as of Quoted Prices Significant Unobservable Assets Cash equivalents: Money market funds $ 386,872 $ 386,872 $ — $ — Short-term investments: Corporate debt securities 8,510 — 8,510 — Total financial assets $ 395,382 $ 386,872 $ 8,510 $ — Balance as of Quoted Prices Significant Unobservable Assets Cash equivalents: Money market funds $ 139,644 $ 139,644 $ — $ — Short-term investments: Corporate debt securities 31,651 — 31,651 — Commercial papers 2,998 — 2,998 — Total financial assets $ 174,293 $ 139,644 $ 34,649 $ — Based on quoted market prices as of June 30, 2015 , the fair values of the 0.75% and 1.25% Convertible Senior Notes were approximately $340,694 and $248,812 , respectively, determined using Level 2 inputs as they are not actively traded in markets. The carrying amounts of the Company's cash equivalents, accounts receivable, accounts payable and accrued liabilities approximate their fair values due to their short maturities. Based on borrowing rates that are available to the Company for loans with similar terms and consideration of the Company's credit risk, the carrying value of the notes payable approximates their fair values using Level 2 inputs. Investments The cost and fair value of the Company’s cash and cash equivalents and available-for-sale investments as of June 30, 2015 and December 31, 2014 were as follows: June 30, 2015 Cost Basis Unrealized Gains Unrealized Losses Fair Value Cash and cash equivalents: Cash $ 15,272 $ — $ — $ 15,272 Money market funds 386,872 — — 386,872 Total $ 402,144 $ — $ — $ 402,144 Short-term investments: Corporate debt securities $ 8,512 $ — $ (2 ) $ 8,510 Total $ 8,512 $ — $ (2 ) $ 8,510 December 31, 2014 Cost Basis Unrealized Gains Unrealized Losses Fair Value Cash and cash equivalents: Cash $ 40,693 $ — $ — $ 40,693 Money market funds 139,644 — — 139,644 Total $ 180,337 $ — $ — $ 180,337 Short-term investments: Corporate debt securities $ 31,678 $ — $ (27 ) $ 31,651 Certificate of deposit 2,998 — — 2,998 Total $ 34,676 $ — $ (27 ) $ 34,649 As of June 30, 2015 and December 31, 2014 , all investments mature in less than one year. Estimated fair values for marketable securities are based on quoted market prices for the same or similar instruments.

Commitments and Contingencies (

Commitments and Contingencies (Notes)	6 Months Ended
	Jun. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Operating Leases The Company leases certain of its facilities under noncancellable operating leases with various expiration dates through May 2025. Premises rent expense was $951 and $860 for the three months ended June 30, 2015 and 2014 , respectively, and $1,818 and $1,398 for the six months ended June 30, 2015 and 2014, respectively. Capital Leases In July 2012, the Company entered into two lease agreements to lease certain office equipment with expiration dates in July and October 2015. These leases bear an annual interest rate of 4.5% and are secured by fixed assets used in the Company's office locations. At June 30, 2015 , future annual minimum lease payments under noncancellable operating and capital leases were as follows: Capital Operating Year ending December 31, 2015, remainder $ 2 $ 4,032 2016 — 7,343 2017 — 3,915 2018 — 3,816 2019 — 3,643 Thereafter — 1,291 Total minimum lease payments 2 $ 24,040 Less: Amount representing interest — Present value of capital lease obligations 2 Less: current portion (2 ) Long-term portion of capital lease obligations $ — Contingencies Under the indemnification provisions of the Company's customer agreements, the Company agrees to indemnify and defend and hold harmless its customers against, among other things, infringement of any patent, trademark or copyright under any country's laws or the misappropriation of any trade secret arising from the customers' legal use of the Company's solutions. The exposure to the Company under these indemnification provisions is generally limited to the total amount paid by the customers under the applicable customer agreement. However, certain indemnification provisions potentially expose the Company to losses in excess of the aggregate amount paid to the Company by the customer under the applicable customer agreement. To date, there have been no claims against the Company or its customers pursuant to these indemnification provisions. Legal Contingencies From time to time, the Company may be involved in legal proceedings and subject to claims in the ordinary course of business. On December 16, 2013, Finjan, Inc. sued the Company and its wholly-owned subsidiary, Armorize Technologies, Inc., in the United States District Court, Northern District of California for alleged patent infringement of a variety of its patents, demanding preliminary and permanent injunctive relief, and unspecified damages. The Company and Armorize filed an answer to the complaint on February 10, 2014. On April 15, 2014, Finjan’s initial disclosures in the lawsuit alleged approximately $13,500 in damages, but provided no basis or facts in support of this sum. On April 2, 2015, the court ordered that the claims construction hearing be held in June 2015 and trial be set for March 2016, subject to alteration only upon a showing of good cause. On April 2, 2015, the court ordered that the claims construction hearing be held in June 2015 and trial be set for March 2016, subject to later adjustment or delay. On April 2, 2015, the court also ordered in part that Finjan amend its infringement contentions to comply with the Patent Local Rules by April 23, 2015. On April 23, 2015, Finjan amended its infringement contentions. On June 24, 2015, the court held the claims construction hearing in this matter and the court’s ruling is now pending. Based on the state of the infringement contentions and evaluation of the facts available at this time, the amount or range of reasonable possible losses to which the Company or Armorize is exposed cannot be estimated and the ultimate resolution of this matter and the associated financial statement impact, if any, remains uncertain at this time. The Company and Armorize intend to vigorously defend the lawsuit. Intellectual property litigation is subject to inherent uncertainties, and there can be no assurance that the expenses associated with defending any litigation or the resolution of this dispute would not have a material adverse impact on the Company's results of operations or cash flows. Regardless of the outcome, such proceedings and claims can have an adverse impact on the Company because of defense and settlement costs, diversion of resources and other factors, and there can be no assurances that favorable outcomes will be obtained.

Convertible Senior Notes (Notes

Convertible Senior Notes (Notes)	6 Months Ended
	Jun. 30, 2015
Convertible Senior Notes [Abstract]
Convertible Senior Notes	Convertible Senior Notes 0.75% Convertible Senior Notes due June 2020 On June 17, 2015 , the Company issued $200,000 principal amount of 0.75% Convertible Senior Notes (the "0.75% Notes") due 2020 in a private offering to qualified institutional buyers ("Holders") pursuant to Rule 144A under the Securities Act of 1944 (the "Exchange Act"), as amended. The initial Holders of the 0.75% Notes also had an option to purchase an additional $30,000 in principal amount which was exercised in full. The net proceeds after the agent's discount and issuance costs of $6,581 from the 0.75% Notes offering were approximately $223,419 . The Company will use the net proceeds for working capital and general corporate purposes, which may include funding the Company's operations, capital expenditures, potential acquisitions of businesses, products or technologies believed to be of strategic importance. The 0.75% Notes bear interest at 0.75% per year, payable semi-annually in arrears every June 15 and December 15, beginning on December 15, 2015. The 0.75% Notes are unsecured and rank senior in right of payment to any indebtedness expressly subordinated in right of payment to the 0.75% Notes. They rank equally with the Company's other existing and future unsecured indebtedness that is not subordinated and are structurally subordinated to any current or future secured indebtedness to the extent of the value of the assets securing the indebtedness and other liabilities of the Company's subsidiaries. The initial conversion rate is 12.3108 shares of the Company’s common stock per $1 principal amount of notes which equates to 2,831 shares of common stock, or a conversion price equivalent of $81.23 per share of common stock. Throughout the term of the 0.75% Notes, the conversion rate may be adjusted upon the occurrence of certain events, such as the payment of cash dividends or issuance of stock warrants. The 0.75% Notes mature on June 15, 2020 , unless repurchased, redeemed or converted in accordance with their terms prior to such date. At the Company's option, on or after June 20, 2018 , the Company will be able to redeem all or a portion of the 0.75% Notes at 100% of the principal amount, plus any accrued and unpaid interest, under certain conditions. The Company may redeem the 0.75% Notes in shares of the Company’s common stock, cash, or some combination of each. Prior to December 15, 2019 , the 0.75% Notes will be convertible at the option of the Holders only upon the satisfaction of certain conditions and during certain periods if any of the following events occur: • during the calendar quarter commencing after September 30, 2015, if the last reported sale price of the Company's common stock is greater than or equal to 130% of the applicable conversion price on each such trading day for at least 20 trading days (whether or not consecutive) during the period of 30 consecutive trading days ending on the last trading day of the preceding calendar quarter; • during the 5 business day period after any 5 consecutive trading day period in which the trading price, as defined, per $1 principal amount of the 0.75% Notes for each trading day of such measurement period was less than 98% of the product of the last reported sale price of the Company's common stock and the applicable conversion rate on each such trading day; • upon a notice of redemption by the Company; or • upon the occurrence of specified corporate transactions. Subsequent to December 15, 2019 , Holders may convert their 0.75% Notes at the applicable conversion rate at any time prior to the close of business on the second scheduled trading day immediately preceding the maturity date. Holders of the 0.75% Notes also have the right to require the Company to repurchase all or a portion of the 0.75% Notes at 100% of the principal amount, plus accrued and unpaid special interest, if any, upon the occurrence of certain fundamental changes to the Company. In accordance with the authoritative accounting guidance, the Company allocated the total amount of the 0.75% Notes into liability and equity components. The carrying value of the liability component at issuance was calculated as the present value of its cash flows using a discount rate of 6.5% based on the a blended rate between the yield rate for a Moody's B1 rating and the average debt rate for comparable convertible transactions from similar companies. The difference between the 0.75% Notes principal and the carrying value of the liability component, representing the value of conversion premium assigned to the equity component, was recorded as an increase to additional paid in capital and as a debt discount on the issuance date. The equity component is being accreted using the effective interest rate method over the period from the issuance date through June 15, 2020 as a non-cash charge to interest expense. The amount recorded to additional paid in capital is not remeasured as long as it continues to meet the conditions for equity classification. Upon issuance of the 0.75% Notes, the Company recorded $174,359 as debt and $55,641 as additional paid in capital within stockholders' equity. Additionally, the debt discount and issuance costs were bifurcated into debt issuance costs (attributable to the liability component) and equity issuance costs (attributable to the equity component) based on their relative fair values. The equity issuance costs of $1,592 were recorded as a decrease to additional paid-in capital at the issuance date. 1.25% Convertible Senior Notes due December 2018 On December 11, 2013 , the Company issued $175,000 principal amount of 1.25% Convertible Senior Notes (the "1.25% Notes," and together with the 0.75% Notes, the “Notes”) due 2018 in a private offering to qualified institutional buyers ("Holders") pursuant to Rule 144A under the Exchange Act. The initial Holders of the 1.25% Notes also had an option to purchase an additional $26,250 in principal amount which was exercised in full. The net proceeds after the agent's discount and issuance costs of $5,803 from the 1.25% Notes offering were approximately $195,446 . The Company uses the net proceeds for working capital and general corporate purposes, which may include funding the Company's operations, capital expenditures, potential acquisitions of businesses, products or technologies believed to be of strategic importance. The 1.25% Notes bear interest at 1.25% per year, payable semi-annually in arrears every June 15 and December 15, beginning on June 15, 2014. The 1.25% Notes are unsecured and rank senior in right of payment to any indebtedness expressly subordinated in right of payment to the 1.25% Notes. They rank equally with the Company's other existing and future unsecured indebtedness that is not subordinated and are structurally subordinated to any current or future secured indebtedness to the extent of the value of the assets securing the indebtedness and other liabilities of the Company's subsidiaries. The initial conversion rate is 25.6271 shares of the Company’s common stock per $1 principal amount of notes which equates to 5,158 shares of common stock, or a conversion price equivalent of $39.02 per share of common stock. Throughout the term of the 1.25% Notes, the conversion rate may be adjusted upon the occurrence of certain events, such as the payment of cash dividends or issuance of stock warrants. The 1.25% Notes mature on December 15, 2018 , unless repurchased, redeemed or converted in accordance with their terms prior to such date. At the Company's option, on or after December 20, 2016 , the Company will be able to redeem all or a portion of the 1.25% Notes at 100% of the principal amount, plus any accrued and unpaid interest, under certain conditions. The Company may redeem the 1.25% Notes in shares of the Company’s common stock, cash, or some combination of each. Prior to June 15, 2018 , the 1.25% Notes will be convertible at the option of the Holders only upon the satisfaction of certain conditions and during certain periods if any of the following events occur: • during the calendar quarter commencing after March 31, 2014, if the last reported sale price of the Company's common stock is greater than or equal to 130% of the applicable conversion price on each such trading day for at least 20 trading days (whether or not consecutive) during the period of 30 consecutive trading days ending on the last trading day of the preceding calendar quarter; • during the 5 business day period after any 5 consecutive trading day period in which the trading price, as defined, per $1 principal amount of the 1.25% Notes for each trading day of such measurement period was less than 98% of the product of the last reported sale price of the Company's common stock and the applicable conversion rate on each such trading day; • upon a notice of redemption by the Company; or • upon the occurrence of specified corporate transactions. Subsequent to June 15, 2018 , Holders may convert their 1.25% Notes at the applicable conversion rate at any time prior to the close of business on the second scheduled trading day immediately preceding the maturity date. Holders of the 1.25% Notes also have the right to require the Company to repurchase all or a portion of the 1.25% Notes at 100% of the principal amount, plus accrued and unpaid special interest, if any, upon the occurrence of certain fundamental changes to the Company. In accordance with the authoritative accounting guidance, the Company allocated the total amount of the 1.25% Notes into liability and equity components. The carrying value of the liability component at issuance was calculated as the present value of its cash flows using a discount rate of 6.5% based on the a blended rate between the yield rate for a Moody's B1-rating and the average debt rate for comparable convertible transactions from similar companies. The difference between the 1.25% Notes principal and the carrying value of the liability component, representing the value of conversion premium assigned to the equity component, was recorded as an increase to additional paid in capital and as a debt discount on the issuance date. The equity component is being accreted using the effective interest rate method over the period from the issuance date through December 15, 2018 as a non-cash charge to interest expense. The amount recorded to additional paid in capital is not remeasured as long as it continues to meet the conditions for equity classification. Upon issuance of the 1.25% Notes, the Company recorded $156,672 as debt and $44,578 as additional paid in capital within stockholders' equity. Additionally, the discount and issuance costs were bifurcated into debt issuance costs (attributable to the liability component) and equity issuance costs (attributable to the equity component) based on their relative fair values. The equity issuance costs of $1,285 were recorded as a decrease to additional paid-in capital at the issuance date. The following table presents the carrying values of all Convertible Notes as of June 30, 2015 : 0.75% Notes 1.25% Notes TOTAL Liability component: Principal $ 230,000 $ 201,250 $ 431,250 Less: debt discount and issuance costs, net of amortization (60,231 ) (35,291 ) (95,522 ) Net carrying amount $ 169,769 $ 165,959 $ 335,728 Equity component (1) $ 54,049 $ 43,293 $ 97,342 (1) Recorded in the accompanying Condensed Consolidated Balance Sheets as additional paid-in capital, net of the $2,877 issuance costs. For the three and six months ended June 30, 2015 and 2014 , the Company incurred the following interest expense related to the Notes: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Interest expense related to contractual interest coupon $ 691 624 $ 1,320 1,253 Amortization of debt discount and issuance costs 2,696 2,173 4,962 4,316 $ 3,387 $ 2,797 $ 6,282 $ 5,569

