Proofpoint (PFPT) 10-Q 7 Aug 14 2014 Q2 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information Document	6 Months Ended
	Jun. 30, 2014	Jul. 31, 2014
Document Information [Line Items]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Jun-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q2	'
Entity Registrant Name	'PROOFPOINT INC.	'
Entity Central Index Key	'0001212458	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	37,410,336

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets	'	'
Cash and cash equivalents	$226,845	$243,786
Short-term investments	0	8,015
Accounts receivable, net of allowance for doubtful accounts of $271 and $276 at June 30, 2014 and December 31, 2013, respectively	26,273	26,221
Inventory	1,343	860
Deferred product costs, current	1,943	1,004
Prepaid expenses and other current assets	10,272	7,963
Total current assets	266,676	287,849
Property and equipment, net	15,337	11,221
Deferred product costs, noncurrent	413	357
Goodwill	82,012	63,764
Intangible assets, net	24,507	22,976
Other noncurrent assets	4,347	4,392
Total assets	393,292	390,559
Current liabilities	'	'
Accounts payable	8,782	7,281
Accrued liabilities	16,892	19,260
Notes payable and lease obligations, current	1,523	1,655
Deferred rent, current	295	297
Deferred revenue, current	98,406	89,450
Total current liabilities	125,898	117,943
Convertible senior notes	157,218	152,928
Notes payable and lease obligations, noncurrent	2	695
Deferred rent, noncurrent	1,180	56
Other long term liabilities	7,095	7,244
Deferred revenue, noncurrent	33,157	34,533
Total liabilities	324,550	313,399
Stockholders’ equity	'	'
Common stock, $0.0001 par value; 200,000 shares authorized at June 30, 2014 and December 31, 2013; 37,299 and 36,140 shares issued and outstanding at June 30, 2014 and December 31, 2013, respectively	4	4
Additional paid-in capital	308,267	287,165
Accumulated deficit	-239,529	-210,009
Total stockholders’ equity	68,742	77,160
Total liabilities and stockholders’ equity	$393,292	$390,559

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets Parenthetical (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, except Per Share data, unless otherwise specified
Allowance for doubtful accounts receivable, current	$271	$276
Number of shares of common stock reserved for future issuance	'	'
Par value of common stock (USD per share)	$0.00	$0.00
Common stock authorized (in shares)	200,000	200,000
Common stock issued (in shares)	37,299	36,140
Common stock outstanding (in shares)	37,299	36,140

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Operations (USD $)	3 Months Ended				6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Revenue:	'		'		'		'
Subscription	$45,047		$30,816		$86,251		$59,268
Hardware and services	1,351		1,011		2,851		3,323
Revenue, net	46,398		31,827		89,102		62,591
Cost of revenue:	'		'		'		'
Subscription	12,544		8,276		23,995		16,105
Hardware and services	2,717		1,203		4,977		2,442
Total cost of revenue	15,261	[1],[2]	9,479	[1],[2]	28,972	[1],[2]	18,547	[1],[2]
Gross profit	31,137		22,348		60,130		44,044
Operating expense:	'		'		'		'
Research and development	12,298		7,591		24,246		15,153
Sales and marketing	24,180		16,239		46,998		32,367
General and administrative	6,846		3,777		12,352		7,679
Total operating expense	43,324	[1],[2]	27,607	[1],[2]	83,596	[1],[2]	55,199	[1],[2]
Operating loss	-12,187		-5,259		-23,466		-11,155
Interest (expense) income, net	-2,798		-5		-5,571		7
Other income (expense), net	7		-148		-192		-515
Loss before (provision for) benefit from income taxes	-14,978		-5,412		-29,229		-11,663
(Provision for) benefit from income taxes	-147		3,347		-291		3,205
Net loss	-15,125		-2,065		-29,520		-8,458
Net loss per share, basic and diluted	($0.41)		($0.06)		($0.80)		($0.25)
Weighted average shares outstanding, basic and diluted (in shares)	37,115		34,625		36,842		34,028
Intangible amortization expense	2,109		660		4,069		1,064
Cost of subscription revenue [Member]	'		'		'		'
Operating expense:	'		'		'		'
Stock-based compensation expense	511		196		923		428
Intangible amortization expense	974		413		1,803		739
Cost of hardware and services revenue [Member]	'		'		'		'
Operating expense:	'		'		'		'
Stock-based compensation expense	144		39		273		75
Research and development [Member]	'		'		'		'
Operating expense:	'		'		'		'
Stock-based compensation expense	2,450		559		4,484		1,064
Intangible amortization expense	24		8		47		16
Sales and marketing [Member]	'		'		'		'
Operating expense:	'		'		'		'
Stock-based compensation expense	2,408		847		4,505		1,621
Intangible amortization expense	1,100		228		2,197		298
General and administrative [Member]	'		'		'		'
Operating expense:	'		'		'		'
Stock-based compensation expense	1,815		511		3,116		1,035
Intangible amortization expense	$11		$11		$22		$11
[1]	Includes intangible amortization expense as follows:Three Months Ended June 30, Six Months Ended June 30, 2014 2013 2014 2013Cost of subscription revenue974 413 1,803 739Research and development24 8 47 16Sales and marketing1,100 228 2,197 298General and administrative11 11 22 11
[2]	Includes stock‑based compensation expense as follows: Three Months Ended June 30, Six Months Ended June 30, 2014 2013 2014 2013Cost of subscription revenue511 196 923 428Cost of hardware and services revenue144 39 273 75Research and development2,450 559 4,484 1,064Sales and marketing2,408 847 4,505 1,621General and administrative1,815 511 3,116 1,035

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Loss (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Net loss	($15,125)	($2,065)	($29,520)	($8,458)
Other comprehensive loss, net of tax	'	'	'	'
Unrealized gains (losses) on investments, net	0	1	0	-13
Comprehensive loss	($15,125)	($2,064)	($29,520)	($8,471)

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Cash Flows (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Adjustments to reconcile net loss to net cash (used in) provided by operating activities	'	'
Net loss	($29,520)	($8,458)
Depreciation and amortization	8,105	3,701
Accretion of investments	15	386
Provision for allowance for doubtful accounts	-5	17
Stock‑based compensation	13,301	4,223
Deferred income taxes and tax credits	-70	-2,535
Change in fair value of contingent earn-out liability	5	0
Amortization of debt issuance costs and accretion of debt discount	4,316	0
Changes in assets and liabilities, net of effect of acquisitions:	'	'
Accounts receivable	-47	-2,841
Inventory	-483	25
Deferred product costs	-995	131
Prepaid expenses and other current assets	-2,226	-129
Noncurrent assets	-78	8
Accounts payable	-462	1,303
Accrued liabilities	-3,376	-3,080
Earn-out payment	-5	0
Deferred rent	1,123	92
Deferred revenue	7,580	7,615
Net cash (used in) provided by operating activities	-2,822	458
Cash flows from investing activities	'	'
Proceeds from sale and maturity of short-term investments	8,000	42,386
Purchase of short-term investments	0	-20,387
Purchase of property and equipment	-6,023	-1,990
Payments to acquire businesses, net of cash acquired	-22,754	-3,771
Net cash provided by investing activities	-20,777	16,238
Cash flows from financing activities	'	'
Proceeds from issuance of common stock, net of repurchases	7,919	9,705
Payments of debt issuance costs	-191	0
Repayments of equipment financing loans	-825	-837
Earn-out payment	-245	0
Net cash provided by financing activities	6,658	8,868
Net increase in cash and cash equivalents	-16,941	25,564
Cash and cash equivalents	'	'
Beginning of period	243,786	39,254
End of period	226,845	64,818
Supplemental disclosure of noncash investing and financing information	'	'
Unpaid purchase of property and equipment	$3,154	$1,857

