Fortinet (FTNT) 10-Q 9 Nov 15 2015 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Oct. 30, 2015
Document Information [Line Items]
Entity Registrant Name	FORTINET INC
Entity Central Index Key	1,262,039
Document Type	10-Q
Document Period End Date	Sep. 30, 2015
Amendment Flag	false
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		172,264,048

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
CURRENT ASSETS:
Cash and cash equivalents	$ 540,712	$ 283,254
Short-term investments	367,446	436,766
Accounts receivable—net of sales returns reserve and allowance for doubtful accounts of $5,488 and $6,204 as of September 30, 2015 and December 31, 2014, respectively	174,111	184,741
Inventory	80,650	69,477
Deferred tax assets	47,304	41,484
Prepaid expenses and other current assets	41,517	31,143
Total current assets	1,251,740	1,046,865
LONG-TERM INVESTMENTS	261,506	271,724
PROPERTY AND EQUIPMENT—net	83,372	58,919
DEFERRED TAX ASSETS	72,003	31,080
GOODWILL	4,260	2,824
OTHER INTANGIBLE ASSETS—net	18,967	2,832
OTHER ASSETS	15,325	10,530
TOTAL ASSETS	1,707,173	1,424,774
CURRENT LIABILITIES:
Accounts payable	48,793	49,947
Accrued liabilities	29,831	29,016
Accrued payroll and compensation	47,915	45,875
Income taxes payable	5,477	2,689
Deferred revenue	471,118	368,929
Total current liabilities	603,134	496,456
DEFERRED REVENUE	235,793	189,828
INCOME TAXES PAYABLE	56,906	45,139
OTHER LIABILITIES	15,954	17,385
Total liabilities	$ 911,787	$ 748,808
COMMITMENTS AND CONTINGENCIES (Note 11)
STOCKHOLDERS’ EQUITY:
Common stock, $0.001 par value — 300,000 shares authorized; 172,402 and 166,443 shares issued and outstanding as of September 30, 2015 and December 31, 2014, respectively	$ 172	$ 166
Additional paid-in capital	671,138	562,504
Accumulated other comprehensive loss	(90)	(349)
Retained earnings	124,166	113,645
Total stockholders’ equity	795,386	675,966
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 1,707,173	$ 1,424,774

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets Parenthetical (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Sales returns reserve and allowance for doubtful accounts	$ 5,488	$ 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	172,402	166,443
Common Stock, shares outstanding	172,402	166,443

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
REVENUE:
Product	$ 119,737	$ 87,731	$ 332,023	$ 249,880
Service	140,331	105,617	380,716	296,515
Total revenue	260,068	193,348	712,739	546,395
COST OF REVENUE:
Product	46,167	35,636	134,932	105,230
Service	25,534	21,249	69,869	60,155
Total cost of revenue	71,701	56,885	204,801	165,385
GROSS PROFIT:
Product	73,570	52,095	197,091	144,650
Service	114,797	84,368	310,847	236,360
Total gross profit	188,367	136,463	507,938	381,010
OPERATING EXPENSES:
Research and development	42,110	30,790	115,315	89,783
Sales and marketing	120,994	80,433	333,531	222,576
General and administrative	21,220	9,789	51,199	29,243
Restructuring charges	5,883	0	5,883	0
Total operating expenses	190,207	121,012	505,928	341,602
OPERATING INCOME (LOSS)	(1,840)	15,451	2,010	39,408
INTEREST INCOME	1,333	1,339	4,119	3,991
OTHER EXPENSE—net	(653)	(1,005)	(2,160)	(1,968)
INCOME (LOSS) BEFORE INCOME TAXES	(1,160)	15,785	3,969	41,431
PROVISION FOR (BENEFIT FROM) INCOME TAXES	(9,329)	11,729	(6,552)	22,901
NET INCOME	$ 8,169	$ 4,056	$ 10,521	$ 18,530
Net income per share (Note 8):
Basic (in dollars per share)	$ 0.05	$ 0.02	$ 0.06	$ 0.11
Diluted (in dollars per share)	$ 0.05	$ 0.02	$ 0.06	$ 0.11
Weighted-average shares outstanding:
Basic (in shares)	171,648	164,294	169,898	163,289
Diluted (in shares)	177,897	169,727	175,963	168,735

