0001262039-15-000016 | 10-Q | XBRL Viewer

Commitments and Contingencies (Tables)

3 Months Ended

Mar. 31, 2015

Commitments and Contingencies Disclosure [Abstract]

Contractual Obligation, Fiscal Year Maturity Schedule [Table Text Block]

The following table summarizes our future principal contractual obligations as of March 31, 2015 (in thousands):



	Total		2015 (remainder)		2016		2017		2018		2019		Thereafter
Operating lease commitments	$	40,130	$	9,560	$	9,453	$	7,252	$	6,506	$	4,567	$	2,792
Less: Sublease rental income	224		224		—		—		—		—		—
Operating lease commitments—net	39,906		9,336		9,453		7,252		6,506		4,567		2,792
Inventory purchase commitments	67,715		67,715		—		—		—		—		—
Other contractual commitments and open purchase orders	28,108		26,020		1,518		570		—		—		—
Total	$	135,729	$	103,071	$	10,971	$	7,822	$	6,506	$	4,567	$	2,792

Schedule of Product Warranty Liability [Table Text Block]

Accrued warranty activities are summarized as follows (in thousands):



	Three Months Ended
	March 31, 2015			March 31, 2014
Accrued warranty balance—beginning of the period	$	4,269		$	3,037
Warranty costs incurred	(1,095		)	(756		)
Provision for warranty for the period	945			837
Adjustment related to pre-existing warranties	222			(313		)
Accrued warranty balance—end of the period	$	4,341		$	2,805

Investments in Privately-Held Companies	3 Months Ended
Investments in Privately-Held Companies	Mar. 31, 2015
Investments, All Other Investments [Abstract]
INVESTMENTS IN PRIVATELY-HELD COMPANIES	INVESTMENTS IN PRIVATELY-HELD COMPANIES As of March 31, 2015, we have invested a total of $6.4 million in the equity securities of three privately-held companies. Each of these investments are accounted for as cost-basis investments, as we own less than 20% of the voting securities and do not have the ability to exercise significant influence over operating and financial policies of the respective entities. These investments are carried at historical cost and are recorded as Other assets on our condensed consolidated balance sheets and would be measured at fair value if indicators of impairment exist. During the three months ended March 31, 2015, no events have occurred that would adversely affect the carrying value of these investments.

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2015	Apr. 24, 2015
Document Information [Line Items]
Entity Registrant Name	FORTINET INC
Entity Central Index Key	0001262039
Document Type	10-Q
Document Period End Date	Mar. 31, 2015
Amendment Flag	false
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		169,563,012

Commitments and Contingencies Other Contractual Commitments and Open Purchase Orders (Details) $ in Thousands	Mar. 31, 2015 USD ($)
Operating lease commitments:
Operating leases commitments, 2015 (remainder)	$ 9,560
Operating lease commitments, 2016	9,453
Operating lease commitments, 2017	7,252
Operating lease commitments, 2018	6,506
Operating lease commitments, 2019	4,567
Operating lease commitments, Thereafter	2,792
Operating lease commitments	40,130
Sublease rental income:
Sublease rental income, 2015 (remainder)	224
Sublease rental income, 2016	0
Sublease rental income, 2017	0
Sublease rental income, 2018	0
Sublease rental income, 2019	0
Sublease rental income, Thereafter	0
Sublease rental income	224
Operating lease commitments - net:
Operating lease commitments - net, 2015 (remainder)	9,336
Operating lease commitments - net, 2016	9,453
Operating lease commitments - net, 2017	7,252
Operating lease commitments - net, 2018	6,506
Operating lease commitments - net, 2019	4,567
Operating lease commitments - net, Thereafter	2,792
Operating lease commitments - net	39,906
Inventory purchase commitments:
Inventory purchase commitments, 2015 (remainder)	67,715
Inventory purchase commitments, 2016	0
Inventory purchase commitments, 2017	0
Inventory purchase commitments, 2018	0
Inventory purchase commitments, 2019	0
Inventory purchase commitments, Thereafter	0
Inventory purchase commitments	67,715
Other contractual commitments and open purchase orders:
Other contractual commitments and open purchase orders, 2015 (remainder)	26,020
Other contractual commitments and open purchase orders, 2016	1,518
Other contractual commitments and open purchase orders, 2017	570
Other contractual commitments and open purchase orders, 2018	0
Other contractual commitments and open purchase orders, 2019	0
Other contractual commitments and open purchase orders, Thereafter	0
Other contractual commitments and open purchase orders	28,108
Contractual Obligation	135,729
Contractual Obligation, 2015 (remainder)	103,071
Contractual Obligation, 2016	10,971
Contractual Obligation, 2017	7,822
Contractual Obligation, 2018	6,506
Contractual Obligation, 2019	4,567
Contractual Obligation, Thereafter	$ 2,792

Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Rent expense	$ 3,100	$ 2,700
Open purchase orders	67,715
Other contract commitments and open purchase orders	$ 28,108

Deferred Revenue

3 Months Ended

Mar. 31, 2015

Deferred Revenue Disclosure [Abstract]

DEFERRED REVENUE

Deferred revenue consisted of the following as of March 31, 2015 and December 31, 2014 (in thousands):



	March 31, 2015		December 31, 2014
Product	$	4,255	$	4,642
Service	595,916		554,115
Total deferred revenue	$	600,171	$	558,757
Reported As:
Current	$	406,526	$	368,929
Non-current	193,645		189,828
Total deferred revenue	$	600,171	$	558,757

Income Taxes	3 Months Ended
Income Taxes	Mar. 31, 2015
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES The effective tax rate was 5% for the three months ended March 31, 2015, compared to an effective tax rate of 39% for the same period last year. The provision for income taxes for the periods presented is comprised of U.S. federal and state taxes, Singapore and other foreign income taxes, withholding tax, and transfer pricing allocations which impact jurisdictional income taxed at various tax rates. During the three months ended March 31, 2015, discrete items included a higher tax benefit from stock-based compensation expense and foreign exchange impact relating to uncertain tax benefit for developments in international tax that impacted the quarterly effective tax rate. As of March 31, 2015 and December 31, 2014, unrecognized tax benefits were $46.6 million and $44.2 million, respectively. The total amount of $46.6 million in unrecognized tax benefits, if recognized, would favorably impact the effective tax rate. It is our policy to classify accrued interest and penalties related to unrecognized tax benefits in the provision for income taxes. As of March 31, 2015, we had accrued approximately $4.5 million for estimated interest related to uncertain tax positions. We file income tax returns in the U.S. federal jurisdiction, and various U.S. state and foreign jurisdictions. The statute of limitations is open for years that generated state net operating loss carryforwards and after 2009 for state jurisdictions. Additionally, we have foreign net operating losses that have an indefinite life. Generally, we are no longer subject to non-U.S. income tax examinations by tax authorities for tax years prior to 2008. We are no longer subject to examination by U.S federal income tax authorities for tax years prior to 2010.

Property and Equipment—Net

3 Months Ended

Mar. 31, 2015

Property, Plant and Equipment [Abstract]

PROPERTY AND EQUIPMENT—Net

Property and equipment—net consisted of the following as of March 31, 2015 and December 31, 2014 (in thousands):



	March 31, 2015			December 31, 2014
Land	$	13,895		$	13,895
Building and building improvements	20,224			20,166
Evaluation units	34,053			31,474
Computer equipment and software	38,306			31,821
Furniture and fixtures	5,469			5,096
Construction-in-progress	3,157			3,902
Leasehold improvements	8,711			7,998
Total property and equipment	123,815			114,352
Less: accumulated depreciation	(60,328		)	(55,433		)
Property and equipment—net	$	63,487		$	58,919

Depreciation expense was $6.0 million and $3.9 million during the three months ended March 31, 2015 and March 31, 2014, respectively.

Financial Instruments and Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2015

Financial Instruments and Fair Value [Abstract]

Summary of Investments [Table Text Block]

The following table summarizes our investments as of March 31, 2015 and December 31, 2014 (in thousands):



	March 31, 2015
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Corporate debt securities	$	568,456	$	593	$	(243	)	$	568,806
Commercial paper	43,758		1		(9		)	43,750
Municipal bonds	49,825		21		(26		)	49,820
Certificates of deposit and term deposits ⁽¹⁾	13,080		—		—			13,080
U.S. government and agency securities	10,749		8		—			10,757
Total available-for-sale securities	$	685,868	$	623	$	(278	)	$	686,213



	December 31, 2014
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Corporate debt securities	$	589,526	$	365	$	(875	)	$	589,016
Commercial paper	51,156		3		(4		)	51,155
Municipal bonds	39,745		15		(39		)	39,721
Certificates of deposit and term deposits ⁽¹⁾	22,854		—		—			22,854
U.S. government and agency securities	5,749		1		(6		)	5,744
Total available-for-sale securities	$	709,030	$	384	$	(924	)	$	708,490

⁽¹⁾ The majority of our certificates of deposit and term deposits are foreign deposits.