The_Company_and_Summary_of_Sig

The Company and Summary of Significant Accounting Policies (Notes)	6 Months Ended
	Jun. 30, 2014
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 pioneering security-as-a-service ("SaaS") vendor that enables large and mid-sized organizations through out the world to defend, protect, archive and govern their most sensitive data. The Company’s SaaS platform is comprised of a number of data protection solutions, including threat protection, regulatory compliance, archiving and governance, and secure communication.
	Basis of Presentation and Consolidation
	The accompanying unaudited Condensed Consolidated Financial Statements and condensed footnotes have been prepared in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments considered necessary (consisting only of normal recurring adjustments) for a fair statement of results for the interim periods presented have been included. The results of operations for the three months ended June 30, 2014 are not necessarily indicative of the results to be expected for the year ended December 31, 2014 or for other interim periods or for future years.
	The accompanying unaudited Condensed Consolidated Financial Statements include the accounts of the Company and its wholly-owned subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation. The accompanying Condensed Consolidated Balance Sheet as of December 31, 2013 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. These accompanying Condensed Consolidated Financial Statements should be read in conjunction with the consolidated financial statements and related notes included in the Company's 2013 Annual Report on Form 10-K.
	There have been no material changes to the Company's significant accounting policies described in the Company's Annual Report on Form 10-K for the year ended December 31, 2013, including those described below.
	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 applies ASC 350, "Intangibles—Goodwill and Other" and performs an annual goodwill impairment test during the fourth quarter of the Company's fiscal year and more frequently if an event or circumstances indicates that an impairment may have occurred. For the purposes of impairment testing, the Company has determined that it has 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 an 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 was identified by the Company as of June 30, 2014.
	Intangible assets consist of developed technology, vendor relationships and customer relationships. 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	5
	Non-compete agreements	2	4
	Tradenames and trademarks	1	5
	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. 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.
	The Company applies the provision of ASC 985-605, “Software Revenue Recognition” and related interpretations, to all transactions involving the licensing of software, as well as related support, training, and other professional services. ASC 985-605 requires revenue earned on software arrangements involving multiple elements such as software license, support, training and other professional services to be allocated to each element based on the relative fair values of these elements. The fair value of an element must be based on vendor‑specific objective evidence (“VSOE”) of fair value. VSOE of fair value of each element is based on the price charged when the element is sold separately. Revenue is recognized when all of the following criteria are met as set forth in ASC 985-605:
	•	Persuasive evidence of an arrangement exists,
	•	Delivery has occurred,
	•	The fee is fixed or determinable, and
	•	Collectability is probable.
	The Company has analyzed all of the elements included in its multiple element 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.
	In the accompanying Condensed Consolidated Statements of Operations, revenue is categorized as "subscription" and "hardware and services." Although the Company is unable to separate its multiple elements under the applicable revenue recognition guidance since it does not have sufficient VSOE of fair value for revenue recognition purposes, the Company has used a systematic and rational estimate to classify revenue between subscription and hardware and services. For presentation purposes only, the Company allocates revenue to hardware and services based upon management's best estimate of fair value of such deliverables using a cost plus model. The remaining consideration of the arrangement is then allocated to subscription revenue. Management believes that this methodology provides a reasonable basis to allocate revenue between "subscription" and "hardware and services" for presentation purposes.
	The hosted on-demand service agreements do not provide customers with the right to take possession of the software supporting the hosted service. The Company recognizes revenue from its hosted on-demand services in accordance with ASC 605-20, and as such recognizes revenue when the following criteria are met:
	•	Persuasive evidence of an arrangement exists,
	•	Delivery of the Company’s obligations to its customers has occurred,
	•	Collection of the fees is probable, and
	•	The amount of fees to be paid by the customer is fixed or determinable.
	In October 2009, the FASB amended the accounting guidance for multiple element arrangements (“ASU 2009-13”) to:
	•	Provide updated guidance on whether multiple deliverables exist, how the deliverables in an arrangement should be separated, and how the arrangement consideration should be allocated among its elements;
	•	Require an entity to allocate revenue in an arrangement that has separate units of accounting using best estimated selling price (“BESP”) of deliverables if a vendor does not have VSOE of fair value or third-party evidence of selling price (“TPE”), and
	•	Eliminate the use of the residual method and require an entity to allocate revenue using the relative selling price method to the separate unit of accounting.
	Concurrently, the FASB amended the accounting guidance for revenue recognition (“ASU 2009-14”) to exclude hardware appliances containing software components and hardware components that function together to deliver the hardware appliance’s essential functionality from the scope of the software revenue recognition guidance of ASC 985-605.
	For all arrangements within the scope of these new accounting pronouncements, including the Company’s hosted on-demand services, the Company evaluates each element in a multiple element arrangement to determine whether it represents a separate unit of accounting. An element constitutes a separate unit of accounting when the delivered item has standalone value and delivery of the undelivered element is probable and within the Company’s control. Revenue derived from the licensing of the security-as-a-service platform continues to be accounted for in accordance with the industry specific revenue recognition guidance.
	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 and are recognized when delivered. 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, 2014, 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. Total comprehensive loss has been presented in the accompanying Condensed Consolidated Statements of Comprehensive Loss. The Company had no significant reclassifications out of accumulated other comprehensive loss into net loss for the six months ended June 30, 2014 and 2013.
	Recent Accounting Policies
	In June 2014, the FASB issued ASU 2014-12, "Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period", a new accounting standard update that clarifies the accounting for share-based payments when the terms of an award allow for a performance target to be achieved after an employee completes the requisite period. The amendments require that a performance target that affects vesting and that could be achieved after the requisite period be treated as a performance condition. A company should apply existing guidance in Topic 718 as it relates to awards with performance conditions that affect vesting to account for such awards. Compensation cost should be recognized in the period in which it becomes probable that the performance target will be achieved and should represent the compensation cost attribute to the period(s) for which the requisite service has already been rendered. The new guidance will become effective for the Company on January 1, 2016. Early adoption is permitted and the Company is currently assessing the impact on its consolidated financial statements.
	In May 2014, the FASB issued ASU 2014-09, "Revenue from Contracts with Customers", a new accounting standard update jointly issued with the IASB on revenue recognition. The new guidance provides a single, comprehensive revenue recognition model for all contracts with customers to improve comparability within industries, across industries and across capital markets. Companies are required by the standard to recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled to in an exchange for those goods and services. The new guidance will become effective for the Company on January 1, 2017. Early adoption is not permitted and the Company is currently assessing the impact on its consolidated financial statements.
	In July 2013, the FASB issued ASU 2013-11, "Income Taxes", a new accounting standard update on the financial statement presentation of unrecognized tax benefits. The new guidance provides that a liability related to an unrecognized tax benefit would be presented as a reduction of a deferred tax asset for a net operating loss carryforward, a similar tax loss or a tax credit carryforward if such settlement is required or expected in the event the uncertain tax position is disallowed. The new guidance became effective for the Company on January 1, 2014 and had no material impact to the Company's financial statements.

Acquisitions_Notes

Acquisitions (Notes)	6 Months Ended
	Jun. 30, 2014
Acquisitions [Abstract]	'
Acquisitions	'
	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 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.
	In 2014 and 2013, the Company acquired a total of six companies (collectively, the "Acquisitions") which are further described below.
	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.
	At June 30, 2014, the Company had provisionally estimated fair values for the acquired tangible and identifiable intangible assets and liabilities assumed at the NetCitadel Acquisition Date. The amounts reported were considered provisional as the Company was completing the valuation work to determine the fair value of 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 NetCitadel Acquisition Date. Revenue from NetCitadel was immaterial for the three months ended June 30, 2014.
	At the NetCitadel Acquisition Date, the Company paid $22,754 in cash consideration, net of cash acquired. 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 Quarterly Report on Form 10-Q. The Company incurred $345 in acquisition-related costs which were recorded in operating expenses for the six months ended June 30, 2014.
	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
		Fair Value in USD			Useful Life (in years)
	Tangible assets acquired	$	14		N/A
	Liabilities assumed	(1,270		)	N/A
	Customer relationships	100			5
	Core/developed technology	5,500			5
	Goodwill	18,387			Indefinite
		$	22,731
	Sendmail, Inc.
	On October 1, 2013 (the "Sendmail Acquisition Date"), the Company acquired Sendmail, Inc. ("Sendmail"), a leading provider of messaging infrastructure solutions to enterprises whose solutions ensure global email connectivity, routing and message delivery between people, systems and applications located on-premise, in-cloud or on mobile devices. The Company paid $12,463 in cash consideration, net of cash acquired and debts paid. Of the cash consideration paid, $3,422 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. As part of the acquisition, the Company assumed and paid off $7,933 in long-term debt on the Sendmail Acquisition Date.
	Armorize Technologies, Inc.
	On September 5, 2013 (the "Armorize Acquisition Date"), the Company acquired Armorize Technologies, Inc. ("Armorize"), a Taiwan-based developer and retailer of leading cloud-based SaaS anti-malware products. The Company paid $24,215 in cash consideration, net of cash acquired. Of the cash consideration paid, $3,750 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.
	Abaca Technology Corporation
	On July 19, 2013 (the "Abaca Technology Acquisition Date"), the Company acquired Abaca Technology Corporation ("Abaca Technology"), who specializes in email filtering and protection algorithms and their cloud-based, in-memory threat scoring technologies. The Company paid $23 in cash consideration, net of cash acquired. The purchase consideration included an additional amount of $1,520 which was held back to secure contingent liabilities related to indemnification obligations and has not been released as of the filing date of this Quarterly Report on Form 10-Q.
	eDynamics, LLC
	On July 10, 2013 (the "eDynamics Acquisition Date"), the Company purchased substantially all of the business intellectual property and assumed certain liabilities of eDynamics, LLC ("eDynamics"), a social media archiving company, for $500 in cash consideration. The Company also agreed to pay earn-out consideration ("Acquisition-related contingent earn-out liability") of up to $600 through April 2014, such liability being contingent upon the achievement of specified product development milestones. The purchase consideration also included an additional amount of $100, which was held back to secure any claims that may arise in the 12-month period after the eDynamics Acquisition Date. The Company paid $350 of the Acquisition-related contingent earn-out liability since the eDynamics Acquisition Date and has paid the remaining amounts in full at the time of the filing of this Quarterly Report on Form 10-Q.
	Mail Distiller Limited
	On April 5, 2013 (the "Mail Distiller Acquisition Date"), acquired Mail Distiller Limited, a Northern Ireland Company ("Mail Distiller"), a European-based provider of SaaS email security solutions. The Company paid $3,771 in cash consideration, which was net of cash acquired. The purchase consideration included an additional amount of $669 held back to secure indemnification obligations, which was released during the three months ended June 30, 2014.
	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, 2014 and 2013 for NetCitadel, which was acquired during the second quarter of 2014, and Mail Distiller, which was acquired during the second quarter of 2013. Adjustments were made to give effect to pro forma events that are directly attributable to NetCitadel and Mail Distiller such as amortization expense from acquired intangible assets, acquisition-related transaction costs and, if any, related tax effects. 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 the two acquisitions. 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 NetCitadel had occurred on January 1, 2013 and Mail Distiller had occurred on January 1, 2012, nor are they indicative of future results of operations:
		Three Months Ended							Six Months Ended
		June 30,							June 30,
		2014				2013			2014			2013
	Total revenue	$	46,401			$	31,838		$	89,176		$	62,817
	Net loss	(15,369		)		(3,382		)	(31,112		)	(12,332		)
	Basic and diluted loss per share	$	(0.41	)		$	(0.10	)	$	(0.84	)	$	(0.36	)
	The unaudited pro forma financial information includes non-recurring acquisition-related transaction cost of $345 for the six months ended June 30, 2013.