Debt (Notes)

Debt (Notes)	6 Months Ended
	Jun. 30, 2015
Debt Disclosure [Abstract]
Debt	Debt Equipment Financing Loans The Company entered into an equipment loan agreement with Silicon Valley Bank in April 2011 for an aggregate loan principal amount of $6,000 . Interest on the advances was equal to prime rate plus 0.5% . The Company had the ability to draw down on this equipment line through April 19, 2012. Each drawn amount was due 48 months after funding. The outstanding balance of equipment financing loans was fully repaid in the second quarter of 2015. Interest expense was $1 and $23 , respectively, for the three months ended June 30, 2015 and 2014 , and $5 and $51 , respectively, for the six months ended June 30, 2015 and 2014 .

Common Stock (Notes)

Common Stock (Notes)	6 Months Ended
	Jun. 30, 2015
Equity [Abstract]
Stockholders' Equity	Common Stock As of June 30, 2015 , the Company is authorized to issue two classes of stock totaling 205,000 shares, of which 5,000 are designated as preferred stock and 200,000 are designated common stock, each with a par value of $0.0001 per share. Number of shares of common stock reserved for future issuance was as follows: As of As of December 31, 2015 2014 Shares available for future grant under the stock plans 5,560 4,330 Options outstanding under stock plans 4,620 5,288 Shares available for future issuance under ESPP 1,226 926 Common stock issuable settlement of outstanding restricted stock units 3,160 2,934 Common stock issuable upon conversion of the convertible senior notes 7,989 5,158 Total shares reserved 22,555 18,636

Stock Equity Plans (Notes)

Stock Equity Plans (Notes)	6 Months Ended
	Jun. 30, 2015
Equity Incentive Plans Held [Line Items]
Stock Equity Plans	Stock Equity Plans Stock-Based Compensation Plans On March 30, 2012, the Board of Directors and the Company’s stockholders approved the 2012 Equity Incentive Plan (the "2012 Plan"), which became effective in April 2012. The Company has two equity incentive plans: the Company’s 2002 stock option plan (the “2002 Plan”) and the 2012 Plan. Upon the IPO, all shares that were reserved under the 2002 Plan but not issued, and shares issued but subsequently returned to the plan through forfeitures, cancellations and repurchases became part of the 2012 Plan and no further shares will be granted pursuant to the 2002 Plan. All outstanding stock awards under the 2002 and 2012 Plans will continue to be governed by their existing terms. Under the 2012 Plan, the Company has the ability to issue incentive stock options (“ISOs”), nonstatutory stock options (“NSOs”), restricted stock awards, stock bonus awards, stock appreciation rights ("SARs"), restricted stock units ("RSUs"), and performance stock units ("PSUs"). The 2012 Plan also allows direct issuance of common stock to employees, outside directors and consultants at prices equal to the fair market value at the date of grant of options or issuance of common stock. Additionally, the 2012 Plan provides for the grant of performance cash awards to employees, directors and consultants. The Company has the right to repurchase any unvested shares (at the option exercise price) of common stock issued directly or under option exercises. The right of repurchase generally expires over the vesting period. Stock bonus and other liability awards are accounted for as liability-classified awards, because the obligations are based predominantly on fixed monetary amounts that are generally known at the inception of the obligation, to be settled with a variable number of shares of the Company's common stock. Under the 2002 and 2012 Plans, the term of an option grant shall not exceed ten years from the date of its grant and options generally vest over a three to four -year period, with vesting on a monthly or annual interval. Under the 2012 Plan, 20,316 shares of common stock are reserved for issuance to eligible participants. As of June 30, 2015 , 5,560 shares were available for future grant. Restricted stock awards generally vest over a four -year period. The number of shares available for grant and issuance under the 2012 Plan will be increased automatically on each January 1 of 2013 through 2016 by an amount equal to 5% of the Company's shares outstanding on the immediately preceding December 31, but not to exceed 3,724 shares, unless the Board of Directors, in its discretion, determines to make a smaller increase. Stock Options The fair value of options granted is estimated on the grant date using the Black-Scholes option valuation model. This valuation model for stock-based compensation expense requires the Company to make assumptions and judgments about the variables used in the calculation, including the expected term (weighted-average period of time that the options granted are expected to be outstanding), the volatility of the common stock price and the assumed risk-free interest rate. The Company recognizes stock-based compensation expense for only those shares expected to vest over the requisite service period of the award. The Company determines its estimated forfeiture rate based on an analysis of its actual forfeitures and will continue to evaluate the appropriateness of the forfeiture rate based on recent forfeiture activity and expected future employee turnover, if any. Changes in the estimated forfeiture rate can have a significant effect on reported stock-based compensation expense, as the cumulative effect of adjusting the rate for all expense is recognized in the period the forfeiture estimate is changed. No compensation cost is recorded for options that do not vest and the compensation cost from vested options, whether forfeited or not, is not reversed. The weighted average fair value of stock options granted to employees was $28.23 and $19.51 during the three months ended June 30, 2015 and 2014 , respectively, and $27.81 and $19.88 during the six months ended June 30, 2015 and 2014, respectively. The fair values were estimated on the grant dates using the Black-Scholes option-pricing model with the following weighted-average assumptions: Three Months Ended June 30, Six Months Ended 2015 2014 2015 2014 Expected life (in years) 5.31 - 6.08 5.31 - 6.08 5.31 - 6.08 5.31 - 6.08 Volatility 50 % 54% - 58% 50% - 52% 54% - 58% Risk-free interest rate 1.7 % 1.8% - 1.9% 1.6% - 1.7% 1.8% - 1.9% Dividend yield — % — % — % — % The estimate for expected life of options granted reflects the midpoint of the vesting term and the contractual life computed utilizing the simplified method as allowed by the SEC staff. The Company does not have significant historical share option exercise experience and hence considers the expected term assumption calculated using the simplified method to be reasonable. Since the Company's stock has been publicly traded for a limited time, the stock volatility assumptions represent an estimate of the historical volatilities of the common stock of a group of publicly-traded peer companies that operate in a similar industry. The estimate was determined based on the average historical volatilities of these peer companies. The risk-free interest rate used was the Federal Reserve Bank's constant maturities interest rate commensurate with the expected life of the options in effect at the time of the grant. The expected dividend yield was zero, as the Company does not anticipate paying a dividend within the relevant time frame. The Company realized no income tax benefit from stock option exercises in each of the periods presented due to recurring losses and the valuation allowances for deferred tax assets. Stock option activity under the Plan is as follows: Shares subject to Options Outstanding Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value Balance at December 31, 2014 5,288 $ 11.06 6.31 $ 196,608 Options granted 259 56.68 Options exercised (843 ) 7.73 Options forfeited and canceled (84 ) 19.36 Balance at June 30, 2015 4,620 $ 14.08 6.11 $ 229,116 The total intrinsic value of options exercised was $40,237 and $32,192 for the six months ended June 30, 2015 and 2014 , respectively. Total cash proceeds from such option exercises were $6,520 and $6,465 for the six months ended June 30, 2015 and 2014 , respectively. The fair value of option grants that vested was $5,896 and $5,870 for the six months ended June 30, 2015 and 2014 , respectively. As of June 30, 2015 , the Company had unamortized stock-based compensation expense of $16,654 related to stock options, that will be recognized net of forfeitures over the average remaining vesting term of the options of 2.14 years. Restricted Stock and Performance Stock Units A following table summarized the activity of RSUs and PSUs: RSUs and PSUs Outstanding Number of Shares Granted Fair Value Per Unit Awarded and unvested at December 31, 2014 2,934 $ 37.45 Awards granted 801 57.37 Awards vested (459 ) 35.64 Awards forfeited (116 ) 34.82 Awarded and unvested at June 30, 2015 3,160 $ 42.87 As of June 30, 2015 , there was $82,846 of unamortized stock-based compensation expense related to unvested RSUs, which is expected to be recognized over a weighted average period of 3.27 years. The Company granted 172 and 17 PSUs in the six months ended June 30, 2015 and 2014, respectively. The PSU vesting conditions were based on individual performance targets. Unamortized expense was $4,046 as of June 30, 2015, net of estimated forfeitures. Stock Bonus and Other Liability Awards The total accrued liability for the stock bonus awards was $1,459 and $1,771 as of June 30, 2015 and December 31, 2014, respectively. 27 and 22 shares of common stock earned under the stock bonus program were issued during the six months ended June 30, 2015 and 2014, respectively. Stock based compensation expense related to stock bonus program were $1,459 and $988 for the six months ended June 30, 2015 and 2014, respectively. In March 2015, the Company issued liability awards with a fair value of $6,885 , which vest over three years period and are subject to continuous service and other conditions. The liability awards will be settled with a variable number of shares of the Company's common stock. The Company recognized $729 of stock-based compensation expense related to these liability awards in the six months ended June 30, 2015. Employee Stock Purchase Plan On March 30, 2012, the Board of Directors and the Company’s stockholders approved the 2012 Employee Stock Purchase Plan (the "ESPP"), which became effective in April 2012. A total of 745 shares of the Company's common stock were initially reserved for future issuance under the ESPP. The number of shares reserved for issuance under the ESPP will increase automatically on January 1 of each of the first eight years commencing with 2013 by the number of shares equal to 1% of the Company's shares outstanding on the immediately preceding December 31, but not to exceed 1,490 shares, unless the Board of Directors, in its discretion, determines to make a smaller increase. As of June 30, 2015 , there were 1,226 shares of the Company's common stock available for future issuance under the ESPP. As of June 30, 2015 , the Company expects to recognize $882 of the total unamortized compensation cost related to employee purchases under the ESPP over a weighted average period of 0.38 years. Restricted Stock The Company granted 54 shares of restricted stock in the fourth quarter of 2014 to certain key employees with the total fair value of $2,357 and two-year cliff vesting in 2016. The Company recognized $589 of stock based compensation expense in the six months ended June 30, 2015, and as of June 30, 2015, there was $1,572 of unamortized stock-based compensation expense related to the unvested shares of restricted stock. The shares of restricted stock are subject to forfeiture if employment terminates prior to the lapse of the restrictions, and are expensed over the vesting period. They are considered issued and outstanding shares of the Company at the grant date and have the same rights as other shares of common stock.