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 8,169	$ 4,056	$ 10,521	$ 18,530
Other comprehensive income (loss)—net of taxes:
Foreign currency translation losses	0	(432)	0	(333)
Unrealized gains (losses) on investments	337	(977)	400	(993)
Tax benefit (provision) related to items of other comprehensive income or loss	(118)	342	(141)	348
Other comprehensive income (loss)—net of taxes	219	(1,067)	259	(978)
Comprehensive income	$ 8,388	$ 2,989	$ 10,780	$ 17,552

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 10,521	$ 18,530
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	22,206	16,519
Amortization of investment premiums	5,770	6,680
Stock-based compensation	67,001	42,313
Excess tax benefit from stock-based compensation	0	(4,325)
Other non-cash items—net	2,681	3,801
Changes in operating assets and liabilities, net of assets acquired and liabilities assumed in business acquisitions:
Accounts receivable—net	20,923	13,140
Inventory	(12,427)	(11,095)
Deferred tax assets	(28,297)	(12,186)
Prepaid expenses and other current assets	(7,806)	(2,781)
Other assets	(264)	(159)
Accounts payable	(9,842)	3,806
Accrued liabilities	(3,296)	2,818
Accrued payroll and compensation	(1,895)	5,651
Other liabilities	(1,232)	14,350
Deferred revenue	136,193	68,006
Income taxes payable	13,753	(3,850)
Net cash provided by operating activities	213,989	161,218
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of investments	(329,687)	(388,808)
Sales of investments	35,384	27,282
Maturities of investments	364,256	371,837
Purchases of property and equipment	(29,013)	(26,802)
Payments made in connection with business acquisitions—net of cash acquired	(38,025)	(17)
Net cash provided by (used in) investing activities	2,915	(16,508)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock	63,543	40,529
Taxes paid related to net share settlement of equity awards	(22,989)	(8,506)
Excess tax benefit from stock-based compensation	0	4,325
Repurchase and retirement of common stock	0	(38,235)
Net cash provided by (used in) financing activities	40,554	(1,887)
EFFECT OF EXCHANGE RATES ON CASH AND CASH EQUIVALENTS	0	(600)
NET INCREASE IN CASH AND CASH EQUIVALENTS	257,458	142,223
CASH AND CASH EQUIVALENTS—Beginning of period	283,254	115,873
CASH AND CASH EQUIVALENTS—End of period	540,712	258,096
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Cash paid for income taxes—net	15,272	38,755
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Transfers of evaluation units from inventory to property and equipment	13,695	9,073
Liability for purchase of property and equipment and asset retirement obligations	2,243	4,710
Liability incurred for repurchase of common stock	0	379
Equity awards assumed in connection with business acquisition	$ 471	$ 0