Goodwill_and_Intangible_Assets

Goodwill and Intangible Assets (Notes)	6 Months Ended
	Jun. 30, 2014
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, 2013	$	63,764
	Add: Goodwill from acquisitions	18,387
	Less: Other adjustments to Goodwill	(139		)
	Balance at June 30, 2014	$	82,012
	The goodwill balance as of June 30, 2014 was the result of the acquisitions of Fortiva, Inc., Secure Data in Motion, Inc., Everyone.net, Inc., Spam and Open Relay Blocking System from GFI Software Ltd., NextPage, Inc., Mail Distiller, eDynamics, Abaca, Armorize, Sendmail and NetCitadel.
	Intangible Assets
	Intangible assets, excluding goodwill, consisted of the following:
		30-Jun-14								December 31, 2013
		Gross			Accumulated			Net		Gross		Accumulated			Net
		Carrying			Amortization			Carrying		Carrying		Amortization			Carrying
		Amount						Amount		Amount					Amount
	Developed technology	$	34,968		$	(19,185	)	$	15,783	$	29,468	$	(17,383	)	$	12,085
	Customer relationships	13,382			(5,767		)	7,615		13,282		(3,726		)	9,556
	Non-compete agreements	804			(316		)	488		804		(170		)	634
	Trademark and patents	806			(185		)	621		806		(105		)	701
		$	49,960		$	(25,453	)	$	24,507	$	44,360	$	(21,384	)	$	22,976
	Amortization expense of intangible assets totaled $2,109 and $660, respectively, for the three months ended June 30, 2014 and 2013, and $4,069 and $1,064, respectively, for the six months ended June 30, 2014 and 2013.
	Future estimated amortization costs of intangible assets as of June 30, 2014 are presented below:
	Year ending December 31,
	2014, remainder	$	4,494
	2015	8,220
	2016	5,887
	2017	2,742
	2018	2,295
	Thereafter	869
		$	24,507

Fair_Value_Measurements_and_In

Fair Value Measurements and Investments (Notes)	6 Months Ended
	Jun. 30, 2014
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 bonds and agency debt securities, commercial paper, and certificates of deposit.
	•	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.
	In connection with the acquisition of eDynamics in 2013, a liability was recognized on the eDynamics Acquisition Date for the estimate of the fair value of the Company's contingent earn-out payments related to eDynamics. The Company determined the fair value of the Acquisition-related contingent earn-out liability based on the probability-based attainment of product development milestones. Any changes to the variables and assumptions could significantly impact the estimated fair values recorded for the liability, resulting in significant charges to the accompanying Condensed Consolidated Statements of Operations. The fair value measurements are based on significant inputs not observable in the market and thus represent Level 3 measurements, which reflect the Company's own assumptions concerning achievement of the product development milestones of eDynamics, in measuring the fair value of the Acquisition-related contingent earn-out liability.
	The following tables summarize, for each category of assets or liabilities carried at fair value, the respective fair value as of June 30, 2014 and December 31, 2013 and the classification by level of input within the fair value hierarchy:
		Balance as of				Quoted Prices		Significant		Unobservable
		June 30,				in Active		Other		Inputs
		2014				Markets for		Observable		(Level 3)
						Identical		Inputs
						Assets		(Level 2)
						(Level 1)
	Assets
	Cash equivalents:
	Money market funds	$	198,571			$	198,571	$	—	$	—
	Liabilities
	Acquisition-related contingent earn-out liability	$	250			$	—	$	—	$	250
		Balance as of				Quoted Prices		Significant		Unobservable
		December 31,				in Active		Other		Inputs
		2013				Markets for		Observable		(Level 3)
						Identical		Inputs
						Assets		(Level 2)
						(Level 1)
	Assets
	Cash equivalents:
	Money market funds	$	215,094			$	215,094	$	—	$	—
	Short-term investments:
	Corporate debt securities	6,015				—		6,015		—
	Certificates of deposit	2,000				—		2,000		—
	Total financial assets	$	223,109			$	215,094	$	8,015	$	—
	Liabilities
	Acquisition-related contingent earn-out liability	$	495			$	—	$	—	$	495
	Based on quoted market prices as of June 30, 2014, the fair value of the 1.25% Convertible Senior Notes was approximately $24,129, determined using Level 2 inputs as they are not actively traded in markets.
	The following table represents a reconciliation of the Acquisition-related contingent earn-out liability measured at fair value on a recurring basis, using significant unobservable inputs (Level 3) for the six months ended June 30, 2014:
			Fair Value Measurements
			Using Significant Unobservable Inputs
			(Level 3)
	Balance at December 31, 2013		$	495
	Payments during the period		(250		)
	Adjustments to fair value during the period recorded in General and administrative expenses		5
	Balance at June 30, 2014		$	250
	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 basis of the Company’s cash and cash equivalents and available-for-sale investments approximated their fair values as of June 30, 2014 and December 31, 2013 as follows:
			June 30,
			2014
	Cash and cash equivalents:
	Cash		$	28,274
	Money market funds		198,571
	Total		$	226,845
			December 31,
			2013
	Cash and cash equivalents:
	Cash		$	28,692
	Money market funds		215,094
	Total		$	243,786
	Short-term investments:
	Corporate debt securities		$	6,015
Certificate of deposit		2,000
Total		$	8,015
As of June 30, 2014, the Company had no outstanding short-term investments.

Commitments_and_Contingencies_

Commitments and Contingencies (Notes)	6 Months Ended
	Jun. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	Commitments and Contingencies
	Operating Leases
	In March 2014, the Company entered into an amendment to extend the lease agreement of its corporate offices located in Sunnyvale, California through December 31, 2019, which included an expansion of office space. Overall, the Company has noncancellable operating leases with various expiration dates through June 2024.
	Rent expense was $860 and $403, respectively, for the three months ended June 30, 2014 and 2013, and $1,398 and $803, respectively, for the six months ended June 30, 2014 and 2013.
	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, 2014, future annual minimum lease payments under noncancellable operating and capital leases were as follows:
		Capital			Operating
		Leases			Leases
	Year ending December 31,
	2014, remainder	$	9		$	2,000
	2015	11			4,622
	2016	—			3,822
	2017	—			2,965
	2018	—			2,822
	Thereafter	—			3,152
	Total minimum lease payments	20			$	19,383
	Less: Amount representing interest	(1		)
	Present value of capital lease obligations	19
	Less: current portion	(17		)
	Long-term portion of capital lease obligations	$	2
	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 provide no basis or facts in support of this sum. On June 12, 2014, at the mandatory case management conference, the court ordered that the claims construction hearing be held in May 2015 and trial be set for January 2016, subject to later adjustment or delay. Based on the early stage of the claims 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 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, 2014
Convertible Senior Notes [Abstract]	'
Convertible Senior Notes	'
	Convertible Senior Notes
	On December 11, 2013, the Company issued $175,000 principal amount of 1.25% Convertible Senior Notes (the "Notes") due 2018 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 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 Notes offering were approximately $195,446. The Company intends to 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 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 Notes are unsecured and rank senior in right of payment to any indebtedness expressly subordinated in right of payment to the 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 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 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 redeem all or a portion of the Notes at 100% of the principal amount, plus any accrued and unpaid interest, under certain conditions. The Company may redeem the Notes in shares of the Company’s common stock, cash, or some combination of each.
	Prior to June 15, 2018, the 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 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 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 Notes also have the right to require the Company to repurchase all or a portion of the 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 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 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 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 debt issuance costs were capitalized and recorded as deferred offering costs in other noncurrent assets and are being amortized to interest expense using the effective interest rate method from the issuance date through December 15, 2018. The equity issuance costs were recorded as a decrease to additional paid-in capital at the issuance date.
	At June 30, 2014, the net carrying amount of the liability component of the Notes consists of:
	Liability component:
	Principal	$	201,250
	Less: debt discount, net of amortization	(44,032		)
	Net carrying amount	$	157,218
	Equity component (1)	$	43,293
	(1) Recorded in the accompanying Condensed Consolidated Balance Sheets as additional paid-in capital, net of the $1,285 issuance costs in equity
	For the three and six months ended June 30, 2014, the Company incurred the following interest expense related to the Notes:
		Three Months Ended			Six Months Ended
		30-Jun-14
	1.25% coupon	$	624		$	1,253
	Amortization of debt discount	2,160			4,291
	Amortization of debt issuance costs	13			25
		$	2,797		$	5,569

Debt_Notes

Debt (Notes)	6 Months Ended
	Jun. 30, 2014
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 is equal to prime rate plus 0.5%. As of June 30, 2014, the interest rate on the outstanding advances was 4.5%. The Company had the ability to draw down on this equipment line through April 19, 2012. Each drawn amount is due 48 months after funding. Borrowings outstanding under the equipment loan at June 30, 2014 were $1,505. Equipment financed under this loan arrangement is collateralized by the respective assets underlying the loan. The terms of the loan restrict the Company’s ability to pay dividends. The loan includes a covenant that requires the Company to maintain cash and cash equivalents plus net accounts receivable of at least two times the amount of all outstanding indebtedness, excluding the impact from the Notes. As of June 30, 2014, the Company was in compliance with the financial covenant.
	Interest expense was $23 and $38, respectively, for the three months ended June 30, 2014 and 2013, and $51 and $80, respectively, for the six months ended June 30, 2014 and 2013.
	At June 30, 2014, the remaining repayment commitments related to the equipment loans are as follows:
	Year ending December 31,
	2014, remainder	$	821
	2015	684
		$	1,505