Net Loss per Share (Notes)

Net Loss per Share (Notes)	6 Months Ended
	Jun. 30, 2015
Earnings Per Share [Abstract]
Net Loss per Share	Net Loss per Share Basic net loss per share of common stock is calculated by dividing the net loss by the weighted‑average number of shares of common stock outstanding for the period. The weighted‑average number of shares of common stock used to calculate basic net loss per share of common stock excludes those shares subject to repurchase related to stock options or restricted stock that were exercised or issued prior to vesting as these shares are not deemed to be issued for accounting purposes until they vest. Diluted net loss per share of common stock is computed by dividing the net loss using the weighted‑average number of shares of common stock, excluding common stock subject to repurchase, and, if dilutive, potential shares of common stock outstanding during the period. Basic and diluted net loss per common share was the same for all periods presented as the impact of all potentially dilutive securities outstanding was anti-dilutive. The following table presents the potentially dilutive common shares outstanding that were excluded from the computation of diluted net loss per share for the periods presented because including them would have been anti-dilutive: As of June 30, 2015 2014 Stock options to purchase common stock 4,620 6,482 Restricted stock units 3,160 2,236 Employee stock purchase plan 78 106 Common stock subject to repurchase 54 — Bonus and other liability awards 158 — 1.25% Convertible senior notes 5,158 5,158 0.75% Convertible senior notes 2,831 — Total 16,059 13,982

Segment Reporting (Notes)

Segment Reporting (Notes)	6 Months Ended
	Jun. 30, 2015
Segment Reporting [Abstract]
Segment Reporting	Segment Reporting Operating segments are reported in a manner consistent with the internal reporting supported and defined by the components of an enterprise about which separate financial information is available, provided and is evaluated regularly by the chief operating decision maker in deciding how to allocate resources and in assessing performance. The Company’s chief operating decision maker is its Chief Executive Officer. The Company’s Chief Executive Officer reviews financial information presented on a consolidated basis. We have one business activity, and there are no segment managers who are held accountable for operations, operating results and plans for levels or components below the consolidated unit level. Accordingly, we have determined that we have one operating and reportable segment. The following set forth total revenue by solutions offered by the Company and geographic area. Revenue by geographic area is based upon the billing address of the customer: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Total revenue by solution: Privacy, Protection and Security $ 50,431 $ 35,549 $ 95,802 $ 68,152 Archiving and Governance 13,115 10,849 25,507 20,950 Total revenue $ 63,546 $ 46,398 $ 121,309 $ 89,102 Three Months Ended June 30, Six Months Ended 2015 2014 2015 2014 Total revenue: United States $ 52,701 $ 38,012 $ 99,755 $ 73,229 Rest of world 10,845 8,386 21,554 15,873 Total revenue $ 63,546 $ 46,398 $ 121,309 $ 89,102 Long-lived assets by geographic area are presented below: As of June 30, As of December 31, 2015 2014 Long-lived assets: United States $ 23,314 $ 15,974 Rest of world 3,460 2,744 Total long‑lived assets $ 26,774 $ 18,718

Income Taxes (Notes)

Income Taxes (Notes)	6 Months Ended
	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company’s quarterly provision for income taxes is based on an estimated effective annual income tax rate. The Company’s quarterly provision for income taxes also includes the tax impact of certain unusual or infrequently occurring items, if any, including changes in judgment about valuation allowances and effects of changes in tax laws or rates, in the interim period in which they occur. Income tax expense for the three and six months ended June 30, 2015 was $112 and $274 on pre-tax losses of $24,861 and $46,372 , respectively. The Company recognized income tax expense of $147 and $291 for the three and six months ended June 30, 2014 on pre-tax losses of $14,978 and $29,229 , respectively. The income tax rate for the three and six months ended June 30, 2015 and 2014 varies from the United States statutory income tax rate primarily due to valuation allowances in the United States whereby pre-tax losses and gains do not result in the recognition of corresponding income tax benefits and expenses. The Company's effective tax rate for the six months ended June 30, 2015 decreased to negative 0.6% from negative 1.0% for the same prior year period. The Company reviews the likelihood that it will realize the benefit of its deferred tax assets and, therefore, the need for valuation allowances, on a quarterly basis. There is no corresponding income tax benefit recognized with respect to losses incurred and no corresponding income tax expense recognized with respect to earnings generated in jurisdictions with a valuation allowance. This causes variability in the Company’s effective tax rate. The Company intends to maintain the valuation allowances until it is more likely than not that the net deferred tax assets will be realized. As of June 30, 2015, the Company's gross uncertain tax benefits totaled $4,268 , excluding related accrued interest and penalties of $234 . As of June 30, 2015, $1,306 of the Company's uncertain tax benefits, including related accrued interest and penalties, would affect the effective tax rate if recognized. During the six months ended June 30, 2015, the Company's gross uncertain tax benefits increased $42 . The increase is comprised of $79 increase for tax positions taken in the current period offset by an $18 increase for tax positions taken in prior periods and a $55 decrease related to statute of limitation expirations. The Company is not currently under audit by the IRS or any similar taxing authority in any other material jurisdiction. The Company believes it has recorded all appropriate provisions for all jurisdictions and open years. However, the Company can give no assurance that taxing authorities will not propose adjustments that would increase its tax liabilities.

Subsequent events (Notes)

Subsequent events (Notes)	6 Months Ended
	Jun. 30, 2015
Subsequent Event [Member]
Subsequent Event [Line Items]
Subsequent Events [Text Block]	Subsequent events In July 2015 , the Company acquired certain assets of Marble Security, Inc. (“Marble”) for a purchase price of $8,500 . The Marble mobile security technology proactively removes malicious mobile applications by leveraging its tight integration with the leading enterprise mobility management (EMM) platforms, including MobileIron and AirWatch by VMware. The acquisition extends the Company’s proven threat intelligence and advanced threat protection for email and social media security into the realm of mobile devices. Management is currently in the process of valuing the assets acquired and liabilities assumed associated with this asset purchase.