Schedule of Unrealized Loss on Investments [Table Text Block]

The following table shows the gross unrealized losses and the related fair values of our investments that have been in a continuous unrealized loss position as of March 31, 2015 and December 31, 2014 (in thousands):



	March 31, 2015
	Less Than 12 Months					12 Months or Greater					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
Corporate debt securities	$	177,364	$	(214	)	$	13,142	$	(29	)	$	190,506	$	(243	)
Commercial paper	8,375		(9		)	—		—			8,375		(9		)
Municipal bonds	32,205		(26		)	—		—			32,205		(26		)
Total available-for-sale securities	$	217,944	$	(249	)	$	13,142	$	(29	)	$	231,086	$	(278	)



	December 31, 2014
	Less Than 12 Months					12 Months or Greater					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
Corporate debt securities	$	317,011	$	(858	)	$	6,011	$	(17	)	$	323,022	$	(875	)
Commercial paper	8,185		(4		)	—		—			8,185		(4		)
Municipal bonds	26,684		(39		)	—		—			26,684		(39		)
U.S. government and agency securities	4,745		(6		)	—		—			4,745		(6		)
Total available-for-sale securities	$	356,625	$	(907	)	$	6,011	$	(17	)	$	362,636	$	(924	)

Investments Classified by Contractual Maturity Date [Table Text Block]

The contractual maturities of our investments as of March 31, 2015 and December 31, 2014 were as follows (in thousands):



	March 31, 2015		December 31, 2014
Due within one year	$	417,605	$	436,766
Due within one to three years	268,608		271,724
Total	$	686,213	$	708,490

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

The following table presents the fair value of our financial assets and liabilities measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014 (in thousands):



	March 31, 2015						December 31, 2014
	Aggregate Fair Value		Quoted Prices in Active Markets For Identical Assets		Significant Other Observable Remaining Inputs		Aggregate Fair Value		Quoted Prices in Active Markets For Identical Assets		Significant Other Observable Remaining Inputs
			(Level 1)		(Level 2)				(Level 1)		(Level 2)
Assets:
Corporate debt securities	$	568,806	$	—	$	568,806	$	589,016	$	—	$	589,016
Commercial paper	43,750		—		43,750		51,155		—		51,155
Municipal bonds	49,820		—		49,820		39,721		—		39,721
Certificates of deposit and term deposits	13,080		—		13,080		22,854		—		22,854
Money market funds	29,154		29,154		—		13,311		13,311		—
U.S. government and agency securities	10,757		2,001		8,756		5,744		1,998		3,746
Total	$	715,367	$	31,155	$	684,212	$	721,801	$	15,309	$	706,492

Reported as:
Cash equivalents	$	29,154					$	13,311
Short-term investments	417,605						436,766
Long-term investments	268,608						271,724
Total	$	715,367					$	721,801

Accumulated Other Comprehensive Income (Loss) (Reclassification Out of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
OTHER EXPENSE—Net	$ (677)	$ (389)
Provision for income taxes	(83)	(5,366)
Net income	1,560	$ 8,393
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Provision for income taxes	1
Net income	(3)
Unrealized gains on investments [Member] \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
OTHER EXPENSE—Net	$ (4)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Net Income Per Share , Anti Dilutive Securities (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	1,751	6,785
Stock options [Member] \| Stock Compensation Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	249	5,079
RSUs (including PSUs) [Member] \| Stock Compensation Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	1,333	1,348
ESPP [Member] \| Stock Compensation Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	169	358

Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 1,560	$ 8,393
Other comprehensive income (loss)—net of taxes:
Foreign currency translation losses	0	(1,017)
Unrealized gains on investments	885	2
Tax provision related to items of other comprehensive income	(310)	0
Other comprehensive income (loss)—net of taxes	575	(1,015)
Comprehensive income	$ 2,135	$ 7,378

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Foreign Currency Derivatives (Tables)

3 Months Ended

Mar. 31, 2015

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]

The notional amount of forward exchange contracts to hedge balance sheet accounts were (in thousands):



	Buy/Sell	Notional
Currency—As of March 31, 2015
CAD	Sell	$	9,093

Currency—As of December 31, 2014
CAD	Buy	$	6,879

Deferred Revenue (Details) - USD ($) $ in Thousands	Mar. 31, 2015	Dec. 31, 2014
Deferred Revenue Arrangement [Line Items]
Short-term	$ 406,526	$ 368,929
Long-term	193,645	189,828
Total deferred revenue	600,171	558,757
Product [Member]
Deferred Revenue Arrangement [Line Items]
Total deferred revenue	4,255	4,642
Service [Member]
Deferred Revenue Arrangement [Line Items]
Total deferred revenue	$ 595,916	$ 554,115

Stockholders' Equity , Allocation of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 18,922	$ 12,930
Income tax benefit from employee stock option plans	3,377	3,349
Cost of product revenue [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	140	113
Cost of services revenue [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	1,632	1,329
Research and development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	5,157	3,882
Sales and marketing [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	9,307	5,746
General and administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	2,686	1,860
Stock options [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	3,455	4,692
RSUs (including PSUs) [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	14,292	7,363
ESPP [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 1,175	$ 875

Financial Instruments and Fair Value Measurements

3 Months Ended

Mar. 31, 2015

Financial Instruments and Fair Value [Abstract]

FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS

The following table summarizes our investments as of March 31, 2015 and December 31, 2014 (in thousands):



	March 31, 2015
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Corporate debt securities	$	568,456	$	593	$	(243	)	$	568,806
Commercial paper	43,758		1		(9		)	43,750
Municipal bonds	49,825		21		(26		)	49,820
Certificates of deposit and term deposits ⁽¹⁾	13,080		—		—			13,080
U.S. government and agency securities	10,749		8		—			10,757
Total available-for-sale securities	$	685,868	$	623	$	(278	)	$	686,213



	December 31, 2014
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Corporate debt securities	$	589,526	$	365	$	(875	)	$	589,016
Commercial paper	51,156		3		(4		)	51,155
Municipal bonds	39,745		15		(39		)	39,721
Certificates of deposit and term deposits ⁽¹⁾	22,854		—		—			22,854
U.S. government and agency securities	5,749		1		(6		)	5,744
Total available-for-sale securities	$	709,030	$	384	$	(924	)	$	708,490

⁽¹⁾ The majority of our certificates of deposit and term deposits are foreign deposits.



	March 31, 2015
	Less Than 12 Months					12 Months or Greater					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
Corporate debt securities	$	177,364	$	(214	)	$	13,142	$	(29	)	$	190,506	$	(243	)
Commercial paper	8,375		(9		)	—		—			8,375		(9		)
Municipal bonds	32,205		(26		)	—		—			32,205		(26		)
Total available-for-sale securities	$	217,944	$	(249	)	$	13,142	$	(29	)	$	231,086	$	(278	)



	December 31, 2014
	Less Than 12 Months					12 Months or Greater					Total
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
Corporate debt securities	$	317,011	$	(858	)	$	6,011	$	(17	)	$	323,022	$	(875	)
Commercial paper	8,185		(4		)	—		—			8,185		(4		)
Municipal bonds	26,684		(39		)	—		—			26,684		(39		)
U.S. government and agency securities	4,745		(6		)	—		—			4,745		(6		)
Total available-for-sale securities	$	356,625	$	(907	)	$	6,011	$	(17	)	$	362,636	$	(924	)

The contractual maturities of our investments as of March 31, 2015 and December 31, 2014 were as follows (in thousands):



	March 31, 2015		December 31, 2014
Due within one year	$	417,605	$	436,766
Due within one to three years	268,608		271,724
Total	$	686,213	$	708,490

Available-for-sale securities are reported at fair value, with unrealized gains and losses, net of tax, included as a separate component of stockholders’ equity and in total comprehensive income. Realized gains and losses on available-for-sale securities are included in Other expense—net in our condensed consolidated statements of operations. Realized gains and losses from the sale of available-for-sale securities were not significant in any period presented.

The unrealized losses on our available-for-sale securities were caused by fluctuations in market value and interest rates as a result of the economic environment. As the decline in market value is attributable to changes in market conditions and not credit quality, and because we have concluded currently that we neither intend to sell nor is it more likely than not that we will be required to sell these investments prior to a recovery of par value, we do not consider these investments to be other-than temporarily impaired as of March 31, 2015.

Fair Value Accounting—We apply the following fair value hierarchy for disclosure of the inputs used to measure fair value. This hierarchy prioritizes the inputs into three broad levels as follows:

Level 1—Inputs are unadjusted quoted prices in active markets for identical assets or liabilities.

Level 2—Inputs are quoted prices for similar assets and liabilities in active markets or inputs that are observable for the assets or liabilities, either directly or indirectly through market corroboration, for substantially the full term of the financial instruments.

Level 3—Unobservable inputs based on our own assumptions used to measure assets and liabilities at fair value. The inputs require significant management judgment or estimation.

We measure the fair value of money market funds and certain U.S. government and agency securities using quoted prices in active markets for identical assets. The fair value of all other financial instruments was based on quoted prices for similar assets in active markets, or model driven valuations using significant inputs derived from or corroborated by observable market data.

We classify investments within Level 1 if quoted prices are available in active markets for identical securities.

We classify items within Level 2 if the investments are valued using model driven valuations using observable inputs such as quoted market prices, benchmark yields, reported trades, broker/dealer quotes or alternative pricing sources with reasonable levels of price transparency. Investments are held by custodians who obtain investment prices from a third-party pricing provider that incorporates standard inputs in various asset price models.