Common_Stock_Notes

Common Stock (Notes)	6 Months Ended
	Jun. 30, 2014
Equity [Abstract]	'
Stockholders' Equity	'
	Common Stock
	As of June 30, 2014, 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. The Company had 37,299 and 36,140 shares, respectively, issued and outstanding at June 30, 2014 and December 31, 2013.
	Number of shares of common stock reserved for future issuance was as follows:
		As of	As of
		June 30,	December 31,
		2014	2013
	Shares available for future grant under the stock plans	5,037	4,584
	Options outstanding under stock plans	6,482	7,223
	Shares available for future issuance under ESPP	1,026	759
	Common stock issuable upon exercise of warrant and settlement of outstanding restricted stock units	2,236	1,216
	Common stock issuable upon conversion of the convertible senior notes	5,158	5,158
	Total shares reserved	19,939	18,940

Stock_Equity_Plans_Notes

Stock Equity Plans (Notes)	6 Months Ended
	Jun. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
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 initial public offering, 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 shares. 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.
	Under the 2002 and 2012 Plans, the term of an option grant shall not exceed 10 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. 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. As of June 30, 2014, 5,037 shares were available for future grant.
	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, an assumed risk-free interest rate and the estimated forfeitures of unvested stock options. To the extent actual forfeitures differ from the estimates, the difference will be recorded as a cumulative adjustment in the period estimates are revised. 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 $19.51 and $10.58, respectively, during the three months ended June 30, 2014 and 2013, and $19.88 and $8.19, respectively, during the six months ended June 30, 2014 and 2013. 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				Six Months Ended
		June 30,				June 30,
		2014		2013		2014		2013
	Expected life (in years)	5.31-6.08		5.9		5.31-6.08		6.04
	Volatility	54% - 58%		58	%	54% - 58%		58	%
	Risk-free interest rate	1.8% - 1.9%		1.1	%	1.8% - 1.9%		1.1	%
	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. Expected forfeitures are estimated based on the Company's historical experience.
	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		Weighted Average			Weighted Average		Aggregate
		Shares		Exercise Price			Remaining Contractual Term		Intrinsic
							(in years)		Value
	Balance at December 31, 2013	7,223		$	8.17		6.82		$	180,543
	Options granted	500		36.06
	Options exercised	(1,029	)	6.28
	Options forfeited and canceled	(212	)	15.19
	Balance at June 30, 2014	6,482		$	10.4		6.67		$	175,472
	The total intrinsic value of options exercised was $32,192 and $24,063, respectively, for the six months ended June 30, 2014 and 2013. Total cash proceeds from such option exercises were $6,465 and $8,543, respectively, for the six months ended June 30, 2014 and 2013.
	The fair value of option grants that vested was $2,909 and $1,565, respectively, during the three months ended June 30, 2014 and 2013, and $5,870 and $3,768, respectively, during the six months ended June 30, 2014 and 2013.
	As of June 30, 2014, the Company had unamortized stock-based compensation expense of $19,481 related to stock options, that will be recognized net of forfeitures over the average remaining vesting term of the options of 2.28 years.
	Restricted Stock Units
	A summary of the status of RSUs awarded and unvested under the stock option plans as of June 30, 2014 is presented below:
		RSUs Outstanding
		Number of		Granted Fair Value Per Unit
		Shares
	Awarded and unvested at December 31, 2013	1,214		$	29.57
	Awards granted	1,155		34.49
	Awards vested	(55	)	37.48
	Awards forfeited	(78	)	29.66
	Awarded and unvested at June 30, 2014	2,236		$	32.01
	As of June 30, 2014, there was $47,888 of unamortized stock-based compensation expense related to unvested RSUs, which are expected to be recognized over a weighted average period of 3.42 years.
	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 was 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, 2014, there were 1,026 shares of the Company's common stock available for future issuance under the ESPP.
	There were no stock purchase rights granted under the ESPP during the six months ended June 30, 2014 and 2013.
	The fair value of the option component of the ESPP shares was estimated at the grant date using the Black-Scholes option pricing model with the following weighted average assumptions:
		Three Months Ended				Six Months Ended
		June 30,				June 30,
		2014		2013		2014		2013
	Expected life (in years)	0.5		0.5		0.5		0.5
	Volatility	52	%	40	%	52	%	40	%
	Risk-free interest rate	0.05	%	0.08	%	0.05	%	0.08	%
	Dividend yield	—	%	—	%	—	%	—	%
	As of June 30, 2014, the Company expects to recognize $670 of the total unamortized compensation cost related to employee purchases under the ESPP over a weighted average period of 0.37 years.

Net_Loss_per_Share_Notes

Net Loss per Share (Notes)	6 Months Ended
	Jun. 30, 2014
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 that were exercised 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 of common stock for the periods presented because including them would have been anti-dilutive:
		As of June 30,
		2014	2013
	Stock options to purchase common stock	6,482	8,248
	Employee stock purchase plan	106	102
	Common stock subject to repurchase	—	2
	Restricted stock units	2,236	39
	Convertible senior notes	5,158	—
	Total	13,982	8,391

Segment_Reporting_Notes

Segment Reporting (Notes)	6 Months Ended
	Jun. 30, 2014
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, or decision making group, 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 and as a result, the Company concluded that there is only 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				Six Months Ended
		June 30,				June 30,
		2014		2013		2014		2013
	Total revenue by solution:
	Privacy, Protection and Security	$	35,549	$	22,609	68,152		44,375
	Archiving and Governance	10,849		9,218		20,950		18,216
	Total revenue	$	46,398	$	31,827	$	89,102	$	62,591
		Three Months Ended				Six Months Ended
		June 30,				June 30,
		2014		2013		2014		2013
	Total revenue:
	United States	$	38,012	$	26,288	$	73,229	$	51,797
	Rest of world	8,386		5,539		15,873		10,794
	Total revenue	$	46,398	$	31,827	$	89,102	$	62,591
		As of		As of
		June 30,		December 31,
		2014		2013
	Long-lived assets:
	United States	$	12,445	$	9,425
	Rest of world	2,892		1,796
	Total long‑lived assets	$	15,337	$	11,221

Income_Taxes_Notes

Income Taxes (Notes)	6 Months Ended
	Jun. 30, 2014
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, 2014 was $147 and $291 on pre-tax losses of $14,978 and $29,229, respectively. Income tax benefit for the three and six months ended June 30, 2013 was $3,347 and $3,205 on pre-tax losses of $5,412 and $11,663, respectively. The income tax rate for the three and six months ended June 30, 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 income tax rate for the three and six months ended June 30, 2013 also varied from the United States statutory rate due to the recognition of a $3,392 deferred income tax benefit related to the release of a valuation allowance in a certain foreign jurisdiction which occurred during the period.
	The Company's effective tax rate for the six months ended June 30, 2014 decreased to 1.0% from 27.5% for the same prior year period. The prior period's effective tax rate was impacted the recognition of a $3,392 deferred income tax benefit related to the release of a valuation allowance in a foreign jurisdiction.
	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, 2014, the Company's gross uncertain tax benefits totaled $3,942, excluding related accrued interest and penalties of $239. As of June 30, 2014, $1,517 of the Company's uncertain tax benefits, including related accrued interest and penalties, would affect the effective tax rate if recognized. During the three months ended June 30, 2014, the Company's gross uncertain tax benefits increased $84. The increase is comprised of a $75 increase for tax positions taken in the current period, a $30 increase for tax positions taken in prior period, and a $21 decrease related to statue of expiration.
	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.