The Company and Summary of Si20

The Company and Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All significant inter-company transactions and balances have been eliminated in consolidation. The Company acquired one company in the six months ended June 30, 2015 and two companies in the year ended December 31, 2014. These acquisitions are more fully described in note 2, "Acquisitions". The consolidated financial statements include the results of operations from these business combinations from their date of acquisition. The accompanying condensed consolidated financial statements have been prepared in accordance with United States generally accepted accounting principles (“GAAP”), pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Certain information and note disclosures have been condensed or omitted pursuant to such rules and regulations. The accompanying Condensed Consolidated Balance Sheet as of December 31, 2014 is derived from audited financial statements as of that date but does not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements. The unaudited condensed consolidated financial statements have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the periods presented. The results of operations for the three and six months ended June 30, 2015 are not necessarily indicative of the results to be expected for the year ending December 31, 2015 or for other interim periods or for future years. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and accompanying notes for the year ended December 31, 2014 included in the Company’s Annual Report on Form 10-K filed with the SEC. The Company’s significant accounting policies are described in note 1 to those audited consolidated financial statements.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America 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 expenses during the reporting period. Actual results could differ from those estimates and such difference may be material to the financial statements.
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill represents the excess of the purchase price of the acquired enterprise over the fair value of identifiable assets acquired and liabilities assumed. The Company performs an annual goodwill impairment test during the fourth quarter of a calendar year and more frequently if an event or circumstances indicates that impairment may have occurred. For the purposes of impairment testing, the Company has determined that it has one operating segment and one reporting unit. The Company performs a two-step impairment test of goodwill whereby the fair value of the reporting unit is compared to its carrying value. If the fair value of the reporting unit exceeds the carrying value of the net assets assigned to that unit, goodwill is not considered impaired and further testing is not required. If the carrying value of the net assets assigned to the reporting unit exceeds the fair value of the reporting unit, then the Company must perform the second step of the impairment test in order to determine the implied fair value of the reporting unit’s goodwill. If the carrying value of a reporting unit’s goodwill exceeds its implied fair value, then impairment loss equal to the difference is recorded. The identification and measurement of goodwill impairment involves the estimation of the fair value of the Company. The estimate of fair value of the Company, based on the best information available as of the date of the assessment, is subjective and requires judgment, including management assumptions about expected future revenue forecasts and discount rates, changes in the overall economy, trends in the stock price and other factors. No impairment indicators were identified by the Company as of June 30, 2015 . Intangible assets consist of developed technology, customer relationships, non-compete arrangements, trademarks and patents, order backlog and in-process research and development asset. The values assigned to intangibles are based on estimates and judgments regarding expectations for success and life cycle of solutions and technologies acquired. Intangible assets are amortized on a straight-line basis over their estimated lives, which approximate the pattern in which the economic benefits of the intangible assets are consumed, as follows (in years): Low High Patents 4 5 Developed technology 3 7 Customer relationships 2 7 Non-compete agreements 2 4 Order backlog 1 2 Trade names and trademarks 1 5
Revenue Recognition	Revenue Recognition The Company derives its revenue primarily from two sources: (1) subscription revenue for rights related to the use of the security-as-a-service platform and (2) hardware, training and professional services revenue provided to customers related to their use of the platform. The Company records its revenues net of any value added or sales tax. Subscription revenue is derived from a subscription‑based enterprise licensing model with contract terms typically ranging from one to three years, and consists of (i) subscription fees from the licensing of the security-as-a-service platform, (ii) subscription fees for access to the on-demand elements of the platform and (iii) subscription fees for the right to access the Company’s customer support services. Revenue is recognized when all of the following criteria have been met: • Persuasive evidence of an arrangement exists; • Delivery has occurred or services have been rendered; • Sales price is fixed or determinable; and • Collectability is reasonably assured The Company's revenue arrangements typically include subscription services to its security-as-a-service platform. These hosted on demand service arrangements do not provide customers with the right to take possession of the software supporting the hosted services. Certain arrangements also include the sale of hardware appliances. Revenue from hardware appliances containing software components and hardware components that function together to deliver the hardware appliance's essential functionality is excluded from the scope of the industry specific revenue recognition guidance. The Company recognizes revenue from its hosted on demand services in accordance with general revenue recognition accounting guidance. Only revenue derived from the licensing of the software is recognized in accordance with the industry specific revenue guidance. The Company applies industry-specific software revenue recognition guidance to transactions involving the licensing of software, as well as related support, training, and other professional services. The Company has analyzed all of the elements included in its multiple element software arrangements and has determined that it does not have sufficient VSOE of fair value to allocate revenue to its subscription and software license agreements, support, training, and professional services. The Company defers all revenue under the software arrangement until the commencement of the subscription services and any associated professional services. Once the subscription services and the associated professional services have commenced, the entire fee from the arrangement is recognized ratably over the remaining period of the arrangement. If the professional services are essential to the functionality of the subscription, then the revenue recognition does not commence until such services are completed. When a sales arrangement contains multiple elements, such as hardware appliances, subscription services, customer support services, and/or professional services, the Company allocates revenue to each unit of accounting or element based on a selling price hierarchy. 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. When applying the relative selling price method, the Company determines the selling price for each deliverable using vendor-specific objective evidence (“VSOE”) of selling price. If VSOE does not exist, the Company uses third-party evidence (“TPE”) of selling price. If neither VSOE nor TPE of selling price exist for a deliverable, the Company uses its best estimate of selling price ("BESP") for that deliverable. Revenue allocated to each element is then recognized when the basic revenue recognition criteria are met for each element. The Company determines BESP for an individual element within a multiple element revenue arrangement using the same methods utilized to determine the selling price of an element sold on a standalone basis. The Company estimates the selling price for its subscription solutions by considering internal factors such as historical pricing practices and it estimates the selling price of hardware and other services using a cost plus model. Hardware appliance revenue is recognized upon shipment. Subscription and support revenue are recognized over the contract period commencing on the start date of the contract. Professional services and training, when sold with hardware appliances or subscription and support services, are accounted for separately when those services have standalone value. In determining whether professional services and training services can be accounted for separately from subscription and support services, the Company considers the following factors: availability of the services from other vendors, the nature of the services, and the dependence of the subscription services on the customer’s decision to buy the professional services. If professional services and training do not qualify for separate accounting, the Company recognizes the professional services and training ratably over the contract term of the subscription services. Delivery generally occurs when the hardware appliance is delivered to a common carrier freight on board shipping point by the Company or the hosted service has been activated and communicated to the customer accordingly. The Company’s fees are typically considered to be fixed or determinable at the inception of an arrangement and are negotiated at the outset of an arrangement, generally based on specific products and quantities to be delivered. In the event payment terms are provided that differ significantly from the Company's standard business practices, the fees are deemed to not be fixed or determinable and revenue is recognized as the fees become paid. The Company assesses collectability based on a number of factors, including credit worthiness of the customer and past transaction history of the customer. Through June 30, 2015 , the Company has not experienced significant credit losses.
Deferred Revenue	Deferred Revenue Deferred revenue primarily consists of billings or payments received in advance of revenue recognition from the sale of the Company’s subscription fees, training and professional services. Once the revenue recognition criteria are met, this revenue is recognized ratably over the term of the associated contract.
Comprehensive Income (Loss)	Comprehensive Loss Comprehensive loss includes all changes in equity that are not the result of transactions with stockholders. The Company’s comprehensive loss consists of its net loss and changes in unrealized gains (losses) from its available-for-sale investments. The Company had no material reclassifications out of accumulated other comprehensive loss into net loss for the three and six months ended June 30, 2015 and 2014 .
New Accounting Pronouncements	Recent Accounting Policies In April 2015, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update No. 2015-03, Interest - Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs (ASU 2015-03), which requires the Company to present such costs in the balance sheet as a direct deduction from the related debt liability rather than as an asset. Amortization of the costs will continue to be reported as interest expense. ASU 2015-03 is effective for fiscal years beginning after December 15, 2015 and interim periods within those fiscal years, with early adoption permitted. The Company early adopted this ASU effective during the second quarter of 2015 and has applied it retrospectively to all prior periods presented. Consequently, other long-term assets and convertible senior notes liabilities as of December 31, 2014 included in the consolidated balance sheet herein were reduced by $234 . There was no impact on the Company's results of operations or cash flows due to the adoption of this standard. In May 2014, the FASB issued Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers: Topic 606 (ASU 2014-09), to supersede nearly all existing revenue recognition guidance under U.S. GAAP. The core principle of ASU 2014-09 is to recognize revenues when promised goods or services are transferred to customers in an amount that reflects the consideration that is expected to be received for those goods or services. ASU 2014-09 defines a five step process to achieve this core principle and, in doing so, it is possible more judgment and estimates may be required within the revenue recognition process than required under existing U.S. GAAP including identifying performance obligations in the contract, estimating the amount of variable consideration to include in the transaction price and allocating the transaction price to each separate performance obligation. Originally, ASU 2014-09 was effective for the Company starting January 1, 2017 using either of two methods: (i) retrospective to each prior reporting period presented with the option to elect certain practical expedients as defined within ASU 2014-09; or (ii) retrospective with the cumulative effect of initially applying ASU 2014-09 recognized at the date of initial application and providing certain additional disclosures as defined per ASU 2014-09. In July 2015, the FASB voted to amend ASU 2014-09 by approving a one-year deferral of the effective date as well as providing the option to early adopt the standard on the original effective date. The Company is currently evaluating the timing and impact of the adoption of ASU 2014-09 on its consolidated financial statements.

The Company and Summary of Si21

The Company and Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Useful lives intangible assets [Table Text Block]	Intangible assets are amortized on a straight-line basis over their estimated lives, which approximate the pattern in which the economic benefits of the intangible assets are consumed, as follows (in years): Low High Patents 4 5 Developed technology 3 7 Customer relationships 2 7 Non-compete agreements 2 4 Order backlog 1 2 Trade names and trademarks 1 5

Acquisitions (Tables)

Acquisitions (Tables)	6 Months Ended
	Jun. 30, 2015
Business Acquisition [Line Items]
Schedule of purchase price [Table Text Block]	The following table summarizes the fair values of tangible and intangible assets acquired, liabilities assumed and goodwill: Estimated Estimated Current assets acquired $ 1,284 N/A Fixed assets acquired 174 N/A Liabilities assumed (448 ) N/A Deferred revenue assumed (700 ) N/A Holdback liability to the sellers (3,662 ) N/A Trade names 200 2 Customer relationships 4,200 7 Order Backlog 200 1 Developed technology 7,900 7 Goodwill 19,045 Indefinite $ 28,193 The following table summarizes the fair values of tangible assets acquired, liabilities assumed, intangible assets and goodwill: Fair Value Estimated Tangible assets acquired $ 14 N/A Liabilities assumed (1,267 ) N/A Customer relationships 100 5 Developed technology 5,500 5 Goodwill 18,384 Indefinite $ 22,731 The following table summarizes the fair values of tangible assets acquired, liabilities assumed, intangible assets and goodwill: Estimated Estimated Current assets acquired $ 1,340 N/A Fixed assets acquired 15 N/A Liabilities assumed (64 ) N/A Deferred revenue assumed (600 ) N/A Customer relationships 3,000 7 Order backlog 200 2 Developed technology 3,200 4 In-process research and development 900 N/A Deferred tax liability, net (792 ) N/A Goodwill 25,604 Indefinite $ 32,803
Pro forma information [Table Text Block]	Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Total revenue $ 63,335 $ 47,274 $ 121,104 $ 90,719 Net loss (24,923 ) (16,304 ) (48,116 ) (32,150 ) Basic and diluted net loss per share $ (0.63 ) $ (0.44 ) $ (1.23 ) $ (0.87 )

Goodwill and Intangible Asset23

Goodwill and Intangible Assets (Tables)	6 Months Ended
	Jun. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of goodwill [Table Text Block]	The goodwill activity and balances are presented below: Balance at December 31, 2014 $ 107,504 Add: Goodwill from acquisitions 19,395 Less: Other purchase price allocation adjustments to Goodwill (374 ) Balance at June 30, 2015 $ 126,525
Components of intangible assets excluding goodwill [Table Text Block]	Intangible assets, excluding goodwill, consisted of the following: June 30, 2015 December 31, 2014 Gross Accumulated Net Gross Accumulated Net Developed technology $ 46,068 $ (24,508 ) $ 21,560 $ 38,168 $ (21,538 ) $ 16,630 Customer relationships 20,582 (10,192 ) 10,390 16,382 (7,893 ) 8,489 Non-compete agreements 804 (594 ) 210 804 (462 ) 342 Trade names and patents 1,006 (374 ) 632 806 (264 ) 542 Order backlog 400 (130 ) 270 200 (17 ) 183 In-process research and development 900 — 900 900 — 900 $ 69,760 $ (35,798 ) $ 33,962 $ 57,260 $ (30,174 ) $ 27,086
Future estimated amortization costs of intangible assets [Table Text Block]	Amortization of intangible assets expense was $2,917 and $2,109 for the three months ended June 30, 2015 and 2014 , respectively, and $5,624 and $4,069 for the six months ended June 30, 2015 and 2014, respectively. Future estimated amortization of intangible assets expense as of June 30, 2015 are presented below: Year ending December 31, 2015, remainder $ 5,637 2016 9,288 2017 5,944 2018 5,348 2019 3,095 Thereafter 4,650 $ 33,962

Fair Value Measurements and I24

Fair Value Measurements and Investments (Tables)	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Fair value, by balance sheet grouping [Table Text Block]	The following tables summarize, for each category of assets or liabilities carried at fair value, the respective fair value as of June 30, 2015 and December 31, 2014 and the classification by level of input within the fair value hierarchy: Balance as of Quoted Prices Significant Unobservable Assets Cash equivalents: Money market funds $ 386,872 $ 386,872 $ — $ — Short-term investments: Corporate debt securities 8,510 — 8,510 — Total financial assets $ 395,382 $ 386,872 $ 8,510 $ — Balance as of Quoted Prices Significant Unobservable Assets Cash equivalents: Money market funds $ 139,644 $ 139,644 $ — $ — Short-term investments: Corporate debt securities 31,651 — 31,651 — Commercial papers 2,998 — 2,998 — Total financial assets $ 174,293 $ 139,644 $ 34,649 $ —
Fair value of cash and cash equivalents, and investments [Table Text Block]	The cost and fair value of the Company’s cash and cash equivalents and available-for-sale investments as of June 30, 2015 and December 31, 2014 were as follows: June 30, 2015 Cost Basis Unrealized Gains Unrealized Losses Fair Value Cash and cash equivalents: Cash $ 15,272 $ — $ — $ 15,272 Money market funds 386,872 — — 386,872 Total $ 402,144 $ — $ — $ 402,144 Short-term investments: Corporate debt securities $ 8,512 $ — $ (2 ) $ 8,510 Total $ 8,512 $ — $ (2 ) $ 8,510 December 31, 2014 Cost Basis Unrealized Gains Unrealized Losses Fair Value Cash and cash equivalents: Cash $ 40,693 $ — $ — $ 40,693 Money market funds 139,644 — — 139,644 Total $ 180,337 $ — $ — $ 180,337 Short-term investments: Corporate debt securities $ 31,678 $ — $ (27 ) $ 31,651 Certificate of deposit 2,998 — — 2,998 Total $ 34,676 $ — $ (27 ) $ 34,649