Fair Value of Financial Instruments

Assets and Liabilities Measured at Fair Value on a Recurring Basis

The following table presents the fair value of our financial assets and liabilities measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014 (in thousands):



	March 31, 2015						December 31, 2014
	Aggregate Fair Value		Quoted Prices in Active Markets For Identical Assets		Significant Other Observable Remaining Inputs		Aggregate Fair Value		Quoted Prices in Active Markets For Identical Assets		Significant Other Observable Remaining Inputs
			(Level 1)		(Level 2)				(Level 1)		(Level 2)
Assets:
Corporate debt securities	$	568,806	$	—	$	568,806	$	589,016	$	—	$	589,016
Commercial paper	43,750		—		43,750		51,155		—		51,155
Municipal bonds	49,820		—		49,820		39,721		—		39,721
Certificates of deposit and term deposits	13,080		—		13,080		22,854		—		22,854
Money market funds	29,154		29,154		—		13,311		13,311		—
U.S. government and agency securities	10,757		2,001		8,756		5,744		1,998		3,746
Total	$	715,367	$	31,155	$	684,212	$	721,801	$	15,309	$	706,492

Reported as:
Cash equivalents	$	29,154					$	13,311
Short-term investments	417,605						436,766
Long-term investments	268,608						271,724
Total	$	715,367					$	721,801

There were no transfers between Level 1 and Level 2 of the fair value hierarchy during the period ended March 31, 2015.

Accumulated Other Comprehensive Income (Loss) (Changes in Accumulated Balances of Other Comprehensive Income (Loss)) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2015 USD ($)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ (349)
Other comprehensive income before reclassifications	578
Amounts reclassified from accumulated other comprehensive income (loss)	(3)
Net current-period other comprehensive income	575
Ending balance	226
Tax Benefit (Provision) Related to Items of Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	191
Other comprehensive income before reclassifications	(311)
Amounts reclassified from accumulated other comprehensive income (loss)	1
Net current-period other comprehensive income	(310)
Ending balance	(119)
Unrealized Gains and Losses on Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(540)
Other comprehensive income before reclassifications	889
Amounts reclassified from accumulated other comprehensive income (loss)	(4)
Net current-period other comprehensive income	885
Ending balance	$ 345

Segment and Significant Customer Information

3 Months Ended

Mar. 31, 2015

Segment Reporting [Abstract]

SEGMENT AND SIGNIFICANT CUSTOMER INFORMATION

Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the chief operating decision maker in deciding how to allocate resources and in assessing performance. Our chief operating decision maker is our chief executive officer. Our chief executive officer reviews financial information presented on a consolidated basis, accompanied by information about revenue by geographic region for purposes of allocating resources and evaluating financial performance. We have one business activity, and there are no segment managers who are held accountable for operations, operating results and plans for levels or components below the consolidated unit level. Accordingly, we have determined that we have one operating segment, and therefore, one reportable segment.

Revenue by geographic region is based on the billing address of the customer. The following table sets forth revenue (in thousands):



	Three Months Ended
Revenue	March 31, 2015		March 31, 2014
Americas:
United States	$	58,501	$	44,793
Other Americas	33,059		27,639
Total Americas	91,560		72,432
Europe, Middle East, and Africa (“EMEA”)	75,664		56,643
Asia Pacific and Japan (“APAC”)	45,662		39,874
Total revenue	$	212,886	$	168,949

The following table sets forth property and equipment by geographic region as of March 31, 2015 and December 31, 2014 (in thousands):




Property and Equipment—net	March 31, 2015		December 31, 2014
Americas:
United States	$	49,471	$	46,116
Canada	6,356		6,054
Other Americas	924		875
Total Americas	56,751		53,045
EMEA	3,723		3,256
APAC	3,013		2,618
Total property and equipment—net	$	63,487	$	58,919

The following customers, each of which is a distributor, accounted for 10% or more of our revenue:



	Three Months Ended
	March 31, 2015		March 31, 2014
Exclusive Networks Group	17	%	14	%
Ingram Micro	—	%	10	%

The following customers, each of which is a distributor, accounted for 10% or more of net accounts receivable:



	March 31, 2015		December 31, 2014
Exclusive Networks Group	19	%	18	%
Fine Tec Computer	12	%	—	%

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8981-108599

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9038-108599

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8971-108599

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8595-108599

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8380-108599

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8933-108599

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 26
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8844-108599

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8984-108599

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 40
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9031-108599

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9054-108599

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8538-108599

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 29
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8864-108599

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8924-108599

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8906-108599

+ Details

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
REVENUE:
Product	$ 97,509	$ 76,765
Service	115,377	92,184
Total revenue	212,886	168,949
COST OF REVENUE:
Product	41,368	32,139
Service	22,234	18,604
Total cost of revenue	63,602	50,743
GROSS PROFIT:
Product	56,141	44,626
Service	93,143	73,580
Total gross profit	149,284	118,206
OPERATING EXPENSES:
Research and development	35,816	29,055
Sales and marketing	100,609	67,326
General and administrative	11,961	9,010
Total operating expenses	148,386	105,391
OPERATING INCOME	898	12,815
INTEREST INCOME	1,422	1,333
OTHER EXPENSE—Net	(677)	(389)
INCOME BEFORE INCOME TAXES	1,643	13,759
PROVISION FOR INCOME TAXES	83	5,366
NET INCOME	$ 1,560	$ 8,393
Net income per share (Note 6):
Basic (in dollars per share)	$ 0.01	$ 0.05
Diluted (in dollars per share)	$ 0.01	$ 0.05
Weighted-average shares outstanding:
Basic (in shares)	168,077	162,391
Diluted (in shares)	173,720	168,114

Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2015	Dec. 31, 2014
Inventory [Abstract]
Raw materials	$ 12,077	$ 10,617
Finished goods	59,983	58,860
Inventory	72,060	69,477
Finished goods held by distributors	1,000	1,200
Materials at contract manufacturers	$ 4,600	$ 4,800

Commitments and Contingencies

3 Months Ended

Mar. 31, 2015

Commitments and Contingencies Disclosure [Abstract]

COMMITMENTS AND CONTINGENCIES

The following table summarizes our future principal contractual obligations as of March 31, 2015 (in thousands):



	Total		2015 (remainder)		2016		2017		2018		2019		Thereafter
Operating lease commitments	$	40,130	$	9,560	$	9,453	$	7,252	$	6,506	$	4,567	$	2,792
Less: Sublease rental income	224		224		—		—		—		—		—
Operating lease commitments—net	39,906		9,336		9,453		7,252		6,506		4,567		2,792
Inventory purchase commitments	67,715		67,715		—		—		—		—		—
Other contractual commitments and open purchase orders	28,108		26,020		1,518		570		—		—		—
Total	$	135,729	$	103,071	$	10,971	$	7,822	$	6,506	$	4,567	$	2,792

Operating Leases—We lease certain facilities under various non-cancelable operating leases, which expire through 2024. In addition to the amounts above, certain leases require us to pay variable costs such as taxes, maintenance, insurance, and asset retirement obligations. The terms of certain operating leases also provide for renewal options and escalation clauses. Rent expense was $3.1 million and $2.7 million during the three months ended March 31, 2015 and 2014, respectively. Rent expense is recognized using the straight-line method over the term of the lease.

Contract Manufacturer and Other Commitments—Our independent contract manufacturers procure components and build our products based on our forecasts. These forecasts are based on estimates of future demand for our products, which are in turn based on historical trends and analysis, adjusted for overall market conditions. In order to reduce manufacturing lead times and plan for adequate component supply, we may issue purchase orders to some of our independent contract manufacturers which may not be cancelable. As of March 31, 2015, we had $67.7 million of open purchase orders with our independent contract manufacturers.

In addition to commitments with contract manufacturers, we have other contractual commitments and open purchase orders in the ordinary course of business for which we have not received goods or services. As of March 31, 2015, we had $28.1 million in other contractual commitments and open purchase orders.

Warranties—Accrued warranty activities are summarized as follows (in thousands):



	Three Months Ended
	March 31, 2015			March 31, 2014
Accrued warranty balance—beginning of the period	$	4,269		$	3,037
Warranty costs incurred	(1,095		)	(756		)
Provision for warranty for the period	945			837
Adjustment related to pre-existing warranties	222			(313		)
Accrued warranty balance—end of the period	$	4,341		$	2,805

Litigation—We are involved in disputes, litigation, and other legal actions. For lawsuits where we are the defendant, we are in the process of defending these litigation matters, and while there can be no assurances and the outcome of these matters is currently not determinable, we currently believe that there are no existing claims or proceedings that are likely to have a material adverse effect on our financial position. There are many uncertainties associated with any litigation and these actions or other third-party claims against us may cause us to incur costly litigation or substantial settlement charges. In addition, the resolution of any intellectual property litigation may require us to make royalty payments, which could adversely affect our gross margins in future periods. If any of those events were to occur, our business, financial condition, results of operations, and cash flows could be adversely affected. The actual liability in any such matters may be materially different from our estimates, if any, which could result in the need to adjust the liability and record additional expenses. We have not recorded any significant accrual for loss contingencies associated with such legal proceedings; determined that an unfavorable outcome is probable or reasonably possible; or determined that the amount or range of any possible loss is reasonably estimable.

Indemnification—Under the indemnification provisions of our standard sales contracts, we agree to defend our customers against third-party claims asserting various allegations such as damage resulting from product defects and infringement of certain intellectual property rights, which may include patents, copyrights, trademarks, or trade secrets, and to pay judgments entered on such claims. Our exposure under these indemnification provisions is generally limited by the terms of our contracts to certain defined limits, such as the total amount paid by our customer under the agreement. However, certain agreements include covenants and indemnification provisions including and beyond indemnification for third-party claims of intellectual property infringement and that could potentially expose us to losses in excess of the amount received under the agreement and, in some instances, to potential liability that is not contractually limited. To date, there have been no awards under such indemnification provisions.