The_Company_and_Summary_of_Sig1

The Company and Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2014
Accounting Policies [Abstract]	'
Basis of Presentation and Consolidation	'
	Basis of Presentation and Consolidation
	The accompanying unaudited Condensed Consolidated Financial Statements and condensed footnotes have been prepared in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments considered necessary (consisting only of normal recurring adjustments) for a fair statement of results for the interim periods presented have been included. The results of operations for the three months ended June 30, 2014 are not necessarily indicative of the results to be expected for the year ended December 31, 2014 or for other interim periods or for future years.
	The accompanying unaudited Condensed Consolidated Financial Statements include the accounts of the Company and its wholly-owned subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation. The accompanying Condensed Consolidated Balance Sheet as of December 31, 2013 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. These accompanying Condensed Consolidated Financial Statements should be read in conjunction with the consolidated financial statements and related notes included in the Company's 2013 Annual Report on Form 10-K.
	There have been no material changes to the Company's significant accounting policies described in the Company's Annual Report on Form 10-K for the year ended December 31, 2013, including those described below
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 applies ASC 350, "Intangibles—Goodwill and Other" and performs an annual goodwill impairment test during the fourth quarter of the Company's fiscal year and more frequently if an event or circumstances indicates that an impairment may have occurred. For the purposes of impairment testing, the Company has determined that it has 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 an 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 was identified by the Company as of June 30, 2014.
	Intangible assets consist of developed technology, vendor relationships and customer relationships. 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	5
	Non-compete agreements	2	4
	Tradenames 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. 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.
	The Company applies the provision of ASC 985-605, “Software Revenue Recognition” and related interpretations, to all transactions involving the licensing of software, as well as related support, training, and other professional services. ASC 985-605 requires revenue earned on software arrangements involving multiple elements such as software license, support, training and other professional services to be allocated to each element based on the relative fair values of these elements. The fair value of an element must be based on vendor‑specific objective evidence (“VSOE”) of fair value. VSOE of fair value of each element is based on the price charged when the element is sold separately. Revenue is recognized when all of the following criteria are met as set forth in ASC 985-605:
	•	Persuasive evidence of an arrangement exists,
	•	Delivery has occurred,
	•	The fee is fixed or determinable, and
	•	Collectability is probable.
	The Company has analyzed all of the elements included in its multiple element 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.
	In the accompanying Condensed Consolidated Statements of Operations, revenue is categorized as "subscription" and "hardware and services." Although the Company is unable to separate its multiple elements under the applicable revenue recognition guidance since it does not have sufficient VSOE of fair value for revenue recognition purposes, the Company has used a systematic and rational estimate to classify revenue between subscription and hardware and services. For presentation purposes only, the Company allocates revenue to hardware and services based upon management's best estimate of fair value of such deliverables using a cost plus model. The remaining consideration of the arrangement is then allocated to subscription revenue. Management believes that this methodology provides a reasonable basis to allocate revenue between "subscription" and "hardware and services" for presentation purposes.
	The hosted on-demand service agreements do not provide customers with the right to take possession of the software supporting the hosted service. The Company recognizes revenue from its hosted on-demand services in accordance with ASC 605-20, and as such recognizes revenue when the following criteria are met:
	•	Persuasive evidence of an arrangement exists,
	•	Delivery of the Company’s obligations to its customers has occurred,
	•	Collection of the fees is probable, and
	•	The amount of fees to be paid by the customer is fixed or determinable.
	In October 2009, the FASB amended the accounting guidance for multiple element arrangements (“ASU 2009-13”) to:
	•	Provide updated guidance on whether multiple deliverables exist, how the deliverables in an arrangement should be separated, and how the arrangement consideration should be allocated among its elements;
	•	Require an entity to allocate revenue in an arrangement that has separate units of accounting using best estimated selling price (“BESP”) of deliverables if a vendor does not have VSOE of fair value or third-party evidence of selling price (“TPE”), and
	•	Eliminate the use of the residual method and require an entity to allocate revenue using the relative selling price method to the separate unit of accounting.
	Concurrently, the FASB amended the accounting guidance for revenue recognition (“ASU 2009-14”) to exclude hardware appliances containing software components and hardware components that function together to deliver the hardware appliance’s essential functionality from the scope of the software revenue recognition guidance of ASC 985-605.
	For all arrangements within the scope of these new accounting pronouncements, including the Company’s hosted on-demand services, the Company evaluates each element in a multiple element arrangement to determine whether it represents a separate unit of accounting. An element constitutes a separate unit of accounting when the delivered item has standalone value and delivery of the undelivered element is probable and within the Company’s control. Revenue derived from the licensing of the security-as-a-service platform continues to be accounted for in accordance with the industry specific revenue recognition guidance.
	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 and are recognized when delivered. 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, 2014, 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. Total comprehensive loss has been presented in the accompanying Condensed Consolidated Statements of Comprehensive Loss. The Company had no significant reclassifications out of accumulated other comprehensive loss into net loss for the six months ended June 30, 2014 and 2013.
New Accounting Pronouncements	'
	Recent Accounting Policies
	In June 2014, the FASB issued ASU 2014-12, "Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period", a new accounting standard update that clarifies the accounting for share-based payments when the terms of an award allow for a performance target to be achieved after an employee completes the requisite period. The amendments require that a performance target that affects vesting and that could be achieved after the requisite period be treated as a performance condition. A company should apply existing guidance in Topic 718 as it relates to awards with performance conditions that affect vesting to account for such awards. Compensation cost should be recognized in the period in which it becomes probable that the performance target will be achieved and should represent the compensation cost attribute to the period(s) for which the requisite service has already been rendered. The new guidance will become effective for the Company on January 1, 2016. Early adoption is permitted and the Company is currently assessing the impact on its consolidated financial statements.
	In May 2014, the FASB issued ASU 2014-09, "Revenue from Contracts with Customers", a new accounting standard update jointly issued with the IASB on revenue recognition. The new guidance provides a single, comprehensive revenue recognition model for all contracts with customers to improve comparability within industries, across industries and across capital markets. Companies are required by the standard to recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled to in an exchange for those goods and services. The new guidance will become effective for the Company on January 1, 2017. Early adoption is not permitted and the Company is currently assessing the impact on its consolidated financial statements.
	In July 2013, the FASB issued ASU 2013-11, "Income Taxes", a new accounting standard update on the financial statement presentation of unrecognized tax benefits. The new guidance provides that a liability related to an unrecognized tax benefit would be presented as a reduction of a deferred tax asset for a net operating loss carryforward, a similar tax loss or a tax credit carryforward if such settlement is required or expected in the event the uncertain tax position is disallowed. The new guidance became effective for the Company on January 1, 2014 and had no material impact to the Company's financial statements.

The_Company_and_Summary_of_Sig2

The Company and Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2014
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	5
	Non-compete agreements	2	4
	Tradenames and trademarks	1	5

Acquisitions_Tables

Acquisitions (Tables)	6 Months Ended
	Jun. 30, 2014
Acquisitions [Abstract]	'
Schedule of purchase price [Table Text Block]	'
	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
		Fair Value in USD			Useful Life (in years)
	Tangible assets acquired	$	14		N/A
	Liabilities assumed	(1,270		)	N/A
	Customer relationships	100			5
	Core/developed technology	5,500			5
	Goodwill	18,387			Indefinite
		$	22,731
Pro forma information [Table Text Block]	'
	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 NetCitadel had occurred on January 1, 2013 and Mail Distiller had occurred on January 1, 2012, nor are they indicative of future results of operations:
		Three Months Ended							Six Months Ended
		June 30,							June 30,
		2014				2013			2014			2013
	Total revenue	$	46,401			$	31,838		$	89,176		$	62,817
	Net loss	(15,369		)		(3,382		)	(31,112		)	(12,332		)
	Basic and diluted loss per share	$	(0.41	)		$	(0.10	)	$	(0.84	)	$	(0.36	)

Goodwill_and_Intangible_Assets1

Goodwill and Intangible Assets (Tables)	6 Months Ended
	Jun. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Schedule of goodwill [Table Text Block]	'
	The goodwill activity and balances are presented below:
	Balance at December 31, 2013	$	63,764
	Add: Goodwill from acquisitions	18,387
	Less: Other adjustments to Goodwill	(139		)
	Balance at June 30, 2014	$	82,012
Components of intangible assets excluding goodwill [Table Text Block]	'
	Intangible assets, excluding goodwill, consisted of the following:
		30-Jun-14								December 31, 2013
		Gross			Accumulated			Net		Gross		Accumulated			Net
		Carrying			Amortization			Carrying		Carrying		Amortization			Carrying
		Amount						Amount		Amount					Amount
	Developed technology	$	34,968		$	(19,185	)	$	15,783	$	29,468	$	(17,383	)	$	12,085
	Customer relationships	13,382			(5,767		)	7,615		13,282		(3,726		)	9,556
	Non-compete agreements	804			(316		)	488		804		(170		)	634
	Trademark and patents	806			(185		)	621		806		(105		)	701
		$	49,960		$	(25,453	)	$	24,507	$	44,360	$	(21,384	)	$	22,976
Future estimated amortization costs of intangible assets [Table Text Block]	'
	Amortization expense of intangible assets totaled $2,109 and $660, respectively, for the three months ended June 30, 2014 and 2013, and $4,069 and $1,064, respectively, for the six months ended June 30, 2014 and 2013.
	Future estimated amortization costs of intangible assets as of June 30, 2014 are presented below:
	Year ending December 31,
	2014, remainder	$	4,494
	2015	8,220
	2016	5,887
	2017	2,742
	2018	2,295
	Thereafter	869
		$	24,507

Fair_Value_Measurements_and_In1

Fair Value Measurements and Investments (Tables)	6 Months Ended
	Jun. 30, 2014
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, 2014 and December 31, 2013 and the classification by level of input within the fair value hierarchy:
		Balance as of				Quoted Prices		Significant		Unobservable
		June 30,				in Active		Other		Inputs
		2014				Markets for		Observable		(Level 3)
						Identical		Inputs
						Assets		(Level 2)
						(Level 1)
	Assets
	Cash equivalents:
	Money market funds	$	198,571			$	198,571	$	—	$	—
	Liabilities
	Acquisition-related contingent earn-out liability	$	250			$	—	$	—	$	250
		Balance as of				Quoted Prices		Significant		Unobservable
		December 31,				in Active		Other		Inputs
		2013				Markets for		Observable		(Level 3)
						Identical		Inputs
						Assets		(Level 2)
						(Level 1)
	Assets
	Cash equivalents:
	Money market funds	$	215,094			$	215,094	$	—	$	—
	Short-term investments:
	Corporate debt securities	6,015				—		6,015		—
	Certificates of deposit	2,000				—		2,000		—
	Total financial assets	$	223,109			$	215,094	$	8,015	$	—
	Liabilities
	Acquisition-related contingent earn-out liability	$	495			$	—	$	—	$	495
Fair value, liabilities measured on recurring basis, unobservable input reconciliation [Table Text Block]	'
	The following table represents a reconciliation of the Acquisition-related contingent earn-out liability measured at fair value on a recurring basis, using significant unobservable inputs (Level 3) for the six months ended June 30, 2014:
			Fair Value Measurements
			Using Significant Unobservable Inputs
			(Level 3)
	Balance at December 31, 2013		$	495
	Payments during the period		(250		)
	Adjustments to fair value during the period recorded in General and administrative expenses		5
	Balance at June 30, 2014		$	250
Fair value of cash and cash equivalents, and investments [Table Text Block]	'
	The cost basis of the Company’s cash and cash equivalents and available-for-sale investments approximated their fair values as of June 30, 2014 and December 31, 2013 as follows:
			June 30,
			2014
	Cash and cash equivalents:
	Cash		$	28,274
	Money market funds		198,571
	Total		$	226,845
			December 31,
			2013
	Cash and cash equivalents:
	Cash		$	28,692
	Money market funds		215,094
	Total		$	243,786
	Short-term investments:
	Corporate debt securities		$	6,015
	Certificate of deposit		2,000
	Total		$	8,015