Commitments and Contingencies25

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Future annual minimum lease payments under noncancelable operating and capital leases [Table Text Block]	At June 30, 2015 , future annual minimum lease payments under noncancellable operating and capital leases were as follows: Capital Operating Year ending December 31, 2015, remainder $ 2 $ 4,032 2016 — 7,343 2017 — 3,915 2018 — 3,816 2019 — 3,643 Thereafter — 1,291 Total minimum lease payments 2 $ 24,040 Less: Amount representing interest — Present value of capital lease obligations 2 Less: current portion (2 ) Long-term portion of capital lease obligations $ —

Convertible Senior Notes (Table

Convertible Senior Notes (Tables)	6 Months Ended
	Jun. 30, 2015
Convertible Senior Notes [Abstract]
Schedule of liability and equity components of convertible debt [Table Text Block]	June 30, 2015 : 0.75% Notes 1.25% Notes TOTAL Liability component: Principal $ 230,000 $ 201,250 $ 431,250 Less: debt discount and issuance costs, net of amortization (60,231 ) (35,291 ) (95,522 ) Net carrying amount $ 169,769 $ 165,959 $ 335,728 Equity component (1) $ 54,049 $ 43,293 $ 97,342 (1) Recorded in the accompanying Condensed Consolidated Balance Sheets as additional paid-in capital, net of the $2,877 issuance costs.
Schedule of convertible note interest and accretion [Table Text Block]	For the three and six months ended June 30, 2015 and 2014 , the Company incurred the following interest expense related to the Notes: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Interest expense related to contractual interest coupon $ 691 624 $ 1,320 1,253 Amortization of debt discount and issuance costs 2,696 2,173 4,962 4,316 $ 3,387 $ 2,797 $ 6,282 $ 5,569

Common Stock (Tables)

Common Stock (Tables)	6 Months Ended
	Jun. 30, 2015
Equity [Abstract]
Number of shares of common stock reserved for future issuance [Table Text Block]	Number of shares of common stock reserved for future issuance was as follows: As of As of December 31, 2015 2014 Shares available for future grant under the stock plans 5,560 4,330 Options outstanding under stock plans 4,620 5,288 Shares available for future issuance under ESPP 1,226 926 Common stock issuable settlement of outstanding restricted stock units 3,160 2,934 Common stock issuable upon conversion of the convertible senior notes 7,989 5,158 Total shares reserved 22,555 18,636

Stock Equity Plans (Tables)

Stock Equity Plans (Tables)	6 Months Ended
	Jun. 30, 2015
Employee stock purchase plan
Valuation assumptions [Table Text Block]	The fair values were estimated on the grant dates using the Black-Scholes option-pricing model with the following weighted-average assumptions: Three Months Ended June 30, Six Months Ended 2015 2014 2015 2014 Expected life (in years) 5.31 - 6.08 5.31 - 6.08 5.31 - 6.08 5.31 - 6.08 Volatility 50 % 54% - 58% 50% - 52% 54% - 58% Risk-free interest rate 1.7 % 1.8% - 1.9% 1.6% - 1.7% 1.8% - 1.9% Dividend yield — % — % — % — %
Activity under stock option plan [Table Text Block]	Stock option activity under the Plan is as follows: Shares subject to Options Outstanding Number of Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value Balance at December 31, 2014 5,288 $ 11.06 6.31 $ 196,608 Options granted 259 56.68 Options exercised (843 ) 7.73 Options forfeited and canceled (84 ) 19.36 Balance at June 30, 2015 4,620 $ 14.08 6.11 $ 229,116
Summary of RSUs awarded and unvested under stock option plan [Table Text Block]	RSUs and PSUs Outstanding Number of Shares Granted Fair Value Per Unit Awarded and unvested at December 31, 2014 2,934 $ 37.45 Awards granted 801 57.37 Awards vested (459 ) 35.64 Awards forfeited (116 ) 34.82 Awarded and unvested at June 30, 2015 3,160 $ 42.87

Net Loss per Share (Tables)

Net Loss per Share (Tables)	6 Months Ended
	Jun. 30, 2015
Earnings Per Share [Abstract]
Schedule of antidilutive securities excluded from computation of earnings per share [Table Text Block]	The following table presents the potentially dilutive common shares outstanding that were excluded from the computation of diluted net loss per share for the periods presented because including them would have been anti-dilutive: As of June 30, 2015 2014 Stock options to purchase common stock 4,620 6,482 Restricted stock units 3,160 2,236 Employee stock purchase plan 78 106 Common stock subject to repurchase 54 — Bonus and other liability awards 158 — 1.25% Convertible senior notes 5,158 5,158 0.75% Convertible senior notes 2,831 — Total 16,059 13,982

Segment Reporting (Tables)

Segment Reporting (Tables)	6 Months Ended
	Jun. 30, 2015
Segment Reporting [Abstract]
Revenue from external customers by products and services [Table Text Block]	The following set forth total revenue by solutions offered by the Company and geographic area. Revenue by geographic area is based upon the billing address of the customer: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Total revenue by solution: Privacy, Protection and Security $ 50,431 $ 35,549 $ 95,802 $ 68,152 Archiving and Governance 13,115 10,849 25,507 20,950 Total revenue $ 63,546 $ 46,398 $ 121,309 $ 89,102
Total revenue and long-lived assets by geographic area [Table Text Block]	Three Months Ended June 30, Six Months Ended 2015 2014 2015 2014 Total revenue: United States $ 52,701 $ 38,012 $ 99,755 $ 73,229 Rest of world 10,845 8,386 21,554 15,873 Total revenue $ 63,546 $ 46,398 $ 121,309 $ 89,102 Long-lived assets by geographic area are presented below: As of June 30, As of December 31, 2015 2014 Long-lived assets: United States $ 23,314 $ 15,974 Rest of world 3,460 2,744 Total long‑lived assets $ 26,774 $ 18,718

The Company and Summary of Si31

The Company and Summary of Significant Accounting Policies - Goodwill and Intangible Assets (Details) - 6 months ended Jun. 30, 2015 - USD ($) $ in Thousands	Total
Intangible assets:
Goodwill, impairment loss	$ 0
Minimum [Member] | Patents [Member]
Intangible assets:
Estimated life of intangible assets	4 years
Minimum [Member] | Developed technology rights [Member]
Intangible assets:
Estimated life of intangible assets	3 years
Minimum [Member] | Customer relationships [Member]
Intangible assets:
Estimated life of intangible assets	2 years
Minimum [Member] | Noncompete agreements [Member]
Intangible assets:
Estimated life of intangible assets	2 years
Minimum [Member] | Order or Production Backlog [Member]
Intangible assets:
Estimated life of intangible assets	1 year
Minimum [Member] | Trademarks and Trade Names [Member]
Intangible assets:
Estimated life of intangible assets	1 year
Maximum [Member] | Patents [Member]
Intangible assets:
Estimated life of intangible assets	5 years
Maximum [Member] | Developed technology rights [Member]
Intangible assets:
Estimated life of intangible assets	7 years
Maximum [Member] | Customer relationships [Member]
Intangible assets:
Estimated life of intangible assets	7 years
Maximum [Member] | Noncompete agreements [Member]
Intangible assets:
Estimated life of intangible assets	4 years
Maximum [Member] | Order or Production Backlog [Member]
Intangible assets:
Estimated life of intangible assets	2 years
Maximum [Member] | Trademarks and Trade Names [Member]
Intangible assets:
Estimated life of intangible assets	5 years

The Company and Summary of Si32

The Company and Summary of Significant Accounting Policies The Company and Summary of Significant Accounting Policies - Recent Accounting Policies (Details) $ in Thousands	Dec. 31, 2014USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt Issuance Cost	$ 234