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 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 and nine months ended September 30, 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. 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 was not material for 2014 or any of our previously issued financial statements. There have been no material changes to our significant accounting policies as of and for the three and nine months ended September 30, 2015 , except for the inclusion of policies related to business combinations and restructuring charges. Business combinations —We include the results of operations of the businesses that we acquire as of the respective dates of acquisition. We allocate the fair value of the purchase price of our business acquisitions to the tangible assets acquired, liabilities assumed, and intangible assets acquired, based on their estimated fair values. The excess of the purchase price over the fair values of these identifiable assets and liabilities is recorded as goodwill. Additional information existing as of the acquisition date but unknown to us may become known during the remainder of the measurement period, not to exceed 12 months from the acquisition date, which may result in changes to the amounts and allocations recorded. Restructuring charges —We recognize liability for exit and disposal activities when the liability is incurred. Our restructuring charges consist of one-time termination benefits related to the reduction of our workforce, contract-termination costs, such as lease exit costs, and other costs. Liabilities for costs associated with a restructuring activity are measured at fair value and are recognized when the liability is incurred. One-time termination benefits are expensed at the date we notify the employee, unless the employee must provide future service, in which case the benefits are expensed ratably over the future service period. A liability for contract-termination costs represents a liability for costs to terminate a contract before the end of its term and is recognized at fair value when we terminate the contract in accordance with the contract terms, which is usually done by giving written notice to the counterparty within the notification period specified by the contract or by otherwise negotiating a termination with the counterparty. A liability for costs that will continue to be incurred under a contract for its remaining term without economic benefit to the entity is recognized at the cease-use date. Costs to terminate a lease before the end of its term are recognized when the property is vacated. Other costs primarily consist of asset write-offs and consulting fees, which are expensed when incurred. We continually evaluate the adequacy of the remaining liabilities under our restructuring initiatives. Although we believe that these estimates accurately reflect the costs of our restructuring plans, actual results may differ and thereby require us to record an additional provision or reverse a portion of such a provision. Recent Accounting Pronouncements In September 2015, the Financial Accounting Standards Board (“FASB“) issued Accounting Standards Update 2015-16—Simplifying the Accounting for Measurement-Period Adjustments (“ASU 2015-16”). ASU 2015-16 eliminates the requirement for an acquirer in a business combination to account for measurement-period adjustments retrospectively. Instead, acquirers must recognize measurement-period adjustments during the period in which they determine the amounts, including the effect on earnings of any amounts they would have recorded in previous periods if the accounting had been completed at the acquisition date. ASU 2015-16 will be effective for us beginning on January 1, 2016. In July 2015, the FASB issued Accounting Standards Update 2015-11—Inventory—Simplifying the Measurement of Inventory (Topic 330) (“ASU 2015-11”). ASU 2015-11 changes the measurement principle for inventory from the lower of cost or market to lower of cost and net realizable value. It applies to entities that measure inventory using a method other than last-in, first-out or the retail inventory method (e.g., first-in first-out, average cost). ASU 2015-11 will be effective for us beginning on January 1, 2017. We do not expect the impact of ASU 2015-11 on our consolidated financial statements to be significant. In May 2014, the FASB 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. In July 2015, the FASB decided to delay the effective date of the new revenue standard by one year. As such, ASU 2014-09 will be effective for us beginning on January 1, 2018, with the option to adopt earlier on January 1, 2017. We are currently evaluating the impact of ASU 2014-09 on our consolidated financial statements.