Commitments_and_Contingencies_1

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Future annual minimum lease payments under noncancelable operating and capital leases [Table Text Block]	'
	At June 30, 2014, future annual minimum lease payments under noncancellable operating and capital leases were as follows:
		Capital			Operating
		Leases			Leases
	Year ending December 31,
	2014, remainder	$	9		$	2,000
	2015	11			4,622
	2016	—			3,822
	2017	—			2,965
	2018	—			2,822
	Thereafter	—			3,152
	Total minimum lease payments	20			$	19,383
	Less: Amount representing interest	(1		)
	Present value of capital lease obligations	19
	Less: current portion	(17		)
	Long-term portion of capital lease obligations	$	2

Convertible_Senior_Notes_Table

Convertible Senior Notes (Tables)	6 Months Ended
	Jun. 30, 2014
Convertible Senior Notes [Abstract]	'
Schedule of liability and equity components of convertible debt [Table Text Block]	'
	At June 30, 2014, the net carrying amount of the liability component of the Notes consists of:
	Liability component:
	Principal	$	201,250
	Less: debt discount, net of amortization	(44,032		)
	Net carrying amount	$	157,218
	Equity component (1)	$	43,293
	(1) Recorded in the accompanying Condensed Consolidated Balance Sheets as additional paid-in capital, net of the $1,285 issuance costs in equity
Schedule of convertible note interest and accretion [Table Text Block]	'
	For the three and six months ended June 30, 2014, the Company incurred the following interest expense related to the Notes:
		Three Months Ended			Six Months Ended
		30-Jun-14
	1.25% coupon	$	624		$	1,253
	Amortization of debt discount	2,160			4,291
	Amortization of debt issuance costs	13			25
		$	2,797		$	5,569

Debt_Tables

Debt (Tables)	6 Months Ended
	Jun. 30, 2014
Debt Disclosure [Abstract]	'
Remaining repayment commitments [Table Text Block]	'
	At June 30, 2014, the remaining repayment commitments related to the equipment loans are as follows:
	Year ending December 31,
	2014, remainder	$	821
	2015	684
		$	1,505

Common_Stock_Tables

Common Stock (Tables)	6 Months Ended
	Jun. 30, 2014
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
		June 30,	December 31,
		2014	2013
	Shares available for future grant under the stock plans	5,037	4,584
	Options outstanding under stock plans	6,482	7,223
	Shares available for future issuance under ESPP	1,026	759
	Common stock issuable upon exercise of warrant and settlement of outstanding restricted stock units	2,236	1,216
	Common stock issuable upon conversion of the convertible senior notes	5,158	5,158
	Total shares reserved	19,939	18,940

Stock_Equity_Plans_Tables

Stock Equity Plans (Tables)	6 Months Ended
	Jun. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
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				Six Months Ended
		June 30,				June 30,
		2014		2013		2014		2013
	Expected life (in years)	5.31-6.08		5.9		5.31-6.08		6.04
	Volatility	54% - 58%		58	%	54% - 58%		58	%
	Risk-free interest rate	1.8% - 1.9%		1.1	%	1.8% - 1.9%		1.1	%
	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		Weighted Average			Weighted Average		Aggregate
		Shares		Exercise Price			Remaining Contractual Term		Intrinsic
							(in years)		Value
	Balance at December 31, 2013	7,223		$	8.17		6.82		$	180,543
	Options granted	500		36.06
	Options exercised	(1,029	)	6.28
	Options forfeited and canceled	(212	)	15.19
	Balance at June 30, 2014	6,482		$	10.4		6.67		$	175,472
Summary of RSUs awarded and unvested under stock option plan [Table Text Block]	'
	A summary of the status of RSUs awarded and unvested under the stock option plans as of June 30, 2014 is presented below:
		RSUs Outstanding
		Number of		Granted Fair Value Per Unit
		Shares
	Awarded and unvested at December 31, 2013	1,214		$	29.57
	Awards granted	1,155		34.49
	Awards vested	(55	)	37.48
	Awards forfeited	(78	)	29.66
	Awarded and unvested at June 30, 2014	2,236		$	32.01

Net_Loss_per_Share_Tables

Net Loss per Share (Tables)	6 Months Ended
	Jun. 30, 2014
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 of common stock for the periods presented because including them would have been anti-dilutive:
		As of June 30,
		2014	2013
	Stock options to purchase common stock	6,482	8,248
	Employee stock purchase plan	106	102
	Common stock subject to repurchase	—	2
	Restricted stock units	2,236	39
	Convertible senior notes	5,158	—
	Total	13,982	8,391

Segment_Reporting_Tables

Segment Reporting (Tables)	6 Months Ended
	Jun. 30, 2014
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				Six Months Ended
		June 30,				June 30,
		2014		2013		2014		2013
	Total revenue by solution:
	Privacy, Protection and Security	$	35,549	$	22,609	68,152		44,375
	Archiving and Governance	10,849		9,218		20,950		18,216
	Total revenue	$	46,398	$	31,827	$	89,102	$	62,591
Total revenue and long-lived assets by geographic area [Table Text Block]	'
		Three Months Ended				Six Months Ended
		June 30,				June 30,
		2014		2013		2014		2013
	Total revenue:
	United States	$	38,012	$	26,288	$	73,229	$	51,797
	Rest of world	8,386		5,539		15,873		10,794
	Total revenue	$	46,398	$	31,827	$	89,102	$	62,591
		As of		As of
		June 30,		December 31,
		2014		2013
	Long-lived assets:
	United States	$	12,445	$	9,425
	Rest of world	2,892		1,796
	Total long‑lived assets	$	15,337	$	11,221

The_Company_and_Summary_of_Sig3

The Company and Summary of Significant Accounting Policies - Goodwill and Intangible Assets (Details) (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014
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] | 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	'5 years
Maximum [Member] | Noncompete agreements [Member]	'
Intangible assets:	'
Estimated life of intangible assets	'4 years
Maximum [Member] | Trademarks and trade names [Member]	'
Intangible assets:	'
Estimated life of intangible assets	'5 years

Acquisitions_20132014_Details

Acquisitions - 2013-2014 (Details) (USD $)

6 Months Ended

18 Months Ended

0 Months Ended

12 Months Ended

0 Months Ended

In Thousands, unless otherwise specified

Jun. 30, 2014

Jun. 30, 2013

Jun. 30, 2014

Dec. 31, 2013

13-May-14

Oct. 01, 2013

Sep. 05, 2013

Jul. 10, 2013

Jul. 19, 2013

Apr. 05, 2013

Jun. 30, 2014

Jul. 10, 2013

Jul. 10, 2013

13-May-14

13-May-14

NetCitadel [Member]

Sendmail [Member]

Armorize [Member]

eDynamics [Member]

Abaca Technologies [Member]

Mail Distiller [Member]

Earn-out consideration [Member]

Earn-out consideration [Member]

Indemnification obligations [Member]

Customer relationships [Member]

Developed technology rights [Member]

eDynamics [Member]

eDynamics [Member]

eDynamics [Member]

NetCitadel [Member]

NetCitadel [Member]

Business acquisitions

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of businesses acquired

'

'

6

'

'

'

'

'

'

'

'

'

'

'

'

Payments to acquire businesses, net of cash acquired

$22,754

$3,771

'

'

$22,754

$12,463

$24,215

$500

$23

$3,771

'

'

'

'

'

Contingent consideration arrangements, range of outcomes, value, high

'

'

'

'

3,369

3,422

3,750

'

1,520

'

'

600

100

'

'

Recognized identifiable assets acquired and liabilities assumed, noncurrent liabilities, long-term debt

'

'

'

'

'

7,933

'

'

'

'

'

'

'

'

'

Acquisition-related costs

345

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Recognized identifiable assets acquired and liabilities assumed, assets

'

'

'

'

14

'

'

'

'

'

'

'

'

'

'

Recognized identifiable assets acquired and liabilities assumed, liabilities

'

'

'

'

-1,270

'

'

'

'

'

'

'

'

'

'

Recognized identifiable assets acquired and liabilities assumed, finite-lived intangibles

'

'

'

'

'

'

'

'

'

'

'

'

'

100

5,500

Acquired finite-lived intangible assets, weighted average useful life

'

'

'

'

'

'

'

'

'

'

'

'

'

'5 years

'5 years

Goodwill

82,012

'

82,012

63,764

18,387

'

'

'

'

'

'

'

'

'

'

Recognized identifiable assets acquired and liabilities assumed, net

'

'

'

'

22,731

'

'

'

'

'

'

'

'

'

'

Contingent consideration at fair value subsequent payments

'

'

'

'

'

'

'

'

'

'

350

'

'

'

'

Liabilities arising from contingencies, amount recognized

'

'

'

'

'

'

'

'

'

$669

'

'

'

'

'

Acquisitions_Pro_Forma_Financi

Acquisitions - Pro Forma Financial Information (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]	'	'	'	'
Total revenue	$46,401	$31,838	$89,176	$62,817
Net loss	-15,369	-3,382	-31,112	-12,332
Basic and diluted net loss per share (in dollars per share)	($0.41)	($0.10)	($0.84)	($0.36)
Acquisition-related costs	'	'	345	'
Acquisition-related costs [Member]	'	'	'	'
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]	'	'	'	'
Acquisition-related costs	'	'	'	$345

Goodwill_and_Intangible_Assets2

Goodwill and Intangible Assets - Goodwill (Details) (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014
Goodwill activity and balances	'
Opening balance	$63,764
Add: Goodwill from acquisitions	18,387
Less: Other adjustments to goodwill	-139
Closing balance	$82,012