The Company and Summary of Si33

The Company and Summary of Significant Accounting Policies The Company and Summary of Significant Accounting Policies - Basis of Presentation and Consolidation (Details)	6 Months Ended	12 Months Ended	18 Months Ended
	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2015business
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Number of Businesses Acquired	1	2	3
Business Combination Disclosure [Text Block]	Acquisitions Acquisitions are accounted for under the purchase method of accounting in which the tangible and identifiable intangible assets and liabilities of each acquired company are recorded at their respective fair values as of each acquisition date, including an amount for goodwill representing the difference between the respective acquisition consideration and fair values of identifiable net assets. The Company believes that for each acquisition, the combined entities will achieve savings in corporate overhead costs and opportunities for growth through expanded geographic and customer segment diversity with the ability to leverage additional products and capabilities. These factors, among others, contributed to a purchase price in excess of the estimated fair value of each acquired company's net identifiable assets acquired and, as a result, goodwill was recorded in connection with each acquisition. Goodwill related to each acquisition below, other than Emerging Threats Pro, LLC, is not deductible for tax purposes. While the Company uses its best estimates and assumptions as part of the purchase price allocation process to value assets acquired and liabilities assumed at the acquisition date, these estimates and assumptions are subject to refinement. When additional information becomes available, such as finalization of negotiations of working capital adjustments and tax related matters, the Company may revise its preliminary purchase price allocation. As a result, during the preliminary purchase price allocation period, which may be up to one year from the acquisition date, the Company may record adjustments to the assets acquired and liabilities assumed, with the corresponding offset to goodwill. Subsequent to the purchase price allocation period, adjustments to assets acquired or liabilities assumed are recognized in the operating results. During the six months period ended June 30, 2015 and for the year ended December 31, 2014, the Company acquired a total of 3 companies (collectively, the "Acquisitions") which are further described below. Emerging Threats Pro, LLC On March 6, 2015 (the "Emerging Threats Acquisition Date"), pursuant to the terms of a Purchase Agreement, the Company acquired 100% of membership interests in Emerging Threats Pro, LLC ("Emerging Threats"). Based in Indianapolis, Indiana, Emerging Threats provides threat intelligence solutions to help protect networks from known or potentially malicious threats. With this acquisition, the Company intends to integrate Emerging Threat's advanced threat intelligence solutions with its existing Targeted Attack Protection and Threat Response security solutions to advance threat detection and response across the completed attack chain. The combined technology will provide customers with deeper insight into cyberthreats, enabling them to react faster to inbound cyberattacks, and to identify, block, and disable previously undetected malware already embedded in their organizations. The Company has provisionally estimated the fair values for the acquired tangible and identifiable intangible assets and liabilities assumed at the Emerging Threats Acquisition Date. The amounts reported were considered provisional as the Company was completing the valuation work to determine the fair value of certain assets acquired and liabilities assumed. The results of operations and the provisional fair values of the acquired assets and liabilities assumed have been included in the accompanying condensed consolidated financial statements since the Emerging Threat Acquisition Date. Revenue from Emerging Threats was not material for the three and six months ended June 30, 2015, and due to the continued integration of the combined businesses, it was impractical to determine the earnings. The total purchase price was $31,803 , net of cash acquired of $52 , of which $3,662 was paid in the second quarter of 2015. Of the cash consideration paid, $6,000 was held in escrow, to secure indemnification obligations, which has not been released as of the filing date of this Quarterly Report on Form 10-Q. The Company incurred $275 in acquisition-related costs which were recorded within operating expenses for the six months ended June 30, 2015. Fair value of acquired assets and liabilities assumed The determination of the fair values of the assets acquired and liabilities assumed has been prepared on a provisional basis and changes to that determination may occur as additional information becomes available. The following table summarizes the fair values of tangible and intangible assets acquired, liabilities assumed and goodwill: Estimated Estimated Current assets acquired $ 1,284 N/A Fixed assets acquired 174 N/A Liabilities assumed (448 ) N/A Deferred revenue assumed (700 ) N/A Holdback liability to the sellers (3,662 ) N/A Trade names 200 2 Customer relationships 4,200 7 Order Backlog 200 1 Developed technology 7,900 7 Goodwill 19,045 Indefinite $ 28,193 Nexgate, Inc. On October 31, 2014 (the "Nexgate Acquisition Date"), pursuant to the terms of an Agreement and Plan of Merger, a wholly-owned subsidiary of the Company merged with and into Nexgate, Inc. ("Nexgate"), with Nexgate surviving as a wholly-owned subsidiary of the Company. Formerly based in Burlingame, California, Nexgate provides cloud-based brand protection and compliance for enterprise social media accounts. With this acquisition, the Company's customers can effectively protect their online brand presence and social media communication infrastructure. Nexgate technology identifies and remediates fraudulent social media accounts, account hacks, and content that contains malware, spam and abusive language. In addition, the Nexgate solution enforces policy on authorized accounts and posts for compliance with a wide-range of social media regulatory requirements. The Company has provisionally estimated the fair values for the acquired tangible and identifiable intangible assets and liabilities assumed at the Nexgate Acquisition Date. The amounts reported were considered provisional as the Company was completing the valuation work to determine the fair value of certain assets acquired and liabilities assumed. The results of operations and the provisional fair values of the acquired assets and liabilities assumed have been included in the accompanying consolidated financial statements since the Nexgate Acquisition Date. At the Nexgate Acquisition Date, the Company paid $31,771 in cash consideration, net of cash acquired of $1,032 . Of the cash consideration paid, $5,250 was held in escrow to secure indemnification obligations, which has not been released as of the filing date of this Quarterly Report on Form 10-Q. Fair value of acquired assets and liabilities assumed The determination of the fair values of the assets acquired and liabilities assumed has been prepared on a provisional basis and changes to that determination may occur as additional information becomes available. The following table summarizes the fair values of tangible assets acquired, liabilities assumed, intangible assets and goodwill: Estimated Estimated Current assets acquired $ 1,340 N/A Fixed assets acquired 15 N/A Liabilities assumed (64 ) N/A Deferred revenue assumed (600 ) N/A Customer relationships 3,000 7 Order backlog 200 2 Developed technology 3,200 4 In-process research and development 900 N/A Deferred tax liability, net (792 ) N/A Goodwill 25,604 Indefinite $ 32,803 NetCitadel, Inc. On May 13, 2014 (the "NetCitadel Acquisition Date"), pursuant to the terms of an Agreement and Plan of Merger, a wholly-owned subsidiary of the Company merged with and into NetCitadel, Inc. ("NetCitadel"), with NetCitadel surviving as a wholly-owned subsidiary of the Company. Formerly based in Mountain View, California, NetCitadel is a pioneer in the field of automated security incident response. The acquisition extends the reach and capabilities of the Company's existing advanced threat solutions, adding additional threat verification and containment capabilities via an open platform that unifies products from the Company and other vendors. The results of operations and the fair values of the acquired assets and liabilities assumed have been included in the accompanying consolidated financial statements since the NetCitadel Acquisition Date. At the NetCitadel Acquisition Date, the Company paid $22,731 . Of the cash consideration paid, $3,369 was held in escrow to secure indemnification obligations, which has not been released as of the filing date of this Form 10-Q. Fair value of acquired assets and liabilities assumed The following table summarizes the fair values of tangible assets acquired, liabilities assumed, intangible assets and goodwill: Fair Value Estimated Tangible assets acquired $ 14 N/A Liabilities assumed (1,267 ) N/A Customer relationships 100 5 Developed technology 5,500 5 Goodwill 18,384 Indefinite $ 22,731 Pro Forma Financial Information The following unaudited pro forma financial information presents the combined results of operations for the three and six months ended June 30, 2015 and 2014 of the Company, Emerging Threats, assuming that Emerging Threats was acquired as of January 1, 2014, and NetCitadel, assuming that NetCitadel was acquired as of January 1, 2013. Adjustments were made to give effect to pro forma events that are directly attributable to the acquisitions such as amortization expense of acquired intangible assets, stock-based compensation directly attributable to the acquisition and acquisition-related transaction costs. The unaudited pro forma results do not reflect any operating efficiencies or potential cost savings which may result from the consolidation of the operations of the Company and acquired businesses. Accordingly, these unaudited pro forma results are presented for informational purposes only and are not necessarily indicative of what the actual results of operations of the combined company would have been if the acquisitions had occurred at the beginning of the period presented, nor are they indicative of future results of operations: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Total revenue $ 63,335 $ 47,274 $ 121,104 $ 90,719 Net loss (24,923 ) (16,304 ) (48,116 ) (32,150 ) Basic and diluted net loss per share $ (0.63 ) $ (0.44 ) $ (1.23 ) $ (0.87 ) The unaudited pro forma financial information includes non-recurring acquisition-related transaction costs of $275 for the six months ended June 30, 2014 .

Acquisitions (Details)

Acquisitions (Details) - Subsequent Event Type [Domain] $ in Thousands	Mar. 06, 2015USD ($)	Oct. 31, 2014USD ($)	May. 13, 2014USD ($)	Jun. 30, 2015USD ($)	Jun. 30, 2014USD ($)	Dec. 31, 2014USD ($)	Jun. 30, 2015USD ($)business
Business Acquisition [Line Items]
Number of Businesses Acquired				1		2	3
Payments to acquire businesses, net of cash acquired				$ 31,624	$ 22,754
Acquisition-related costs					$ 275
Goodwill				126,525		$ 107,504	$ 126,525
Emerging Threats [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets	$ 1,284
Business Acquisition, Percentage of Voting Interests Acquired	100.00%
Business Combination, Consideration Transferred	$ 31,803
Cash Acquired from Acquisition	52
Business Combination, Consideration Transferred, Liabilities Incurred	(3,662)
Contingent consideration arrangements, range of outcomes, value, high	6,000
Acquisition-related costs				$ 275
Goodwill	19,045
Recognized identifiable assets acquired and liabilities assumed, net	28,193
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	174
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities, Current and Noncurrent Liabilities, Not Otherwise Defined	(448)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue	(700)
Nexgate [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets		$ 1,340
Payments to acquire businesses, net of cash acquired		31,771
Cash Acquired from Acquisition		1,032
Contingent consideration arrangements, range of outcomes, value, high		5,250
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities, Net		792
Goodwill		25,604
Recognized identifiable assets acquired and liabilities assumed, net		32,803
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		15
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities, Current and Noncurrent Liabilities, Not Otherwise Defined		(64)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Deferred Revenue		600
NetCitadel [Member]
Business Acquisition [Line Items]
Contingent consideration arrangements, range of outcomes, value, high			$ 3,369
Payments to Acquire Businesses, Gross			22,731
Goodwill			18,384
Recognized identifiable assets acquired and liabilities assumed, net			22,731
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment			14
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities, Current and Noncurrent Liabilities, Not Otherwise Defined			(1,267)
Trademarks and Trade Names [Member] | Emerging Threats [Member]
Business Acquisition [Line Items]
Recognized identifiable assets acquired and liabilities assumed, finite-lived intangibles	$ 200
Acquired finite-lived intangible assets, weighted average useful life	2 years
Customer relationships [Member] | Emerging Threats [Member]
Business Acquisition [Line Items]
Recognized identifiable assets acquired and liabilities assumed, finite-lived intangibles	$ 4,200
Acquired finite-lived intangible assets, weighted average useful life	7 years
Customer relationships [Member] | Nexgate [Member]
Business Acquisition [Line Items]
Recognized identifiable assets acquired and liabilities assumed, finite-lived intangibles		$ 3,000
Acquired finite-lived intangible assets, weighted average useful life		7 years
Customer relationships [Member] | NetCitadel [Member]
Business Acquisition [Line Items]
Recognized identifiable assets acquired and liabilities assumed, finite-lived intangibles			$ 100
Acquired finite-lived intangible assets, weighted average useful life			5 years
Order or Production Backlog [Member] | Emerging Threats [Member]
Business Acquisition [Line Items]
Recognized identifiable assets acquired and liabilities assumed, finite-lived intangibles	$ 200
Acquired finite-lived intangible assets, weighted average useful life	1 year
Order or Production Backlog [Member] | Nexgate [Member]
Business Acquisition [Line Items]
Recognized identifiable assets acquired and liabilities assumed, finite-lived intangibles		$ 200
Acquired finite-lived intangible assets, weighted average useful life		2 years
Developed technology rights [Member] | Emerging Threats [Member]
Business Acquisition [Line Items]
Recognized identifiable assets acquired and liabilities assumed, finite-lived intangibles	$ 7,900
Acquired finite-lived intangible assets, weighted average useful life	7 years
Developed technology rights [Member] | Nexgate [Member]
Business Acquisition [Line Items]
Recognized identifiable assets acquired and liabilities assumed, finite-lived intangibles		$ 3,200
Acquired finite-lived intangible assets, weighted average useful life		4 years
Developed technology rights [Member] | NetCitadel [Member]
Business Acquisition [Line Items]
Recognized identifiable assets acquired and liabilities assumed, finite-lived intangibles			$ 5,500
Acquired finite-lived intangible assets, weighted average useful life			5 years
In Process Research and Development [Member] | Nexgate [Member]
Business Acquisition [Line Items]
Recognized identifiable assets acquired and liabilities assumed, finite-lived intangibles		$ 900

Acquisitions - Pro Forma Financ

Acquisitions - Pro Forma Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Total revenue	$ 63,335	$ 47,274	$ 121,104	$ 90,719
Net loss	$ (24,923)	$ (16,304)	$ (48,116)	$ (32,150)
Basic and diluted net loss per share (in dollars per share)	$ (0.63)	$ (0.44)	$ (1.23)	$ (0.87)
Acquisition-related costs				$ 275

Goodwill and Intangible Asset36

Goodwill and Intangible Assets - Goodwill (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2015USD ($)
Goodwill activity and balances
Opening balance	$ 107,504
Add: Goodwill from acquisitions	19,395
Less: Other adjustments to goodwill	(374)
Closing balance	$ 126,525