Financial Instruments and Fair

Financial Instruments and Fair Value Measurements	9 Months Ended
	Sep. 30, 2015
Financial Instruments and Fair Value [Abstract]
FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS	FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS The following table summarizes our investments as of September 30, 2015 and December 31, 2014 (in thousands): September 30, 2015 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Corporate debt securities $ 485,236 $ 265 $ (470 ) $ 485,031 Commercial paper 59,936 6 (10 ) 59,932 Municipal bonds 59,251 71 (7 ) 59,315 Certificates of deposit and term deposits (1) 8,668 — — 8,668 U.S. government and agency securities 16,001 5 — 16,006 Total available-for-sale securities $ 629,092 $ 347 $ (487 ) $ 628,952 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. 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 September 30, 2015 and December 31, 2014 (in thousands): September 30, 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 $ 217,790 $ (370 ) $ 37,622 $ (100 ) $ 255,412 $ (470 ) Commercial paper 16,720 (10 ) — — 16,720 (10 ) Municipal bonds 10,302 (4 ) 1,012 (3 ) 11,314 (7 ) Total available-for-sale securities $ 244,812 $ (384 ) $ 38,634 $ (103 ) $ 283,446 $ (487 ) 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 September 30, 2015 and December 31, 2014 were as follows (in thousands): September 30, December 31, Due within one year $ 367,446 $ 436,766 Due within one to three years 261,506 271,724 Total $ 628,952 $ 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 September 30, 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 Measured at Fair Value on a Recurring Basis The following table presents the fair value of our financial assets measured at fair value on a recurring basis as of September 30, 2015 and December 31, 2014 (in thousands): September 30, 2015 December 31, 2014 Aggregate Fair Value Quoted Prices in Active Markets For Identical Assets Significant Other Observable Inputs Aggregate Fair Value Quoted Prices in Active Markets For Identical Assets Significant Other Observable Inputs (Level 1) (Level 2) (Level 1) (Level 2) Assets: Corporate debt securities $ 485,031 $ — $ 485,031 $ 589,016 $ — $ 589,016 Commercial paper 61,932 — 61,932 51,155 — 51,155 Municipal bonds 59,315 — 59,315 39,721 — 39,721 Certificates of deposit and term deposits 8,668 — 8,668 22,854 — 22,854 Money market funds 81,683 81,683 — 13,311 13,311 — U.S. government and agency securities 16,006 2,002 14,004 5,744 1,998 3,746 Total $ 712,635 $ 83,685 $ 628,950 $ 721,801 $ 15,309 $ 706,492 Reported as: Cash equivalents $ 83,683 $ 13,311 Short-term investments 367,446 436,766 Long-term investments 261,506 271,724 Total $ 712,635 $ 721,801 There were no transfers between Level 1 and Level 2 of the fair value hierarchy during the period ended September 30, 2015 .

Inventory

Inventory	9 Months Ended
	Sep. 30, 2015
Inventory Disclosure [Abstract]
INVENTORY	INVENTORY Inventory consisted of the following as of September 30, 2015 and December 31, 2014 (in thousands): September 30, December 31, Raw materials $ 13,594 $ 10,617 Finished goods 67,056 58,860 Total inventory $ 80,650 $ 69,477 Inventory includes finished goods held by distributors where revenue is recognized on a sell-through basis of $1.5 million and $1.2 million as of September 30, 2015 and December 31, 2014, respectively. Inventory also includes raw materials at contract manufacturers of $4.2 million and $4.8 million as of September 30, 2015 and December 31, 2014, respectively.

Property and Equipment_Net

Property and Equipment—Net	9 Months Ended
	Sep. 30, 2015
Property, Plant and Equipment [Abstract]
PROPERTY AND EQUIPMENT—Net	PROPERTY AND EQUIPMENT—net Property and equipment—net consisted of the following as of September 30, 2015 and December 31, 2014 (in thousands): September 30, December 31, Land $ 21,685 $ 13,895 Building and building improvements 22,283 20,166 Evaluation units 40,984 31,474 Computer equipment and software 43,658 31,821 Furniture and fixtures 7,054 5,096 Construction-in-progress 10,248 3,902 Leasehold improvements 9,070 7,998 Total property and equipment 154,982 114,352 Less: accumulated depreciation (71,610 ) (55,433 ) Property and equipment—net $ 83,372 $ 58,919 Depreciation expense was $7.5 million and $5.4 million during the three months ended September 30, 2015 and September 30, 2014 , respectively. Depreciation expense was $20.3 million and $15.3 million during the nine months ended September 30, 2015 and September 30, 2014 , respectively.

Investments in Privately-Held C

Investments in Privately-Held Companies	9 Months Ended
	Sep. 30, 2015
Investments, All Other Investments [Abstract]
INVESTMENTS IN PRIVATELY-HELD COMPANIES	INVESTMENTS IN PRIVATELY-HELD COMPANIES As of September 30, 2015 , we had invested a total of $10.3 million in the equity securities of three privately-held companies. Each of these investments is accounted for as a cost-basis investment, 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 existed. During the nine months ended September 30, 2015 , no events have occurred that would adversely affect the carrying value of these investments.