Goodwill_and_Intangible_Assets3

Goodwill and Intangible Assets - Intangible Assets (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Intangible assets excluding goodwill:	'	'	'	'	'
Finite-lived intangible assets, gross carrying amount	$49,960	'	$49,960	'	$44,360
Finite-lived intangible assets, accumulated amortization	-25,453	'	-25,453	'	-21,384
Finite-lived intangible assets, net carrying amount	24,507	'	24,507	'	22,976
Intangible amortization expense	2,109	660	4,069	1,064	'
Future estimated amortization costs of intangible assets:	'	'	'	'	'
2014, remainder	4,494	'	4,494	'	'
2015	8,220	'	8,220	'	'
2016	5,887	'	5,887	'	'
2017	2,742	'	2,742	'	'
2018	2,295	'	2,295	'	'
Thereafter	869	'	869	'	'
Finite-lived intangible assets, net carrying amount	24,507	'	24,507	'	22,976
Developed technology rights [Member]	'	'	'	'	'
Intangible assets excluding goodwill:	'	'	'	'	'
Finite-lived intangible assets, gross carrying amount	34,968	'	34,968	'	29,468
Finite-lived intangible assets, accumulated amortization	-19,185	'	-19,185	'	-17,383
Finite-lived intangible assets, net carrying amount	15,783	'	15,783	'	12,085
Future estimated amortization costs of intangible assets:	'	'	'	'	'
Finite-lived intangible assets, net carrying amount	15,783	'	15,783	'	12,085
Customer relationships [Member]	'	'	'	'	'
Intangible assets excluding goodwill:	'	'	'	'	'
Finite-lived intangible assets, gross carrying amount	13,382	'	13,382	'	13,282
Finite-lived intangible assets, accumulated amortization	-5,767	'	-5,767	'	-3,726
Finite-lived intangible assets, net carrying amount	7,615	'	7,615	'	9,556
Future estimated amortization costs of intangible assets:	'	'	'	'	'
Finite-lived intangible assets, net carrying amount	7,615	'	7,615	'	9,556
Noncompete agreements [Member]	'	'	'	'	'
Intangible assets excluding goodwill:	'	'	'	'	'
Finite-lived intangible assets, gross carrying amount	804	'	804	'	804
Finite-lived intangible assets, accumulated amortization	-316	'	-316	'	-170
Finite-lived intangible assets, net carrying amount	488	'	488	'	634
Future estimated amortization costs of intangible assets:	'	'	'	'	'
Finite-lived intangible assets, net carrying amount	488	'	488	'	634
Trademarks and patents [Member]	'	'	'	'	'
Intangible assets excluding goodwill:	'	'	'	'	'
Finite-lived intangible assets, gross carrying amount	806	'	806	'	806
Finite-lived intangible assets, accumulated amortization	-185	'	-185	'	-105
Finite-lived intangible assets, net carrying amount	621	'	621	'	701
Future estimated amortization costs of intangible assets:	'	'	'	'	'
Finite-lived intangible assets, net carrying amount	$621	'	$621	'	$701

Fair_Value_Measurements_and_In2

Fair Value Measurements and Investments - Fair Value Measurements (Details) (USD $)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Fair value measurements and investments	'	'
Cash and cash equivalents, fair value disclosures	$226,845	$243,786
Short-term investments, fair value disclosures	0	8,015
Fair value, measurement with unobservable inputs reconciliations, recurring basis, liability value	250	495
Fair Value, measurement with unobservable inputs reconciliation, recurring basis, liability, settlements	-250	'
Fair value, measurement with unobservable inputs reconciliation, recurring basis, liability, gain (loss) included in earnings, description	5	'
Estimate of fair value (balance) [Member]	'	'
Fair value measurements and investments	'	'
Assets, fair value disclosure	'	223,109
Liabilities arising from contingencies, amount recognized	250	495
Quoted prices in active markets for identical assets (Level 1) [Member]	'	'
Fair value measurements and investments	'	'
Assets, fair value disclosure	'	215,094
Significant other observable inputs (Level 2) [Member]	'	'
Fair value measurements and investments	'	'
Assets, fair value disclosure	'	8,015
Convertible debt, fair value disclosures	24,129	'
Unobservable inputs (Level 3) [Member]	'	'
Fair value measurements and investments	'	'
Liabilities arising from contingencies, amount recognized	250	495
Money market funds [Member]	'	'
Fair value measurements and investments	'	'
Cash and cash equivalents, fair value disclosures	198,571	215,094
Money market funds [Member] | Estimate of fair value (balance) [Member]	'	'
Fair value measurements and investments	'	'
Cash and cash equivalents, fair value disclosures	198,571	215,094
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	198,571	215,094
Corporate debt securities [Member]	'	'
Fair value measurements and investments	'	'
Short-term investments, fair value disclosures	'	6,015
Corporate debt securities [Member] | Estimate of fair value (balance) [Member]	'	'
Fair value measurements and investments	'	'
Short-term investments, fair value disclosures	'	6,015
Corporate debt securities [Member] | Significant other observable inputs (Level 2) [Member]	'	'
Fair value measurements and investments	'	'
Short-term investments, fair value disclosures	'	6,015
Certificates of deposit [Member]	'	'
Fair value measurements and investments	'	'
Short-term investments, fair value disclosures	'	2,000
Certificates of deposit [Member] | Estimate of fair value (balance) [Member]	'	'
Fair value measurements and investments	'	'
Short-term investments, fair value disclosures	'	2,000
Certificates of deposit [Member] | Significant other observable inputs (Level 2) [Member]	'	'
Fair value measurements and investments	'	'
Short-term investments, fair value disclosures	'	$2,000

Fair_Value_Measurements_and_In3

Fair Value Measurements and Investments Fair Value Measurements and Investments - Investments (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of cash and cash equivalents, and investments	'	'
Cash and cash equivalents, fair value disclosures	$226,845	$243,786
Short-term investments, fair value disclosures	0	8,015
Cash [Member]	'	'
Schedule of cash and cash equivalents, and investments	'	'
Cash and cash equivalents, fair value disclosures	28,274	28,692
Money market funds [Member]	'	'
Schedule of cash and cash equivalents, and investments	'	'
Cash and cash equivalents, fair value disclosures	198,571	215,094
Corporate debt securities [Member]	'	'
Schedule of cash and cash equivalents, and investments	'	'
Short-term investments, fair value disclosures	'	6,015
Certificates of deposit [Member]	'	'
Schedule of cash and cash equivalents, and investments	'	'
Short-term investments, fair value disclosures	'	$2,000

Commitments_and_Contingencies_2

Commitments and Contingencies (Details) (USD $)	0 Months Ended	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Apr. 15, 2014	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Jul. 31, 2012
						Capital Lease Obligations [Member]
Debt instrument	'	'	'	'	'	'
Operating lease rent expense	'	$860	$403	$1,398	$803	'
Interest rate, stated percentage	'	'	'	'	'	4.50%
Operating lease obligations	'	'	'	'	'	'
2014, remainder	'	2,000	'	2,000	'	'
2015	'	4,622	'	4,622	'	'
2016	'	3,822	'	3,822	'	'
2017	'	2,965	'	2,965	'	'
2018	'	2,822	'	2,822	'	'
Thereafter	'	3,152	'	3,152	'	'
Total minimum operating lease payments	'	19,383	'	19,383	'	'
Future annual minimum lease payments under noncancelable operating and capital leases	'	'	'	'	'	'
2014, remainder	'	9	'	9	'	'
2015	'	11	'	11	'	'
Total minimum capital lease payments	'	20	'	20	'	'
Less: Amount representing interest	'	-1	'	-1	'	'
Present value of capital lease obligations	'	19	'	19	'	'
Less: Current portion	'	-17	'	-17	'	'
Long-term portion of capital lease obligations	'	2	'	2	'	'
Damages sought, value	$13,500	'	'	'	'	'

Convertible_Senior_Notes_Detai

Convertible Senior Notes (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013	Dec. 11, 2013	Jun. 30, 2014	Jun. 30, 2014
In Thousands, except Per Share data, unless otherwise specified			Convertible debt [Member]	Convertible debt [Member]	Convertible debt [Member]
Debt instrument	'	'	'	'	'
Face amount initial	'	'	$175,000	'	'
Face amount optional	'	'	26,250	'	'
Debt issuance cost	'	'	5,803	'	'
Proceeds from convertible debt	'	'	195,446	'	'
Interest rate, stated percentage	'	'	1.25%	'	'
Conversion ratio, initial (in shares)	'	'	25.6271	'	'
Number of shares convertible, initial rate (in shares)	'	'	5,158	'	'
Conversion price per share, initial (USD per share)	'	'	$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	'	'
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	157,218	152,928	156,672	157,218	157,218
Carrying amount of equity component	'	'	44,578	'	'
Debt instrument, face amount	'	'	'	201,250	201,250
Debt discount, net of amortization	'	'	'	44,032	44,032
Carrying amount of the equity component net	'	'	43,293	'	'
Issuance costs allocated to equity portion	'	'	1,285	'	'
Interest expense, 1.25% coupon	'	'	'	624	1,253
Amortization of debt discount	'	'	'	2,160	4,291
Amortization of debt issuance costs	'	'	'	13	25
Interest expense, total	'	'	'	$2,797	$5,569

Debt_Details

Debt (Details) (Loans Payable [Member], USD $)	0 Months Ended	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Apr. 30, 2011	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Debt instrument	'	'	'	'	'
Interest rate at period end	'	4.50%	'	4.50%	'
Duration until repayment date after a loan amount is drawn	'48 months	'	'	'	'
Interest expense	'	$23	$38	$51	$80
Repayment commitments	'	'	'	'	'
2014, remainder	'	821	'	821	'
2015	'	684	'	684	'
Carrying amount of long-term debt	$6,000	$1,505	'	$1,505	'
Interest rate in excess of prime rate	'	'	'	'	'
Debt instrument	'	'	'	'	'
Basis spread on variable rate	0.50%	'	'	'	'