Defined Contribution Plans	3 Months Ended
Defined Contribution Plans	Mar. 31, 2015
Compensation and Retirement Disclosure [Abstract]
DEFINED CONTRIBUTION PLANS	DEFINED CONTRIBUTION PLANS Our tax-deferred savings plan under our 401(k) Plan, permits participating employees to defer a portion of their pre-tax earnings. In Canada, we have a Group Registered Retirement Savings Plan program (the “RRSP”) which permits participants to make tax deductible contributions. Our Board approved 50% matching contributions on employee contributions up to 4% of each employee’s eligible earnings. Our matching contributions to the 401(k) Plans and RRSP during the three months ended March 31, 2015 and March 31, 2014 were $0.8 million and $0.6 million, respectively.

Segment and Significant Customer Information (Tables)

3 Months Ended

Mar. 31, 2015

Segment Reporting [Abstract]

Revenue from External Customers by Geographic Areas [Table Text Block]

Revenue by geographic region is based on the billing address of the customer. The following table sets forth revenue (in thousands):



	Three Months Ended
Revenue	March 31, 2015		March 31, 2014
Americas:
United States	$	58,501	$	44,793
Other Americas	33,059		27,639
Total Americas	91,560		72,432
Europe, Middle East, and Africa (“EMEA”)	75,664		56,643
Asia Pacific and Japan (“APAC”)	45,662		39,874
Total revenue	$	212,886	$	168,949

Long-lived Assets by Geographic Areas [Table Text Block]

The following table sets forth property and equipment by geographic region as of March 31, 2015 and December 31, 2014 (in thousands):




Property and Equipment—net	March 31, 2015		December 31, 2014
Americas:
United States	$	49,471	$	46,116
Canada	6,356		6,054
Other Americas	924		875
Total Americas	56,751		53,045
EMEA	3,723		3,256
APAC	3,013		2,618
Total property and equipment—net	$	63,487	$	58,919

Schedule of revenue by major customers [Table Text Block]

The following customers, each of which is a distributor, accounted for 10% or more of our revenue:



	Three Months Ended
	March 31, 2015		March 31, 2014
Exclusive Networks Group	17	%	14	%
Ingram Micro	—	%	10	%

Schedule of receivables by major customers [Table Text Block]

The following customers, each of which is a distributor, accounted for 10% or more of net accounts receivable:



	March 31, 2015		December 31, 2014
Exclusive Networks Group	19	%	18	%
Fine Tec Computer	12	%	—	%

Property and Equipment—Net (Tables)

3 Months Ended

Mar. 31, 2015

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment [Table Text Block]

Property and equipment—net consisted of the following as of March 31, 2015 and December 31, 2014 (in thousands):



	March 31, 2015			December 31, 2014
Land	$	13,895		$	13,895
Building and building improvements	20,224			20,166
Evaluation units	34,053			31,474
Computer equipment and software	38,306			31,821
Furniture and fixtures	5,469			5,096
Construction-in-progress	3,157			3,902
Leasehold improvements	8,711			7,998
Total property and equipment	123,815			114,352
Less: accumulated depreciation	(60,328		)	(55,433		)
Property and equipment—net	$	63,487		$	58,919

Segment and Significant Customer Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2015 USD ($) Segment_Managers business_activity operating_segment reportable_segment	Mar. 31, 2014 USD ($)	Dec. 31, 2014 USD ($)
Segment Reporting Information [Line Items]
Business activity (in business activities) \| business_activity	1
Segment managers responsible for operations (in segment managers) \| Segment_Managers	0
Number of operating segments (in operating segments) \| operating_segment	1
Number of reportable segments (in reportable segments) \| reportable_segment	1
Revenue	$ 212,886	$ 168,949
Property and equipment - net	63,487		$ 58,919
Americas [Member]
Segment Reporting Information [Line Items]
Revenue	91,560	72,432
Property and equipment - net	56,751		53,045
United States
Segment Reporting Information [Line Items]
Revenue	58,501	44,793
Property and equipment - net	49,471		46,116
Canada [Member]
Segment Reporting Information [Line Items]
Property and equipment - net	6,356		6,054
Other Americas [Member]
Segment Reporting Information [Line Items]
Revenue	33,059	27,639
Property and equipment - net	924		875
EMEA [Member]
Segment Reporting Information [Line Items]
Revenue	75,664	56,643
Property and equipment - net	3,723		3,256
APAC [Member]
Segment Reporting Information [Line Items]
Revenue	45,662	$ 39,874
Property and equipment - net	$ 3,013		$ 2,618

Commitments and Contingencies Warranties (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Movement in Standard Product Warranty Accrual [Roll Forward]
Accrued warranty balance—beginning of the period	$ 4,269	$ 3,037
Warranty costs incurred	(1,095)	(756)
Provision for warranty for the period	945	837
Adjustment related to pre-existing warranties	222	(313)
Accrued warranty balance—end of the period	$ 4,341	$ 2,805

Investments in Privately-Held Companies (Details) $ in Millions	3 Months Ended
	Mar. 31, 2015 USD ($) privately_held_company
Investments, All Other Investments [Abstract]
Investments in equity securities of privately-held companies \| $	$ 6.4
Number of privately-held companies \| privately_held_company	3

Defined Contribution Plans (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Matching contribution on employee contributions, Percent	50.00%
Maximum contribtuion percentage of each employee's eligible earnings, Percent	4.00%
Matching contributions to the RRSP and 401(k) Plans	$ 0.8	$ 0.6

Net Income Per Share (Tables)

3 Months Ended

Mar. 31, 2015

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

A reconciliation of the numerator and denominator used in the calculation of basic and diluted net income per share is as follows (in thousands, except per share amounts):



	Three Months Ended
	March 31, 2015		March 31, 2014
Numerator:
Net income	$	1,560	$	8,393

Denominator:
Basic shares:
Weighted-average common stock outstanding—basic	168,077		162,391
Diluted shares:
Weighted-average common stock outstanding—basic	168,077		162,391
Effect of potentially dilutive securities:
Stock options	3,837		5,196
RSUs (including PSUs)	1,741		484
ESPP	65		43
Weighted-average shares used to compute diluted net income per share	173,720		168,114
Net income per share:
Basic	$	0.01	$	0.05
Diluted	$	0.01	$	0.05

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

The following weighted-average shares of common stock were excluded from the computation of diluted net income per share for the periods presented, as their effect would have been anti-dilutive (in thousands):



	Three Months Ended
	March 31, 2015	March 31, 2014
Stock options	249	5,079
RSUs (including PSUs)	1,333	1,348
ESPP	169	358
	1,751	6,785

Stockholders' Equity , Share Repurchase Program (Details) - Share Repurchase Program [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program, authorized amount		$ 200.0
Stock repurchased in the period, shares	0
Remaining authorized repurchase amount under the program	$ 122.5

Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

The following table summarizes the weighted-average assumptions relating to our employee stock options:



	Three Months Ended
	March 31, 2015		March 31, 2014
Expected term in years	4.3		4.9
Volatility	40	%	45	%
Risk-free interest rate	1.5	%	1.7	%
Dividend rate	—	%	—	%

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

The following table summarizes the stock option activity and related information for the periods presented below (in thousands, except exercise prices and contractual life):



	Options Outstanding
	Number of Shares		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
Balance—December 31, 2014	10,702		$	14.98
Granted	269		32.79
Forfeited	(73	)	24.59
Exercised	(1,931	)	10.49
Balance—March 31, 2015	8,967		$	16.41
Options vested and expected to vest—March 31, 2015	8,924		$	16.35	2.8	$	165,975
Options exercisable—March 31, 2015	7,589		$	14.71	2.4	$	153,634

Schedule of Share-based Payment Award, Stock Options, Additional Information [Table Text Block]

Additional information related to our stock options is summarized below (in thousands, except per share amounts):



	Three Months Ended
	March 31, 2015		March 31, 2014
Weighted-average fair value per share granted	$	11.17	$	8.65
Intrinsic value of options exercised	41,003		15,321
Fair value of options vested	3,792		4,562

Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]

The following table summarizes the activity and related information for RSUs for the periods presented below (in thousands, except per share amounts):



	Restricted Stock Units Outstanding
	Number of Shares		Weighted-Average Grant-Date-Fair Value per Share
Balance—December 31, 2014	6,291		$	22.93
Granted	2,492		32.96
Forfeited	(198	)	26.36
Vested	(670	)	22.01
Balance—March 31, 2015	7,915		$	26.18
RSUs expected to vest—March 31, 2015	7,450		$	26.02

Schedule of Share-based Compensation, Shares Withheld for Taxes [Table Text Block]

The following summarizes the number and value of the shares withheld for employee taxes (in thousands):



	Three Months Ended
	March 31, 2015		March 31, 2014
Shares withheld for taxes	221		171
Amount withheld for taxes	$	6,600	$	3,633

Schedule of Share-based Payment Award, Equity Instruments Other than Options, Valuation Assumptions [Table Text Block]

The following table summarizes the weighted-average assumptions relating to our PSUs granted to our executive officers:



	Three Months Ended
	March 31, 2015		March 31, 2014
Expected term in years	3.0		3.0
Volatility	38	%	48	%
Risk-free interest rate	1.1	%	0.7	%
Dividend rate	—	%	—	%

Share-based Compensation, Performance Shares Award Activity [Table Text Block]

The following table summarizes the activity and related information for PSUs for the periods presented below (in thousands, except per share amounts):



	Three Months Ended
	March 31, 2015		March 31, 2014
Shares granted to executive officers and employees	206		25
Weighted-average fair value per share granted	$	34.86	$	22.44

Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]

In determining the fair value of our ESPP, we use the Black-Scholes option pricing model that employs the following weighted-average assumptions:



	Three Months Ended
	March 31, 2015		March 31, 2014
Expected term in years	0.5		0.5
Volatility	28	%	37	%
Risk-free interest rate	0.1	%	0.1	%
Dividend rate	—	%	—	%

Schedule of Share-based Payment Award Employee Stock Purchase Plan Additional Information [Table Text Block]

Additional information related to the ESPP is provided below (in thousands, except per share amounts):



	Three Months Ended
	March 31, 2015		March 31, 2014
Weighted-average fair value per share granted	$	7.56	$	5.76
Shares issued under the ESPP	427		424
Weighted-average price per share issued	$	21.34	$	17.18

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

Stock-based compensation expense is included in costs and expenses as follows (in thousands):



	Three Months Ended
	March 31, 2015		March 31, 2014
Cost of product revenue	$	140	$	113
Cost of service revenue	1,632		1,329
Research and development	5,157		3,882
Sales and marketing	9,307		5,746
General and administrative	2,686		1,860
Total stock-based compensation expense	$	18,922	$	12,930

Schedule of Employee Service Share based Compensation Allocation of Recognized Period Costs by Award Type [Table Text Block]

The following table summarizes stock-based compensation expense by award type (in thousands):



	Three Months Ended
	March 31, 2015		March 31, 2014
Stock options	$	3,455	$	4,692
RSUs (including PSUs)	14,292		7,363
ESPP	1,175		875
Total stock-based compensation expense	$	18,922	$	12,930

Income Tax Benefit from Stock Option Plans [Table Text Block]

Total income tax benefit associated with stock-based compensation that is recognized in the condensed consolidated statements of operations is as follows (in thousands):



	Three Months Ended
	March 31, 2015		March 31, 2014
Income tax benefit associated with stock-based compensation	$	3,377	$	3,349

Financial Instruments and Fair Value Measurements , Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 685,868	$ 709,030
Unrealized Gains	623	384
Unrealized Losses	(278)	(924)
Fair Value	686,213	708,490
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	217,944	356,625
Less Than 12 Months, Unrealized Losses	(249)	(907)
12 Months or Greater, Fair Value	13,142	6,011
12 Months or Greater, Unrealized Losses	(29)	(17)
Total, Fair Value	231,086	362,636
Total, Unrealized Losses	(278)	(924)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Due within one year	417,605	436,766
Due within one to three years	268,608	271,724
Fair Value	686,213	708,490
Corporate debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	568,456	589,526
Unrealized Gains	593	365
Unrealized Losses	(243)	(875)
Fair Value	568,806	589,016
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	177,364	317,011
Less Than 12 Months, Unrealized Losses	(214)	(858)
12 Months or Greater, Fair Value	13,142	6,011
12 Months or Greater, Unrealized Losses	(29)	(17)
Total, Fair Value	190,506	323,022
Total, Unrealized Losses	(243)	(875)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	568,806	589,016
Commercial paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	43,758	51,156
Unrealized Gains	1	3
Unrealized Losses	(9)	(4)
Fair Value	43,750	51,155
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	8,375	8,185
Less Than 12 Months, Unrealized Losses	(9)	(4)
12 Months or Greater, Fair Value	0	0
12 Months or Greater, Unrealized Losses	0	0
Total, Fair Value	8,375	8,185
Total, Unrealized Losses	(9)	(4)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	43,750	51,155
Municipal bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	49,825	39,745
Unrealized Gains	21	15
Unrealized Losses	(26)	(39)
Fair Value	49,820	39,721
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	32,205	26,684
Less Than 12 Months, Unrealized Losses	(26)	(39)
12 Months or Greater, Fair Value	0	0
12 Months or Greater, Unrealized Losses	0	0
Total, Fair Value	32,205	26,684
Total, Unrealized Losses	(26)	(39)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	49,820	39,721
Certificates of deposit and term deposits [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	13,080	22,854
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	13,080	22,854
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	13,080	22,854
U.S. government and agency securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	10,749	5,749
Unrealized Gains	8	1
Unrealized Losses	0	(6)
Fair Value	10,757	5,744
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value		4,745
Less Than 12 Months, Unrealized Losses		(6)
12 Months or Greater, Fair Value		0
12 Months or Greater, Unrealized Losses		0
Total, Fair Value		4,745
Total, Unrealized Losses		(6)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	$ 10,757	$ 5,744

Deferred Revenue (Tables)

3 Months Ended

Mar. 31, 2015

Deferred Revenue Disclosure [Abstract]

Deferred Revenue, by Arrangement, Disclosure [Table Text Block]

Deferred revenue consisted of the following as of March 31, 2015 and December 31, 2014 (in thousands):



	March 31, 2015		December 31, 2014
Product	$	4,255	$	4,642
Service	595,916		554,115
Total deferred revenue	$	600,171	$	558,757
Reported As:
Current	$	406,526	$	368,929
Non-current	193,645		189,828
Total deferred revenue	$	600,171	$	558,757

Summary of Significant Accounting Policies (Policies)	3 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2015
Accounting Policies [Abstract]
Basis of Presentation and Preparation	Basis of Presentation and Preparation—The unaudited condensed consolidated financial statements of Fortinet, Inc. and its wholly-owned subsidiaries (collectively, “we,” “us” or “our”) have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) for interim financial information as well as the instructions to Form 10-Q pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements, and should be read in conjunction with our audited consolidated financial statements as of and for the year ended December 31, 2014, contained in our Annual Report on Form 10-K (“Form 10-K”) filed with the SEC on March 2, 2015. In the opinion of management, all adjustments, which includes normal recurring adjustments, considered necessary for a fair presentation have been included. All intercompany balances, transactions and cash flows have been eliminated. The results of operations for the three months ended March 31, 2015 are not necessarily indicative of the results for the full year or for any future periods. The condensed consolidated balance sheet as of December 31, 2014 is derived from the audited consolidated financial statements for the year ended December 31, 2014.
Use of Estimates	The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Actual results could differ materially from those estimates.
Foreign Currency Translation and Transaction Gains and Losses	In the third quarter of 2014, we reevaluated the selected functional currency of our international subsidiaries due to the nature of our business operations and recorded the cumulative impact of the reevaluation of the functional currency in the consolidated statement of operations. Subsequently, the remeasurement of the assets and liabilities of all international subsidiaries has been recorded in the consolidated statement of operations prospectively. The impact of this reevaluation is not material for our fiscal 2014 or any of our previously issued financial statements.
Recent Accounting Pronouncement	Recent Accounting Pronouncement In May 2014, the Financial Accounting Standards Board issued Accounting Standards Update No. 2014-09—Revenue from Contracts with Customers (Topic 606) (“ASU 2014-09”) to create a single, joint revenue standard that is consistent across all industries and markets for companies that prepare their financial statements in accordance with GAAP. Under ASU 2014-09, an entity is required to recognize revenue upon the transfer of promised goods or services to customers in an amount that reflects the consideration the entity expects to be entitled to receive in exchange for those goods or services. ASU 2014-09 is effective for us beginning on January 1, 2017. We are currently evaluating the impact of ASU 2014-09 on our consolidated financial statements.

Inventory (Tables)

3 Months Ended

Mar. 31, 2015

Inventory Disclosure [Abstract]

Inventory [Table Text Block]

Inventory consisted of the following as of March 31, 2015 and December 31, 2014 (in thousands):



	March 31, 2015		December 31, 2014
Raw materials	$	12,077	$	10,617
Finished goods	59,983		58,860
Inventory	$	72,060	$	69,477

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 1,560	$ 8,393
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	6,353	4,422
Amortization of investment premiums	1,938	2,513
Stock-based compensation	18,880	12,930
Excess tax benefit from stock-based compensation	0	(579)
Other non-cash items—net	159	(67)
Changes in operating assets and liabilities:
Accounts receivable—net	23,621	19,119
Inventory	(6,296)	3,326
Deferred tax assets	(7,918)	24
Prepaid expenses and other current assets	(1,203)	(287)
Other assets	507	45
Accounts payable	(11,305)	(6,042)
Accrued liabilities	(3,450)	(170)
Accrued payroll and compensation	(1,569)	16,155
Other liabilities	(3,149)	1,071
Deferred revenue	40,696	18,469
Income taxes payable	5,795	(18,420)
Net cash provided by operating activities	64,619	60,902
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of investments	(120,991)	(120,590)
Sales of investments	6,679	10,920
Maturities of investments	135,363	118,641
Purchases of property and equipment	(4,927)	(11,318)
Payments made in connection with business acquisitions—net of cash acquired	0	(17)
Net cash provided by (used in) investing activities	16,124	(2,364)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock	28,955	14,471
Taxes paid related to net share settlement of equity awards	(6,600)	(3,633)
Excess tax benefit from stock-based compensation	0	579
Repurchase and retirement of common stock	0	(12,305)
Net cash provided by (used in) financing activities	22,355	(888)
EFFECT OF EXCHANGE RATES ON CASH AND CASH EQUIVALENTS	0	(555)
NET INCREASE IN CASH AND CASH EQUIVALENTS	103,098	57,095
CASH AND CASH EQUIVALENTS—Beginning of period	283,254	115,873
CASH AND CASH EQUIVALENTS—End of period	386,352	172,968
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Cash paid for income taxes—net	6,498	22,136
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Transfers of evaluation units from inventory to property and equipment	3,869	2,307
Liability for purchase of property and equipment and asset retirement obligations	2,140	5,844
Liability incurred for repurchase of common stock	$ 0	$ 657