Business Combinations

Business Combinations	9 Months Ended
	Sep. 30, 2015
Business Combinations [Abstract]
BUSINESS COMBINATIONS	BUSINESS COMBINATIONS On July 8, 2015, we completed our previously announced acquisition of all of the outstanding shares of Meru Networks, Inc. (“Meru”). Meru is a provider of Wi-Fi networking products and services. With this acquisition, we expand on our secure wireless vision and enterprise growth focus, broaden our solutions portfolio, and enhance our opportunity to address the global enterprise Wi-Fi market with integrated and intelligent secure wireless solutions. In connection with the acquisition, we paid total cash consideration of $40.9 million and incurred $0.4 million of withholding tax liability. In addition, all of the outstanding restricted stock units (“RSUs”) of Meru were converted into RSUs for 53,401 shares of our common stock. The cash payment, along with the estimated fair value of the earned RSUs assumed, resulted in a purchase price of $41.8 million . The total purchase price was as follows (in thousands): Purchase Price: Cash $ 40,914 Estimated fair value of shares withheld for taxes 379 Estimated fair value of earned equity awards assumed by Fortinet 471 Total purchase price $ 41,764 We accounted for this transaction as a business combination. We expensed acquisition-related costs of $1.7 million in general and administrative expenses. The total purchase price was allocated to Meru’s identifiable tangible and intangible assets acquired and liabilities assumed based on their estimated fair values as of the acquisition date. The total purchase price was allocated using the information currently available. As a result, we may continue to adjust the estimated purchase price allocation as and when additional information is available. Total allocation of the purchase price was as follows (in thousands): Cash and cash equivalents $ 3,268 Accounts receivable 8,316 Inventory 11,854 Prepaid expenses and other assets 2,409 Property and equipment 983 Deferred tax assets 18,585 Identifiable intangible assets 19,600 Goodwill 1,436 Total assets acquired 66,451 Deferred revenue 9,800 Accounts payable and accrued liabilities 14,887 Total liabilities assumed 24,687 Total purchase price allocation $ 41,764 The goodwill of $1.4 million represents the premium we paid over the fair value of the net tangible liabilities assumed and identified intangible assets acquired, due primarily to Meru’s assembled workforce. The goodwill recorded as part of the Meru acquisition is not deductible for U.S. federal income tax purposes. Intangible assets consist primarily of customer relationships and developed technologies. Customer relationships represent Meru’s installed base and the ability to sell existing, in-process and future versions of our products and services to its existing customers. Developed technologies represent the virtualized wireless local area network solutions offering centralized coordination and control of various access points on the network. This includes patented and unpatented technology, know-how, processes, designs and computer software. The estimated useful life and fair values of the acquired identifiable intangible assets were as follows (in thousands, except for estimated useful life): Estimated Useful Life (in years) Fair Values Customer relationships 5 $ 12,200 Developed technologies 4 7,200 Trade name 0.5 200 Total $ 19,600 The amortization expense of customer relationships and trade name is amortized on a straight-line basis and is recorded in sales and marketing expenses. The amortization expense of developed technologies is amortized on a straight-line basis and is recorded in cost of product revenue. Upon acquisition, Meru became our wholly-owned subsidiary. The results of operations of Meru have been included in our consolidated statements of operations from the acquisition date. Revenue and net loss of Meru from July 8, 2015 through September 30, 2015 were $12.0 million and $9.6 million , respectively. The unaudited financial information below summarizes the combined results of Fortinet and Meru on a pro forma basis, after giving effect to the acquisition of Meru on July 8, 2015, as though the business combination occurred on January 1, 2014. The pro forma financial information is presented for informational purposes and is not indicative of the results of operations that would have been achieved if the acquisition had taken place at the beginning of each of the periods presented. The following pro forma financial information for all periods presented includes purchase accounting adjustments for amortization charges from acquired intangible assets, depreciation of acquired property, plant and equipment, stock-based compensation and related tax effects (in thousands): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Pro forma revenue $ 261,199 $ 218,363 $ 750,442 $ 615,581 Pro forma income (loss) from operations $ (5,968 ) $ 11,194 $ (15,368 ) $ 20,768 Pro forma net income (loss) $ 4,959 $ 572 $ (2,619 ) $ 4,173 Pro forma net income (loss) per basic $ 0.03 $ — $ (0.02 ) $ 0.03 Pro forma net income (loss) per diluted $ 0.03 $ — $ (0.01 ) $ 0.02