Goodwill and Intangible Asset37

Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Intangible assets excluding goodwill:
Finite-lived intangible assets, gross carrying amount	$ 69,760		$ 69,760		$ 57,260
Finite-lived intangible assets, accumulated amortization	(35,798)		(35,798)		(30,174)
Finite-lived intangible assets, net carrying amount	33,962		33,962		27,086
Intangible amortization expense	2,917	$ 2,109	5,624	$ 4,069
Future estimated amortization costs of intangible assets:
2015, remainder	5,637		5,637
2,016	9,288		9,288
2,017	5,944		5,944
2,018	5,348		5,348
2,019	3,095		3,095
Thereafter	4,650		4,650
Finite-lived intangible assets, net carrying amount	33,962		33,962		27,086
Developed technology rights [Member]
Intangible assets excluding goodwill:
Finite-lived intangible assets, gross carrying amount	46,068		46,068		38,168
Finite-lived intangible assets, accumulated amortization	(24,508)		(24,508)		(21,538)
Finite-lived intangible assets, net carrying amount	21,560		21,560		16,630
Future estimated amortization costs of intangible assets:
Finite-lived intangible assets, net carrying amount	21,560		21,560		16,630
Customer relationships [Member]
Intangible assets excluding goodwill:
Finite-lived intangible assets, gross carrying amount	20,582		20,582		16,382
Finite-lived intangible assets, accumulated amortization	(10,192)		(10,192)		(7,893)
Finite-lived intangible assets, net carrying amount	10,390		10,390		8,489
Future estimated amortization costs of intangible assets:
Finite-lived intangible assets, net carrying amount	10,390		10,390		8,489
Noncompete agreements [Member]
Intangible assets excluding goodwill:
Finite-lived intangible assets, gross carrying amount	804		804		804
Finite-lived intangible assets, accumulated amortization	(594)		(594)		(462)
Finite-lived intangible assets, net carrying amount	210		210		342
Future estimated amortization costs of intangible assets:
Finite-lived intangible assets, net carrying amount	210		210		342
Trademarks and patents [Member]
Intangible assets excluding goodwill:
Finite-lived intangible assets, gross carrying amount	1,006		1,006		806
Finite-lived intangible assets, accumulated amortization	(374)		(374)		(264)
Finite-lived intangible assets, net carrying amount	632		632		542
Future estimated amortization costs of intangible assets:
Finite-lived intangible assets, net carrying amount	632		632		542
Order or Production Backlog [Member]
Intangible assets excluding goodwill:
Finite-lived intangible assets, gross carrying amount	400		400		200
Finite-lived intangible assets, accumulated amortization	(130)		(130)		(17)
Finite-lived intangible assets, net carrying amount	270		270		183
Future estimated amortization costs of intangible assets:
Finite-lived intangible assets, net carrying amount	270		270		183
In Process Research and Development [Member]
Intangible assets excluding goodwill:
Finite-lived intangible assets, gross carrying amount	900		900		900
Finite-lived intangible assets, accumulated amortization	0		0		0
Finite-lived intangible assets, net carrying amount	900		900		900
Future estimated amortization costs of intangible assets:
Finite-lived intangible assets, net carrying amount	$ 900		$ 900		$ 900

Fair Value Measurements and I38

Fair Value Measurements and Investments - Fair Value Measurements (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Fair value measurements and investments
Cash and cash equivalents	$ 402,144	$ 180,337	$ 226,845	$ 243,786
Cash and cash equivalents, fair value disclosures	402,144	180,337
Short-term investments, amortized cost basis	8,512	34,676
Short-term investments, fair value disclosures	8,510	34,649
Estimate of fair value (balance) [Member]
Fair value measurements and investments
Assets, Fair Value Disclosure	395,382	174,293
Quoted prices in active markets for identical assets (Level 1) [Member]
Fair value measurements and investments
Assets, Fair Value Disclosure	386,872	139,644
Fair Value, Inputs, Level 2 [Member]
Fair value measurements and investments
Assets, Fair Value Disclosure	8,510	34,649
Convertible Senior Notes 1 Point 25 Percent [Member]
Fair value measurements and investments
Convertible debt, fair value disclosures	248,812
Convertible Senior Notes 0 Point 75 [Member]
Fair value measurements and investments
Convertible debt, fair value disclosures	340,694
Cash [Member]
Fair value measurements and investments
Cash and cash equivalents	15,272	40,693
Cash and cash equivalents, fair value disclosures	15,272	40,693
Money market funds [Member]
Fair value measurements and investments
Cash and cash equivalents	386,872	139,644
Cash and cash equivalents, fair value disclosures	386,872	139,644
Money market funds [Member] | Estimate of fair value (balance) [Member]
Fair value measurements and investments
Cash and cash equivalents, fair value disclosures	386,872	139,644
Money market funds [Member] | Quoted prices in active markets for identical assets (Level 1) [Member]
Fair value measurements and investments
Cash and cash equivalents, fair value disclosures	386,872	139,644
Corporate debt securities [Member]
Fair value measurements and investments
Short-term investments, amortized cost basis	8,512	31,678
Short-term investments, fair value disclosures	8,510	31,651
Corporate debt securities [Member] | Estimate of fair value (balance) [Member]
Fair value measurements and investments
Short-term investments, fair value disclosures	8,510	31,651
Corporate debt securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value measurements and investments
Short-term investments, fair value disclosures	$ 8,510	31,651
Commercial paper [Member] | Estimate of fair value (balance) [Member]
Fair value measurements and investments
Short-term investments, fair value disclosures		2,998
Commercial paper [Member] | Fair Value, Inputs, Level 2 [Member]
Fair value measurements and investments
Short-term investments, fair value disclosures		$ 2,998

Fair Value Measurements and I39

Fair Value Measurements and Investments Fair Value Measurements and Investments - Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Schedule of cash and cash equivalents, and investments
Cash and cash equivalents, fair value disclosures	$ 402,144	$ 180,337
Cash and cash equivalents	402,144	180,337	$ 226,845	$ 243,786
Short-term investments, amortized cost basis	8,512	34,676
Short-term investments, fair value disclosures	8,510	34,649
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	0
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	2	27
Cash [Member]
Schedule of cash and cash equivalents, and investments
Cash and cash equivalents, fair value disclosures	15,272	40,693
Cash and cash equivalents	15,272	40,693
Money market funds [Member]
Schedule of cash and cash equivalents, and investments
Cash and cash equivalents, fair value disclosures	386,872	139,644
Cash and cash equivalents	386,872	139,644
Corporate debt securities [Member]
Schedule of cash and cash equivalents, and investments
Short-term investments, amortized cost basis	8,512	31,678
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	2	27
Short-term investments, fair value disclosures	8,510	31,651
Certificates of Deposit [Member]
Schedule of cash and cash equivalents, and investments
Short-term investments, amortized cost basis		2,998
Short-term investments, fair value disclosures		2,998
Fair Value, Inputs, Level 2 [Member]
Fair value measurements and investments
Assets, Fair Value Disclosure	8,510	34,649
Fair Value, Inputs, Level 2 [Member] | Corporate debt securities [Member]
Schedule of cash and cash equivalents, and investments
Short-term investments, fair value disclosures	$ 8,510	31,651
Fair Value, Inputs, Level 2 [Member] | Commercial paper [Member]
Schedule of cash and cash equivalents, and investments
Short-term investments, fair value disclosures		$ 2,998

Commitments and Contingencies40

Commitments and Contingencies (Details) - USD ($) $ in Thousands	Apr. 15, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Jul. 31, 2012
Commitments and Contingencies Disclosure [Abstract]
Operating lease rent expense		$ 951	$ 860	$ 1,818	$ 1,398
Future annual minimum lease payments under noncancelable operating and capital leases
2015, remainder		2		2
2,016		0		0
2,017		0		0
2,018		0		0
2,019		0		0
Thereafter		0		0
Total minimum capital lease payments		2		2
Less: Amount representing interest		0		0
Present value of capital lease obligations		2		2
Less: Current portion		(2)		(2)
Long-term portion of capital lease obligations		0		0
Operating lease obligations
2015, remainder		4,032		4,032
2,016		7,343		7,343
2,017		3,915		3,915
2,018		3,816		3,816
2,019		3,643		3,643
Thereafter		1,291		1,291
Total minimum operating lease payments		$ 24,040		$ 24,040
Damages sought, value	$ 13,500
Capital Lease Obligations [Member]
Debt instrument
Interest rate, stated percentage						4.50%

Convertible Senior Notes (Detai

Convertible Senior Notes (Details) $ / shares in Units, shares in Thousands	Jun. 17, 2015USD ($)shares$ / shares	Dec. 11, 2013USD ($)shares$ / shares	Jun. 30, 2015USD ($)	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)	Jun. 30, 2014USD ($)	Dec. 31, 2014USD ($)
Debt instrument
Proceeds from convertible debt					$ 223,790,000	$ 0
Convertible senior notes			$ 335,728,000		335,728,000		$ 161,396,000
Amortization of debt issuance costs and accretion of debt discount					4,962,000	4,316,000
Convertible debt [Member]
Debt instrument
Convertible senior notes			335,728,000		335,728,000
Convertible Senior Notes 0 Point 75 [Member]
Debt instrument
Debt Instrument Face Amount Initial	$ 200,000,000
Face amount optional	$ 30,000,000
Debt issuance cost					6,581,000
Proceeds from convertible debt					223,419,000
Interest rate, stated percentage	0.75%
Conversion ratio, initial (in shares)	12.3108
Number of shares convertible, initial rate (in shares) | shares	2,831
Conversion price per share, initial (USD per share) | $ / shares	$ 81.23
Effective rate used to amortize debt discount	6.50%
Convertible senior notes	$ 174,359,000		169,769,000		169,769,000
Carrying amount of equity component	55,641,000
Debt discount, net of amortization			(60,231,000)		(60,231,000)
Carrying amount of the equity component net			54,049,000		54,049,000
Issuance costs allocated to equity portion	$ 1,592,000
Debt Instrument, Face Amount			230,000,000		230,000,000
Convertible Senior Notes 1 Point 25 Percent [Member]
Debt instrument
Debt Instrument Face Amount Initial		$ 175,000,000
Face amount optional		26,250,000
Debt issuance cost		5,803,000
Proceeds from convertible debt		$ 195,446,000
Interest rate, stated percentage		1.25%
Conversion ratio, initial (in shares)		25.6271
Number of shares convertible, initial rate (in shares) | shares		5,158
Conversion price per share, initial (USD per share) | $ / shares		$ 39.02
Threshold percentage of stock price trigger	130.00%
Threshold trading days	20
Threshold consecutive trading days	30 days
Number of consecutive business days following consecutive trading day period	5 days
Debt Instrument Convertible Period Of Consecutive Trading Days	5 days
Trading price as percentage of closing price of common stock	98.00%
Effective rate used to amortize debt discount		6.50%
Convertible senior notes		$ 156,672,000	165,959,000		165,959,000
Carrying amount of equity component		44,578,000
Debt discount, net of amortization			(35,291,000)		(35,291,000)
Carrying amount of the equity component net			43,293,000		43,293,000
Issuance costs allocated to equity portion		$ 1,285,000
Debt Instrument, Face Amount			201,250,000		201,250,000
Convertible debt [Member]
Debt instrument
Debt discount, net of amortization			(95,522,000)		(95,522,000)
Carrying amount of the equity component net			97,342,000		97,342,000
Issuance costs allocated to equity portion			2,877,000		2,877,000
Interest expense, 1.25% coupon			691,000	$ 624,000	1,320,000	1,253,000
Amortization of debt issuance costs and accretion of debt discount			2,696,000	2,173,000	4,962,000	4,316,000
Interest expense, total			3,387,000	$ 2,797,000	6,282,000	$ 5,569,000
Debt Instrument, Face Amount			$ 431,250,000		$ 431,250,000

Debt (Details)

Debt (Details) - USD ($) $ in Thousands	Apr. 30, 2011	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 17, 2015
Convertible Senior Notes 0 Point 75 [Member]
Debt instrument
Debt Instrument Face Amount Initial						$ 200,000
Interest rate at period end						6.50%
Loans Payable [Member]
Debt instrument
Long-term Debt	$ 6,000
Duration until repayment date after a loan amount is drawn	48 months
Interest expense		$ 1	$ 23	$ 5	$ 51
Prime Rate [Member] | Loans Payable [Member]
Debt instrument
Basis spread on variable rate	0.50%