Condensed Consolidated Balance Sheets Parenthetical (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Mar. 31, 2015	Dec. 31, 2014
Sales returns reserve and allowance for doubtful accounts	$ 4,882	$ 6,204
Common Stock, par value (dollars per share)	$ 0.001	$ 0.001
Common Stock, shares authorized	300,000	300,000
Common Stock, shares issued	169,247	166,443
Common Stock, shares outstanding	169,247	166,443

Accumulated Other Comprehensive Income (Loss)

3 Months Ended

Mar. 31, 2015

Other Comprehensive Income (Loss), Net of Tax [Abstract]

ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)

The following table summarizes the changes in accumulated balances of other comprehensive income (loss) (in thousands):



	Unrealized Gains (Losses) on Investments			Tax benefit (provision) related to items of other comprehensive income (loss)			Total
Beginning balance as of December 31, 2014	$	(540	)	$	191		$	(349	)
Other comprehensive income before reclassifications	889			(311		)	578
Amounts reclassified from accumulated other comprehensive income (loss)	(4		)	1			(3		)
Net current-period other comprehensive income	885			(310		)	575
Ending balance as of March 31, 2015	$	345		$	(119	)	$	226

The following table provides details about the reclassification out of accumulated other comprehensive income (loss) (in thousands):



Three Months Ended March 31, 2015
Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income			Affected Line Item in the Statement Where Net Income is Presented
Unrealized gains on investments	$	(4	)	Other expense—net
Tax provision related to items of other comprehensive income	1			Provision for income taxes
Total reclassification for the period	$	(3	)

- Definition

The entire disclosure for comprehensive income, which includes, but is not limited to, 1) the amount of income tax expense or benefit allocated to each component of other comprehensive income, including reclassification adjustments, 2) the reclassification adjustments for each classification of other comprehensive income and 3) the ending accumulated balances for each component of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e689-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669619-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e640-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e716-108580

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e709-108580

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e681-108580

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Reclassification Adjustments
-URI http://asc.fasb.org/extlink&oid=6522872

+ Details

Stockholders' Equity

3 Months Ended

Mar. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

STOCKHOLDERS' EQUITY

STOCKHOLDERS’ EQUITY

Stock-Based Compensation Plans

We have stock-based compensation plans pursuant to which we have granted stock options and RSUs, including PSUs. The Company also has an ESPP for all eligible employees. As of March 31, 2015, there were a total of 44,040,580 shares of common stock available for grant under our stock-based compensation plans.

Employee Stock Options

The following table summarizes the weighted-average assumptions relating to our employee stock options:



	Three Months Ended
	March 31, 2015		March 31, 2014
Expected term in years	4.3		4.9
Volatility	40	%	45	%
Risk-free interest rate	1.5	%	1.7	%
Dividend rate	—	%	—	%

The following table summarizes the stock option activity and related information for the periods presented below (in thousands, except exercise prices and contractual life):



	Options Outstanding
	Number of Shares		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
Balance—December 31, 2014	10,702		$	14.98
Granted	269		32.79
Forfeited	(73	)	24.59
Exercised	(1,931	)	10.49
Balance—March 31, 2015	8,967		$	16.41
Options vested and expected to vest—March 31, 2015	8,924		$	16.35	2.8	$	165,975
Options exercisable—March 31, 2015	7,589		$	14.71	2.4	$	153,634

The aggregate intrinsic value represents the pre-tax difference between the exercise price of stock options and the quoted market price of our common stock on March 31, 2015, for all in-the-money options. As of March 31, 2015, total compensation expense related to unvested stock options granted to employees but not yet recognized was $15.6 million, net of estimated forfeitures. This expense is expected to be amortized on a straight-line basis over a weighted-average period of 1.8 years.

Additional information related to our stock options is summarized below (in thousands, except per share amounts):



	Three Months Ended
	March 31, 2015		March 31, 2014
Weighted-average fair value per share granted	$	11.17	$	8.65
Intrinsic value of options exercised	41,003		15,321
Fair value of options vested	3,792		4,562

Restricted Stock Units

The following table summarizes the activity and related information for RSUs for the periods presented below (in thousands, except per share amounts):



	Restricted Stock Units Outstanding
	Number of Shares		Weighted-Average Grant-Date-Fair Value per Share
Balance—December 31, 2014	6,291		$	22.93
Granted	2,492		32.96
Forfeited	(198	)	26.36
Vested	(670	)	22.01
Balance—March 31, 2015	7,915		$	26.18
RSUs expected to vest—March 31, 2015	7,450		$	26.02

As of March 31, 2015, total compensation expense related to unvested RSUs that were granted to employees and non-employees, but not yet recognized, was $197.8 million, net of estimated forfeitures. This expense is expected to be amortized on a straight-line basis over a weighted-average vesting period of 3.1 years.

RSUs settle into shares of common stock upon vesting. Upon the vesting of the RSUs, we net-settle the RSUs and withhold a portion of the shares to satisfy minimum statutory employee withholding taxes. Total payment for the employees’ tax obligations to the taxing authorities is reflected as a financing activity within the condensed consolidated statements of cash flows.

The following summarizes the number and value of the shares withheld for employee taxes (in thousands):



	Three Months Ended
	March 31, 2015		March 31, 2014
Shares withheld for taxes	221		171
Amount withheld for taxes	$	6,600	$	3,633

Performance Stock Units

We have granted PSUs to certain of our executive officers and employees. PSUs granted to executive officers are based on the achievement of the market-based vesting conditions during the performance period, the final settlement of the PSUs will range between 0% and 150% of the target shares underlying the PSUs based on a specified objective formula approved by our Compensation Committee. The PSUs entitle our executive officers to receive a number of shares of our common stock based on the performance of our stock price over a two- or three-year period as compared to the NASDAQ Composite index for the same periods. PSUs granted to certain employees are based on the achievement of personal- and company-based performance vesting conditions during the performance period. The final settlement of these PSUs will range between 50% to 150% of the target shares underlying the PSUs based on specified objective formula approved by our Compensation Committee. The PSUs entitle the employees to receive a number of shares of our common stock based on a one year performance period, and vest equally in the second and third years.

The following table summarizes the weighted-average assumptions relating to our PSUs granted to our executive officers:



	Three Months Ended
	March 31, 2015		March 31, 2014
Expected term in years	3.0		3.0
Volatility	38	%	48	%
Risk-free interest rate	1.1	%	0.7	%
Dividend rate	—	%	—	%

The following table summarizes the activity and related information for PSUs for the periods presented below (in thousands, except per share amounts):



	Three Months Ended
	March 31, 2015		March 31, 2014
Shares granted to executive officers and employees	206		25
Weighted-average fair value per share granted	$	34.86	$	22.44

As of March 31, 2015, total compensation expense related to unvested PSUs that were granted to certain of our executive officers and employees, but not yet recognized, was $9.5 million, net of estimated forfeitures. This expense is expected to be amortized on a straight-line basis over a weighted-average vesting period of 2.5 years.

Employee Stock Purchase Plan

In determining the fair value of our ESPP, we use the Black-Scholes option pricing model that employs the following weighted-average assumptions:



	Three Months Ended
	March 31, 2015		March 31, 2014
Expected term in years	0.5		0.5
Volatility	28	%	37	%
Risk-free interest rate	0.1	%	0.1	%
Dividend rate	—	%	—	%

Additional information related to the ESPP is provided below (in thousands, except per share amounts):



	Three Months Ended
	March 31, 2015		March 31, 2014
Weighted-average fair value per share granted	$	7.56	$	5.76
Shares issued under the ESPP	427		424
Weighted-average price per share issued	$	21.34	$	17.18

Stock-based Compensation Expense

Stock-based compensation expense is included in costs and expenses as follows (in thousands):



	Three Months Ended
	March 31, 2015		March 31, 2014
Cost of product revenue	$	140	$	113
Cost of service revenue	1,632		1,329
Research and development	5,157		3,882
Sales and marketing	9,307		5,746
General and administrative	2,686		1,860
Total stock-based compensation expense	$	18,922	$	12,930

The following table summarizes stock-based compensation expense by award type (in thousands):



	Three Months Ended
	March 31, 2015		March 31, 2014
Stock options	$	3,455	$	4,692
RSUs (including PSUs)	14,292		7,363
ESPP	1,175		875
Total stock-based compensation expense	$	18,922	$	12,930

Total income tax benefit associated with stock-based compensation that is recognized in the condensed consolidated statements of operations is as follows (in thousands):



	Three Months Ended
	March 31, 2015		March 31, 2014
Income tax benefit associated with stock-based compensation	$	3,377	$	3,349

Share Repurchase Program

In December 2013, our Board of Directors (“Board”) authorized a Share Repurchase Program (“Program”) to repurchase up to $200.0 million of our outstanding common stock through December 31, 2014. Under the Program, share repurchases may be made by us from time to time in privately negotiated transactions or in open market transactions. The Program does not require us to purchase a minimum number of shares, and may be suspended, modified or discontinued at any time without prior notice. In October 2014, our Board extended the share repurchase authorization under the Program through December 31, 2015. During the three months ended March 31, 2015, there were no shares repurchased under the Program. As of March 31, 2015, $122.5 million remains available for future share repurchases under the Program.