Common_Stock_Details

Common Stock (Details) (USD $)	Jun. 30, 2014	Dec. 31, 2013
In Thousands, except Per Share data, unless otherwise specified	class
Stockholders' equity:	'	'
Number of classes of stock the Company is authorized to issue (in classes of stock)	2	'
Total shares authorized (in shares)	205,000	'
Preferred stock authorized (in shares)	5,000	'
Common stock authorized (in shares)	200,000	200,000
Par value of common stock (USD per share)	$0.00	$0.00
Par value of preferred stock (USD per share)	$0.00	'
Common stock outstanding (in shares)	37,299	36,140
Number of shares of common stock reserved for future issuance	'	'
Total shares reserved	19,939	18,940
Convertible debt [Member]	'	'
Number of shares of common stock reserved for future issuance	'	'
Common stock issuable upon conversion of convertible senior notes (in shares)	5,158	5,158
ESPP 2012 Plan [Member]	'	'
Number of shares of common stock reserved for future issuance	'	'
Shares available for future grant under the stock plans (in shares)	1,026	759
2012 Equity Incentive Plan [Member]	'	'
Number of shares of common stock reserved for future issuance	'	'
Shares available for future grant under the stock plans (in shares)	5,037	4,584
2012 Equity Incentive Plan [Member] | Restricted stock units (RSUs) [Member]	'	'
Number of shares of common stock reserved for future issuance	'	'
Common stock issuable upon settlement of outstanding restricted stock units (in shares)	2,236	1,216
2012 Equity Incentive Plan [Member] | Employee stock option [Member]	'	'
Number of shares of common stock reserved for future issuance	'	'
Options outstanding under stock option plans (in shares)	6,482	7,223

Stock_Equity_Plans_StockBased_

Stock Equity Plans - Stock-Based Compensation Plans (Details)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Stock-based compensation:	'	'
Equity incentive plans held by the company (number of plans)	2	'
2012 Equity Incentive Plan [Member]	'	'
Stock-based compensation:	'	'
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	'
Shares available for future grant under the stock plans (in shares)	5,037	4,584
2012 Equity Incentive Plan [Member] | Employee stock option [Member] | Minimum [Member]	'	'
Stock-based compensation:	'	'
Award vesting period	'3 years	'
2012 Equity Incentive Plan [Member] | Employee stock option [Member] | Maximum [Member]	'	'
Stock-based compensation:	'	'
Term until award expiration	'10 years	'
Award vesting period	'4 years	'
2012 Equity Incentive Plan [Member] | Restricted stock units (RSUs) [Member]	'	'
Stock-based compensation:	'	'
Award vesting period	'4 years	'

Stock_Equity_Plans_Stock_Optio

Stock Equity Plans - Stock Option Activity (Details) (2012 Equity Incentive Plan [Member], Employee stock option [Member], USD $)	3 Months Ended		6 Months Ended		12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Stock-based compensation:	'	'	'	'	'
Options, grants in period, weighted average grant date fair value (USD per share)	$19.51	$10.58	$19.88	$8.19	'
Stock option activity under the Plan	'	'	'	'	'
Outstanding, beginning of period (in shares)	'	'	7,223	'	'
Options, grants in period, gross (in shares)	'	'	500	'	'
Options, exercises in period (in shares)	'	'	-1,029	'	'
Options, forfeitures and expirations in period (in shares)	'	'	-212	'	'
Outstanding, ending of period (in shares)	6,482	'	6,482	'	7,223
Stock option activity under the Plan, in weighted average exercise price:	'	'	'	'	'
Balance at beginning of period (USD per share)	'	'	$8.17	'	'
Options, grants in period (USD per share)	'	'	$36.06	'	'
Options, exercises in period (USD per share)	'	'	$6.28	'	'
Options, forfeitures and expirations in period (USD per share)	'	'	$15.19	'	'
Balance at ending of period (USD per share)	$10.40	'	$10.40	'	$8.17
Weighted average remaining contractual term	'	'	'6 years 8 months 1 day	'	'6 years 9 months 25 days
Options, outstanding, intrinsic value	$175,472	'	$175,472	'	$180,543
Options, exercises in period, intrinsic value	'	'	32,192	24,063	'
Proceeds from stock options exercised	'	'	6,465	8,543	'
Options, vested in period, fair value	2,909	1,565	5,870	3,768	'
Unamortized stock-based compensation expense	$19,481	'	$19,481	'	'
Average remaining vesting term	'	'	'2 years 3 months 11 days	'	'
Maximum [Member]	'	'	'	'	'
Fair value assumptions	'	'	'	'	'
Expected life	'6 years 29 days	'5 years 10 months 24 days	'6 years 29 days	'5 years 10 months 24 days	'
Weighted average volatility rate	58.00%	58.00%	58.00%	58.00%	'
Risk free interest rate	1.90%	1.10%	1.90%	1.10%	'
Expected dividend rate	0.00%	0.00%	0.00%	0.00%	'
Minimum [Member]	'	'	'	'	'
Fair value assumptions	'	'	'	'	'
Expected life	'5 years 3 months 22 days	'5 years 10 months 24 days	'5 years 3 months 22 days	'5 years 10 months 24 days	'
Weighted average volatility rate	54.00%	58.00%	54.00%	58.00%	'
Risk free interest rate	1.80%	1.10%	1.80%	1.10%	'
Expected dividend rate	0.00%	0.00%	0.00%	0.00%	'

Stock_Equity_Plans_Restricted_

Stock Equity Plans - Restricted Stock Units (Details) (Restricted stock units (RSUs) [Member], 2012 Equity Incentive Plan [Member], USD $)	6 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jun. 30, 2014
Restricted stock units (RSUs) [Member] | 2012 Equity Incentive Plan [Member]	'
RSU's outstanding, number of shares:	'
Awarded at beginning of period (in shares)	1,214
Awards granted (in shares)	1,155
Awards vested (in shares)	-55
Awards forfeited (in shares)	-78
Awarded at end of period (in shares)	2,236
RSUs outstanding, granted fair value per unit	'
Awarded at beginning of period (USD per share)	$29.57
Awards granted (USD per share)	$34.49
Awards vested (USD per share)	$37.48
Awards forfeited (USD per share)	$29.66
Awarded at end of period (USD per share)	$32.01
Unamortized stock-based compensation expense	$47,888
Average remaining vesting term	'3 years 5 months 1 day

Stock_Equity_Plans_Employee_St

Stock Equity Plans - Employee Stock Purchase Plan (Details) (ESPP 2012 Plan [Member], USD $)	0 Months Ended	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Mar. 30, 2012	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
ESPP 2012 Plan [Member]	'	'	'	'	'	'
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	'	'	'	'	'
Shares available for future grant under the stock plans (in shares)	'	1,026	'	1,026	'	759
Expected life	'	'6 months	'6 months	'6 months	'6 months	'
Weighted average volatility rate	'	52.00%	40.00%	52.00%	40.00%	'
Risk free interest rate	'	0.10%	0.10%	0.10%	0.10%	'
Expected dividend rate	'	0.00%	0.00%	0.00%	0.00%	'
Unamortized stock-based compensation expense	'	$670	'	$670	'	'
Average remaining vesting term	'	'	'	'4 months 15 days	'	'

Net_Loss_per_Share_Details

Net Loss per Share (Details)	6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013
Antidilutive securities excluded from computation of earnings per share	'	'
Total antidilutive securities excluded from computation of earnings per share (in shares)	13,982	8,391
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)	6,482	8,248
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)	106	102
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)	0	2
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)	2,236	39
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	0

Segment_Reporting_Revenue_by_S

Segment Reporting - Revenue by Solution (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
			segment
Revenue by Solution [Abstract]	'	'	'	'
Number of operating and reportable segments	'	'	1	'
Revenue from external customers	'	'	'	'
Revenue	$46,398	$31,827	$89,102	$62,591
Privacy, protection and security [Member]	'	'	'	'
Revenue from external customers	'	'	'	'
Revenue	35,549	22,609	68,152	44,375
Archiving and governance [Member]	'	'	'	'
Revenue from external customers	'	'	'	'
Revenue	$10,849	$9,218	$20,950	$18,216

Segment_Reporting_by_Geographi

Segment Reporting - by Geographic Area (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Segment reporting:	'	'	'	'
Revenue	$46,398	$31,827	$89,102	$62,591
Total long-lived assets	15,337	11,221	15,337	11,221
United States [Member]	'	'	'	'
Segment reporting:	'	'	'	'
Revenue	38,012	26,288	73,229	51,797
Total long-lived assets	12,445	9,425	12,445	9,425
Rest of world [Member]	'	'	'	'
Segment reporting:	'	'	'	'
Revenue	8,386	5,539	15,873	10,794
Total long-lived assets	$2,892	$1,796	$2,892	$1,796

Income_Taxes_Details

Income Taxes (Details) (USD $)	3 Months Ended		6 Months Ended
In Thousands, unless otherwise specified	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Valuation allowance	'	'	'	'
Income tax expense (benefit)	$147	($3,347)	$291	($3,205)
Loss before (provision for) benefit from income taxes	14,978	5,412	29,229	11,663
Effective income tax rate	'	'	1.00%	27.50%
Valuation allowance, deferred tax asset, change in amount	'	'	'	3,392
Unrecognized tax benefits	3,942	'	3,942	'
Accrued interest and penalties	239	'	239	'
Uncertain tax benefits that would affect effective tax rate if recognized	1,517	'	1,517	'
Increase in gross uncertain tax benefits	84	'	'	'
Increase for tax positions taken in the current period	75	'	'	'
Increase for tax positions taken in prior periods	30	'	'	'
Decrease for tax positions from statue of expiration	$21	'	'	'