Common Stock (Details)

Common Stock (Details)	Jun. 30, 2015class$ / sharesshares	Dec. 31, 2014$ / sharesshares
Stockholders' equity:
Number of classes of stock the Company is authorized to issue (in classes of stock) | class	2
Total shares authorized (in shares)	205,000,000
Preferred stock authorized (in shares)	5,000,000	5,000,000
Common Stock, Shares Authorized	200,000,000	200,000,000
Par value of common stock (USD per share) | $ / shares	$ 0.0001	$ 0.0001
Preferred Stock, Par or Stated Value Per Share | $ / shares	$ 0.0001	$ 0.0001
Number of shares of common stock reserved for future issuance
Total shares reserved	22,555,000	18,636,000
Employee stock option [Member]
Number of shares of common stock reserved for future issuance
Shares available for future grant under the stock plans (in shares)	5,560,000	4,330,000
Convertible debt [Member]
Number of shares of common stock reserved for future issuance
Common stock issuable upon conversion of convertible senior notes (in shares)	7,989,000	5,158,000
ESPP 2012 Plan [Member]
Number of shares of common stock reserved for future issuance
Increase in Common Stock Reserved and Available for Issuance ESPP	1,226,000	926,000
2012 Equity Incentive Plan [Member] | Restricted stock units (RSUs) [Member]
Number of shares of common stock reserved for future issuance
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	3,160,000	2,934,000

Stock Equity Plans - Stock-Base

Stock Equity Plans - Stock-Based Compensation Plans (Details) shares in Thousands	6 Months Ended
	Jun. 30, 2015planshares	Dec. 31, 2014shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity incentive plans held by the company (number of plans) | plan	2
Employee stock option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grant under the stock plans (in shares)	5,560	4,330
2012 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance (in shares)	20,316
Annual percentage increase in number of shares authorized	5.00%
Maximum number of additional shares to be authorized (in shares)	3,724
2012 Equity Incentive Plan [Member] | Employee stock option [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
2012 Equity Incentive Plan [Member] | Employee stock option [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term until award expiration	10 years
Award vesting period	4 years
2012 Equity Incentive Plan [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years

Stock Equity Plans - Stock Opti

Stock Equity Plans - Stock Option Activity (Details) - Employee stock option [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grant under the stock plans (in shares)	5,560		5,560		4,330
Stock option activity under the Plan
Outstanding, beginning of period (in shares)			5,288
Outstanding, ending of period (in shares)					5,288
2012 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value per share	$ 28.23	$ 19.51	$ 27.81	$ 19.88
Fair value assumptions
Expected dividend rate	0.00%	0.00%	0.00%	0.00%
Stock option activity under the Plan
Outstanding, beginning of period (in shares)			5,288
Options granted (in shares)			259
Options exercised (in shares)			(843)
Options forfeited and expired (in shares)			(84)
Outstanding, ending of period (in shares)	4,620		4,620		5,288
Stock option activity under the Plan, in weighted average exercise price:
Balance at beginning of period (USD per share)			$ 11.06
Options granted (USD per share)			56.68
Options exercised (USD per share)			7.73
Options forfeited and expired (USD per share)			19.36
Balance at ending of period (USD per share)	$ 14.08		$ 14.08		$ 11.06
Weighted average remaining contractual term			6 years 1 month 11 days		6 years 3 months 22 days
Aggregate intrinsic value, outstanding	$ 229,116		$ 229,116		$ 196,608
Aggregate intrinsic value, exercised			40,237	$ 32,192
Proceeds from stock options exercised			6,520	6,465
Fair value of options, vested in period			5,896	$ 5,870
Unamortized stock-based compensation expense	$ 16,654		$ 16,654
Average remaining vesting term			2 years 1 month 19 days
Maximum [Member] | 2012 Equity Incentive Plan [Member]
Fair value assumptions
Expected life	6 years 29 days	6 years 29 days	6 years 29 days	6 years 29 days
Weighted average volatility rate		58.00%	52.00%	58.00%
Risk free interest rate		1.90%	1.70%	1.90%
Minimum [Member] | 2012 Equity Incentive Plan [Member]
Fair value assumptions
Expected life	5 years 112 days	5 years 112 days	5 years 112 days	5 years 112 days
Weighted average volatility rate	50.00%	54.00%	50.00%	54.00%
Risk free interest rate	1.70%	1.80%	1.60%	1.80%

Stock Equity Plans - Restricted

Stock Equity Plans - Restricted Stock Units (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2015	Jun. 30, 2014
RSUs outstanding, granted fair value per unit
Fair value of shares granted		$ 2,357
Stock-based Compensation Expense			$ 729
ESPP 2012 Plan [Member]
RSUs outstanding, granted fair value per unit
Unamortized stock-based compensation expense	$ 882		$ 882
Average remaining vesting term	3 years 3 months 8 days		4 months 17 days
Restricted Stock [Member]
RSU's outstanding, number of shares:
Restricted Stock granted (in shares)		54
RSUs outstanding, granted fair value per unit
Unamortized stock-based compensation expense	$ 1,572		$ 1,572
Stock-based Compensation Expense			$ 589
Restricted stock units (RSUs) [Member] | 2012 Equity Incentive Plan [Member]
RSU's outstanding, number of shares:
Awarded at beginning of period (in shares)			2,934
Restricted Stock granted (in shares)			801
Awards vested (in shares)			(459)
Awards forfeited (in shares)			(116)
Awarded at end of period (in shares)	3,160	2,934	3,160
RSUs outstanding, granted fair value per unit
Awarded at beginning of period (USD per share)			$ 37.45
Awards granted (USD per share)			57.37
Awards vested (USD per share)			35.64
Awards forfeited (USD per share)			34.82
Awarded at end of period (USD per share)	$ 42.87	$ 37.45	$ 42.87
Unamortized stock-based compensation expense	$ 82,846		$ 82,846
Performance Shares [Member] | 2012 Equity Incentive Plan [Member]
RSUs outstanding, granted fair value per unit
Unamortized stock-based compensation expense	$ 4,046		$ 4,046
Performance restricted stock units, Granted in Period			172	17
Stock Bonus Awards [Member] | 2012 Equity Incentive Plan [Member]
RSUs outstanding, granted fair value per unit
Stock-based Compensation Expense			$ 1,459	$ 988

Stock Equity Plans - Employee S

Stock Equity Plans - Employee Stock Purchase Plan (Details) - Range [Domain] - ESPP 2012 Plan [Member] - USD ($) shares in Thousands, $ in Thousands	Mar. 30, 2012	Jun. 30, 2015	Jun. 30, 2015	Dec. 31, 2014
Employee stock purchase plan
Number of shares authorized ESPP (in shares)	745
Annual percentage increase of maximum number of shares reserved for issuance ESPP	1.00%
Maximum number of shares to be available for grant ESPP (in shares)	1,490
Increase in Common Stock Reserved and Available for Issuance ESPP		1,226	1,226	926
Unamortized stock-based compensation expense		$ 882	$ 882
Average remaining vesting term		3 years 3 months 8 days	4 months 17 days

Stock Equity Plans Performance

Stock Equity Plans Performance Stock Units (Details) - 2012 Equity Incentive Plan [Member] - Performance Shares [Member] - USD ($) shares in Thousands, $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance restricted stock units, Granted in Period	172	17
Unamortized stock-based compensation expense	$ 4,046

Stock Equity Plans Stock Bonus

Stock Equity Plans Stock Bonus and Other Liability Awards (Details) - USD ($) shares in Thousands, $ in Thousands	Mar. 06, 2015	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based Compensation Expense		$ 729
Fair Value of Liability Award Issued	$ 6,885
2012 Equity Incentive Plan [Member] | Stock Bonus Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accrued stock bonuses, Current		$ 1,459		$ 1,771
Stock bonus awards, Shares Issued in Period		27	22
Stock-based Compensation Expense		$ 1,459	$ 988

Net Loss per Share (Details)

Net Loss per Share (Details) - shares shares in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Antidilutive securities excluded from computation of earnings per share
Total antidilutive securities excluded from computation of earnings per share (in shares)	16,059	13,982
Employee stock option [Member]
Antidilutive securities excluded from computation of earnings per share
Total antidilutive securities excluded from computation of earnings per share (in shares)	4,620	6,482
Employee stock purchase plan [Member]
Antidilutive securities excluded from computation of earnings per share
Total antidilutive securities excluded from computation of earnings per share (in shares)	78	106
Common stock subject to repurchase [Member]
Antidilutive securities excluded from computation of earnings per share
Total antidilutive securities excluded from computation of earnings per share (in shares)	54	0
Stock Bonus Awards [Member]
Antidilutive securities excluded from computation of earnings per share
Total antidilutive securities excluded from computation of earnings per share (in shares)	158	0
Convertible Senior Notes 1 Point 25 Percent [Member]
Antidilutive securities excluded from computation of earnings per share
Total antidilutive securities excluded from computation of earnings per share (in shares)	5,158
Restricted stock units (RSUs) [Member]
Antidilutive securities excluded from computation of earnings per share
Total antidilutive securities excluded from computation of earnings per share (in shares)	3,160	2,236
Convertible debt [Member]
Antidilutive securities excluded from computation of earnings per share
Total antidilutive securities excluded from computation of earnings per share (in shares)		5,158
Convertible Senior Notes 0 Point 75 [Member]
Antidilutive securities excluded from computation of earnings per share
Total antidilutive securities excluded from computation of earnings per share (in shares)	2,831

Segment Reporting - Revenue by

Segment Reporting - Revenue by Solution (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015USD ($)	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)segment	Jun. 30, 2014USD ($)
Revenue by Solution [Abstract]
Number of operating and reportable segments | segment			1
Revenue from external customers
Revenue	$ 63,546	$ 46,398	$ 121,309	$ 89,102
Privacy, protection and security [Member]
Revenue from external customers
Revenue	50,431	35,549	95,802	68,152
Archiving and governance [Member]
Revenue from external customers
Revenue	$ 13,115	$ 10,849	$ 25,507	$ 20,950

Segment Reporting - by Geograph

Segment Reporting - by Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Segment reporting:
Revenue	$ 63,546	$ 46,398	$ 121,309	$ 89,102
Total long-lived assets	26,774		26,774		$ 18,718
United States [Member]
Segment reporting:
Revenue	52,701	38,012	99,755	73,229
Total long-lived assets	23,314		23,314		15,974
Rest of world [Member]
Segment reporting:
Revenue	10,845	$ 8,386	21,554	$ 15,873
Total long-lived assets	$ 3,460		$ 3,460		$ 2,744

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Valuation allowance
Income tax expense (benefit)	$ 112	$ 147	$ 274	$ 291
Loss before (provision for) benefit from income taxes	24,861	$ 14,978	$ 46,372	$ 29,229
Effective income tax rate			(0.60%)	(1.00%)
Unrecognized tax benefits	4,268		$ 4,268
Accrued interest and penalties	234		234
Uncertain tax benefits that would affect effective tax rate if recognized	$ 1,306		1,306
Increase (decrease) in gross uncertain tax benefits			42
Increase for tax positions taken in the current period			79
Increase (decrease) for tax positions taken in prior periods			18
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations			$ 55

Subsequent Events (Details)

Subsequent Events (Details) $ in Thousands	3 Months Ended
	Sep. 30, 2015USD ($)
Nexgate [Member]
Subsequent Event [Line Items]
Payments to Acquire Businesses, Gross	$ 8,500