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2015	Dec. 31, 2014
CURRENT ASSETS:
Cash and cash equivalents	$ 386,352	$ 283,254
Short-term investments	417,605	436,766
Accounts receivable—Net of sales returns reserve and allowance for doubtful accounts of $4,882 and $6,204 as of March 31, 2015 and December 31, 2014, respectively	161,854	184,741
Inventory	72,060	69,477
Deferred tax assets	41,175	41,484
Prepaid expenses and other current assets	32,757	31,143
Total current assets	1,111,803	1,046,865
LONG-TERM INVESTMENTS	268,608	271,724
PROPERTY AND EQUIPMENT—Net	63,487	58,919
DEFERRED TAX ASSETS	38,998	31,080
GOODWILL	2,824	2,824
OTHER INTANGIBLE ASSETS—Net	2,559	2,832
OTHER ASSETS	10,024	10,530
TOTAL ASSETS	1,498,303	1,424,774
CURRENT LIABILITIES:
Accounts payable	40,164	49,947
Accrued liabilities	25,873	29,016
Accrued payroll and compensation	42,727	45,875
Income taxes payable	3,343	2,689
Deferred revenue	406,526	368,929
Total current liabilities	518,633	496,456
DEFERRED REVENUE	193,645	189,828
INCOME TAXES PAYABLE	50,280	45,139
OTHER LIABILITIES	15,998	17,385
Total liabilities	778,556	748,808
COMMITMENTS AND CONTINGENCIES (Note 8)
STOCKHOLDERS’ EQUITY:
Common stock, $0.001 par value — 300,000 shares authorized; 169,247 and 166,443 shares issued and outstanding as of March 31, 2015 and December 31, 2014, respectively	169	166
Additional paid-in capital	604,147	562,504
Accumulated other comprehensive income (loss)	226	(349)
Retained earnings	115,205	113,645
Total stockholders’ equity	719,747	675,966
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 1,498,303	$ 1,424,774

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Effective income tax rate (percent)	5.00%	39.00%
Unrecognized tax benefits	$ 46.6		$ 44.2
Unrecognized tax benefits that would favoraby affect effective tax rate	46.6
Accrued interest and penalties related to uncertain tax benefits	$ 4.5

Foreign Currency Derivatives (Details) - USD ($) $ in Thousands	Mar. 31, 2015	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Notional amount of forward exchange contracts	$ 9,093	$ 6,879

Stockholders' Equity , Performance Stock Units (Details) - Performance Shares [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Performance Share, Weighted Average Assumptions [Abstract]
Expected term in years	2 years 11 months 19 days	2 years 11 months 19 days
Volatility	38.00%	48.00%
Risk-free interest rate	1.10%	0.70%
Dividend rate	0.00%	0.00%
Granted	206	25
Granted, weighted-average grant-date fair value per share (in dollars per share)	$ 34.86	$ 22.44
Compensation cost not yet recognized	$ 9.5
Compensation cost not yet recognized period of recognition	2 years 6 months 18 days
Market-based [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share target range, percent	0.00%
Performance period	2 years
Market-based [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share target range, percent	150.00%
Performance period	3 years
Performance-based [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period	1 year
Performance-based [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share target range, percent	50.00%
Performance-based [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share target range, percent	150.00%

Net Income Per Share

3 Months Ended

Mar. 31, 2015

Earnings Per Share [Abstract]

NET INCOME PER SHARE

Basic net income per share is computed by dividing net income by the weighted-average number of shares of common stock outstanding during the period. Diluted net income per share is computed by dividing net income by the weighted-average number of shares of common stock outstanding, plus the dilutive effects of stock options, restricted stock units (“RSUs”) including performance stock units (“PSUs”), and the employee stock purchase plan (“ESPP”). Dilutive shares of common stock are determined by applying the treasury stock method.

A reconciliation of the numerator and denominator used in the calculation of basic and diluted net income per share is as follows (in thousands, except per share amounts):



	Three Months Ended
	March 31, 2015		March 31, 2014
Numerator:
Net income	$	1,560	$	8,393

Denominator:
Basic shares:
Weighted-average common stock outstanding—basic	168,077		162,391
Diluted shares:
Weighted-average common stock outstanding—basic	168,077		162,391
Effect of potentially dilutive securities:
Stock options	3,837		5,196
RSUs (including PSUs)	1,741		484
ESPP	65		43
Weighted-average shares used to compute diluted net income per share	173,720		168,114
Net income per share:
Basic	$	0.01	$	0.05
Diluted	$	0.01	$	0.05



	Three Months Ended
	March 31, 2015	March 31, 2014
Stock options	249	5,079
RSUs (including PSUs)	1,333	1,348
ESPP	169	358
	1,751	6,785

Inventory

3 Months Ended

Mar. 31, 2015

Inventory Disclosure [Abstract]

INVENTORY

Inventory consisted of the following as of March 31, 2015 and December 31, 2014 (in thousands):



	March 31, 2015		December 31, 2014
Raw materials	$	12,077	$	10,617
Finished goods	59,983		58,860
Inventory	$	72,060	$	69,477

Inventory includes finished goods held by distributors where revenue is recognized on a sell-through basis of $1.0 million and $1.2 million as of March 31, 2015 and December 31, 2014, respectively. Inventory also includes materials at contract manufacturers of $4.6 million and $4.8 million as of March 31, 2015 and December 31, 2014, respectively.

Related Party Transactions	3 Months Ended
Related Party Transactions	Mar. 31, 2015
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	RELATED PARTY TRANSACTIONS The son of one member of our Board is a partner of an outside law firm that we utilize for certain complex litigation matters. Expenses for legal services provided by the law firm related to matters that arose subsequent to the member joining our Board were $1.9 million and $0.3 million for the three months ended March 31, 2015 and March 31, 2014, respectively. Amounts due and payable to the law firm were $1.7 million and $1.3 million as of March 31, 2015 and December 31, 2014, respectively.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References + Details

Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected term in years	4 years 3 months 26 days	4 years 10 months 17 days
Volatility	40.00%	45.00%
Risk-free interest rate	1.50%	1.70%
Dividend rate	0.00%	0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Balance - Beginning (in shares)	10,702,000
Granted (in shares)	269,000
Forfeited (in shares)	(73,000)
Exercised (in shares)	(1,931,000)
Balance - Ending (in shares)	8,967,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Balance - Beginning (in dollars per share)	$ 14.98
Granted (in dollars per share)	32.79
Forfeited (in dollars per share)	24.59
Exercised (in dollars per share)	10.49
Balance - Ending (in dollars per share)	$ 16.41
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options vested and expected to vest, Outstanding (in shares)	8,924,000
Options vested and expected to vest, Weighted average exercise price (in dollars per share)	$ 16.35
Options vested and expected to vest, Weighted average remaining contractual life (in years)	2 years 9 months 17 days
Options vested and expected to vest, Aggregate intrinsic value	$ 165,975
Options exercisable, Outstanding (in shares)	7,589,000
Options exercisable, Weighted average exercise price (in dollars per share)	$ 14.71
Options exercisable, Weighted average remaining contractual life (in years)	2 years 4 months 27 days
Options exercisable, Aggregate intrinsic value	$ 153,634
Compensation cost not yet recognized	$ 15,600
Compensation cost not yet recognized period of recognition	1 year 9 months 30 days
Weighted-average fair value per share granted	$ 11.17	$ 8.65
Intrinsic value of options exercised	$ 41,003	$ 15,321
Total fair value of awards vested	$ 3,792	$ 4,562
Share-based Compensation Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (shares)	44,040,580

Stockholders' Equity , ESPP Information (Details) - Employee Stock Purchase Plan [Member] - $ / shares shares in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term in years	5 months 27 days	5 months 27 days
Volatility	28.00%	37.00%
Risk-free interest rate	0.10%	0.10%
Dividend rate	0.00%	0.00%
Weighted-average fair value per share granted (in dollars per share)	$ 7.56	$ 5.76
Shares issued under the ESPP (in shares)	427	424
Weighted-average price per share issued (in dollars per share)	$ 21.34	$ 17.18

Summary of Significant Accounting Policies	3 Months Ended
Summary of Significant Accounting Policies	Mar. 31, 2015
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation and Preparation—The unaudited condensed consolidated financial statements of Fortinet, Inc. and its wholly-owned subsidiaries (collectively, “we,” “us” or “our”) have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) for interim financial information as well as the instructions to Form 10-Q pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements, and should be read in conjunction with our audited consolidated financial statements as of and for the year ended December 31, 2014, contained in our Annual Report on Form 10-K (“Form 10-K”) filed with the SEC on March 2, 2015. In the opinion of management, all adjustments, which includes normal recurring adjustments, considered necessary for a fair presentation have been included. All intercompany balances, transactions and cash flows have been eliminated. The results of operations for the three months ended March 31, 2015 are not necessarily indicative of the results for the full year or for any future periods. The condensed consolidated balance sheet as of December 31, 2014 is derived from the audited consolidated financial statements for the year ended December 31, 2014. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Actual results could differ materially from those estimates. There have been no material changes to our significant accounting policies as of and for the three months ended March 31, 2015. In the third quarter of 2014, we reevaluated the selected functional currency of our international subsidiaries due to the nature of our business operations and recorded the cumulative impact of the reevaluation of the functional currency in the consolidated statement of operations. Subsequently, the remeasurement of the assets and liabilities of all international subsidiaries has been recorded in the consolidated statement of operations prospectively. The impact of this reevaluation is not material for our fiscal 2014 or any of our previously issued financial statements. Recent Accounting Pronouncement In May 2014, the Financial Accounting Standards Board issued Accounting Standards Update No. 2014-09—Revenue from Contracts with Customers (Topic 606) (“ASU 2014-09”) to create a single, joint revenue standard that is consistent across all industries and markets for companies that prepare their financial statements in accordance with GAAP. Under ASU 2014-09, an entity is required to recognize revenue upon the transfer of promised goods or services to customers in an amount that reflects the consideration the entity expects to be entitled to receive in exchange for those goods or services. ASU 2014-09 is effective for us beginning on January 1, 2017. We are currently evaluating the impact of ASU 2014-09 on our consolidated financial statements.

Accumulated Other Comprehensive Income (Loss) (Tables)

3 Months Ended

Mar. 31, 2015

Other Comprehensive Income (Loss), Net of Tax [Abstract]

Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]

The following table summarizes the changes in accumulated balances of other comprehensive income (loss) (in thousands):



	Unrealized Gains (Losses) on Investments			Tax benefit (provision) related to items of other comprehensive income (loss)			Total
Beginning balance as of December 31, 2014	$	(540	)	$	191		$	(349	)
Other comprehensive income before reclassifications	889			(311		)	578
Amounts reclassified from accumulated other comprehensive income (loss)	(4		)	1			(3		)
Net current-period other comprehensive income	885			(310		)	575
Ending balance as of March 31, 2015	$	345		$	(119	)	$	226

Reclassification out of Accumulated Other Comprehensive Income (Loss) [Table Text Block]

The following table provides details about the reclassification out of accumulated other comprehensive income (loss) (in thousands):



Three Months Ended March 31, 2015
Details about Accumulated Other Comprehensive Income Components	Amount Reclassified from Accumulated Other Comprehensive Income			Affected Line Item in the Statement Where Net Income is Presented
Unrealized gains on investments	$	(4	)	Other expense—net
Tax provision related to items of other comprehensive income	1			Provision for income taxes
Total reclassification for the period	$	(3	)

Foreign Currency Derivatives

3 Months Ended

Mar. 31, 2015

Derivative Instruments and Hedging Activities Disclosure [Abstract]

FOREIGN CURRENCY DERIVATIVES

Our sales contracts are primarily denominated in U.S. dollars and therefore substantially all of our revenue is not subject to foreign currency translation risk. However, a substantial portion of our operating expenses incurred outside the U.S. are denominated in foreign currencies and are subject to fluctuations due to changes in foreign currency exchange rates, particularly changes in the Canadian dollar (“CAD”) and the Euro (“EUR”). To help protect against significant fluctuations in value and the volatility of future cash flows caused by changes in currency exchange rates, we engage in foreign currency risk management activities, including forward contracts, to hedge balance sheet items denominated in CAD. We do not use these contracts for speculative or trading purposes. All of the derivative instruments are with high quality financial institutions and we monitor the creditworthiness of these parties. These contracts typically have maturities of one month. We record changes in the fair value of forward exchange contracts related to balance sheet accounts as Other expense—net in the condensed consolidated statement of operations.

Additionally, independent of any hedging activities, fluctuations in foreign currency exchange rates may cause us to recognize transaction gains and losses in Other expense—net in our condensed consolidated statements of operations. Our hedging activities are intended to reduce, but not eliminate, the impact of currency exchange rate movements. As our hedging activities are relatively short-term in nature and are focused on CAD, long-term material changes in the value of the U.S. dollar against other foreign currencies, such as the GBP and EUR could adversely impact our operating expenses in the future.

The notional amount of forward exchange contracts to hedge balance sheet accounts were (in thousands):



	Buy/Sell	Notional
Currency—As of March 31, 2015
CAD	Sell	$	9,093

Currency—As of December 31, 2014
CAD	Buy	$	6,879

- Definition

The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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+ Details

Related Party Transactions (Details) - Law Firm where Board Member's Son is a Partner [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Related Party Transaction [Line Items]
Expenses for legal services	$ 1.9	$ 0.3
Amounts due and payable to the law firm	$ 1.7		$ 1.3

Net Income Per Share , Calculation of Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Line Items]
Net income	$ 1,560	$ 8,393
Basic shares:
Weighted-average common shares outstanding-basic (in shares)	168,077	162,391
Diluted shares:
Weighted-average common shares outstanding-basic (in shares)	168,077	162,391
Effect of potentially dilutive securities:
Weighted-average shares used to compute diluted net income per share (in shares)	173,720	168,114
Basic (in dollars per share)	$ 0.01	$ 0.05
Diluted (in dollars per share)	$ 0.01	$ 0.05
Stock options [Member]
Effect of potentially dilutive securities:
Employee stock options and purchase rights (in shares)	3,837	5,196
RSUs (including PSUs) [Member]
Effect of potentially dilutive securities:
Employee stock options and purchase rights (in shares)	1,741	484
ESPP [Member]
Effect of potentially dilutive securities:
Employee stock options and purchase rights (in shares)	65	43

Property and Equipment—Net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	$ 123,815		$ 114,352
Less: accumulated depreciation	(60,328)		(55,433)
Property and equipment - net	63,487		58,919
Depreciation expense	6,000	$ 3,900
Land [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	13,895		13,895
Building and building improvements [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	20,224		20,166
Evaluation units [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	34,053		31,474
Computer equipment and software [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	38,306		31,821
Furniture and fixtures [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	5,469		5,096
Construction-in-progress [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	3,157		3,902
Leasehold improvements [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	$ 8,711		$ 7,998

Segment and Significant Customer Information Significant Customers (Details) - Customer Concentration Risk [Member]	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Sales Revenue [Member] \| Exclusive Networks Group [Member]
Concentration Risk [Line Items]
Percentage from a single customer	17.00%	14.00%
Sales Revenue [Member] \| Ingram Micro [Member]
Concentration Risk [Line Items]
Percentage from a single customer	0.00%	10.00%
Accounts Receivable [Member] \| Exclusive Networks Group [Member]
Concentration Risk [Line Items]
Percentage from a single customer	19.00%	18.00%
Accounts Receivable [Member] \| Fin Tec Computer [Member]
Concentration Risk [Line Items]
Percentage from a single customer	12.00%	0.00%

Stockholders' Equity , Restricted Stock Units Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Tax withholding upon vesting of restricted stock awards	$ 6,600	$ 3,633
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Balance, beginning	6,291
Granted	2,492
Forfeited	(198)
Vested	(670)
Balance, ending	7,915
RSUs expected to vest—March 31, 2015	7,450
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Balance, weighted-average grant-date fair value per share (in dollars per share)—beginning	$ 22.93
Granted, weighted-average grant-date fair value per share (in dollars per share)	32.96
Forfeited, weighted-average grant-date fair value per share (in dollars per share)	26.36
Vested, weighted-average grant-date fair value per share (in dollars per share)	22.01
Balance, weighted-average grant-date fair value per share (in dollars per share)—ending	26.18
RSUs expected to vest, weighted-average grant-date fair value per share (in dollars per share)—December 31, 2012	$ 26.02
Compensation cost not yet recognized	$ 197,800
Compensation cost not yet recognized period of recognition	3 years 1 month 13 days
Shares withheld for taxes	221	171
Tax withholding upon vesting of restricted stock awards	$ 6,600	$ 3,633

Financial Instruments and Fair Value Measurements , Fair Value Measurements (Details) - Recurring [Member] - USD ($) $ in Thousands	Mar. 31, 2015	Dec. 31, 2014
Estimate of Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	$ 715,367	$ 721,801
Estimate of Fair Value [Member] \| Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	31,155	15,309
Estimate of Fair Value [Member] \| Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	684,212	706,492
Estimate of Fair Value [Member] \| Corporate debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	568,806	589,016
Estimate of Fair Value [Member] \| Corporate debt securities [Member] \| Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	0	0
Estimate of Fair Value [Member] \| Corporate debt securities [Member] \| Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	568,806	589,016
Estimate of Fair Value [Member] \| Commercial paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	43,750	51,155
Estimate of Fair Value [Member] \| Commercial paper [Member] \| Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	0	0
Estimate of Fair Value [Member] \| Commercial paper [Member] \| Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	43,750	51,155
Estimate of Fair Value [Member] \| Municipal bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	49,820	39,721
Estimate of Fair Value [Member] \| Municipal bonds [Member] \| Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	0	0
Estimate of Fair Value [Member] \| Municipal bonds [Member] \| Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	49,820	39,721
Estimate of Fair Value [Member] \| Certificates of deposit and term deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	13,080	22,854
Estimate of Fair Value [Member] \| Certificates of deposit and term deposits [Member] \| Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	0	0
Estimate of Fair Value [Member] \| Certificates of deposit and term deposits [Member] \| Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	13,080	22,854
Estimate of Fair Value [Member] \| Money market funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	29,154	13,311
Estimate of Fair Value [Member] \| Money market funds [Member] \| Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	29,154	13,311
Estimate of Fair Value [Member] \| Money market funds [Member] \| Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	0	0
Estimate of Fair Value [Member] \| U.S. government and agency securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	10,757	5,744
Estimate of Fair Value [Member] \| U.S. government and agency securities [Member] \| Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	2,001	1,998
Estimate of Fair Value [Member] \| U.S. government and agency securities [Member] \| Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	8,756	3,746
Reported as [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	715,367	721,801
Reported as [Member] \| Cash equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	29,154	13,311
Reported as [Member] \| Short-term investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	417,605	436,766
Reported as [Member] \| Long-term investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	$ 268,608	$ 271,724