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets - Net	9 Months Ended
	Sep. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND OTHER INTANGIBLE ASSETS - NET	GOODWILL AND OTHER INTANGIBLE ASSETS—net Goodwill There were no impairments to goodwill during the three and nine months ended September 30, 2015. The following table presents the changes in the carrying amount of goodwill (in thousands): Amount Balance—December 31, 2014 $ 2,824 Addition due to business acquisition 1,436 Balance—September 30, 2015 $ 4,260 Other Intangible Assets—net During the three months ended June 30, 2015, we reassessed the fair value and the remaining useful life of the developed technologies and customer relationship acquired from the Coyote Point business acquisition. Based on this reassessment, we determined a decrease in the projected cash flow and that the remaining net book value of the developed technologies and customer relationships were impaired. As a result, we recorded an impairment charge of $1.6 million associated with these assets. The impairment charge is included within cost of product revenue and sales and marketing in the condensed consolidated statements of operations. The following tables present other intangible assets—net (in thousands): September 30, 2015 Weighted Average Useful Life (in years) Gross Accumulated Amortization Net Other intangible assets—net: Customer relationships 5.0 $ 12,200 $ 610 $ 11,590 Developed technologies 3.6 11,184 3,907 7,277 Trade names 0.5 200 100 100 Total other intangible assets—net $ 23,584 $ 4,617 $ 18,967 December 31, 2014 Weighted Average Useful Life (in years) Gross Accumulated Amortization Net Other intangible assets—net: Developed technologies 3.6 $ 5,606 $ 3,128 $ 2,478 Customer relationships 6.0 500 146 354 Total other intangible assets—net $ 6,106 $ 3,274 $ 2,832 Amortization expense was $1.3 million and $0.2 million for the three months ended September 30, 2015 and September 30, 2014, respectively. Amortization expense was $1.9 million and $1.2 million for the nine months ended September 30, 2015 and September 30, 2014, respectively. The following table summarizes estimated future amortization expense of other intangible assets—net (in thousands): Amount 2015 (remainder) $ 1,327 2016 4,600 2017 4,240 2018 4,240 2019 3,340 Thereafter 1,220 Total $ 18,967

Net Income Per Share

Net Income Per Share	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
NET INCOME PER SHARE	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, 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 Nine Months Ended September 30, September 30, September 30, September 30, Numerator: Net income $ 8,169 $ 4,056 $ 10,521 $ 18,530 Denominator: Basic shares: Weighted-average common stock outstanding—basic 171,648 164,294 169,898 163,289 Diluted shares: Weighted-average common stock outstanding—basic 171,648 164,294 169,898 163,289 Effect of potentially dilutive securities: Stock options 3,451 4,405 3,669 4,728 RSUs (including PSUs) 2,742 993 2,335 692 ESPP 56 35 61 26 Weighted-average shares used to compute diluted net income per share 177,897 169,727 175,963 168,735 Net income per share: Basic $ 0.05 $ 0.02 $ 0.06 $ 0.11 Diluted $ 0.05 $ 0.02 $ 0.06 $ 0.11 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 Nine Months Ended September 30, September 30, September 30, September 30, Stock options 265 3,023 271 4,101 RSUs (including PSUs) 1,331 696 1,026 879 ESPP 209 226 126 133 1,805 3,945 1,423 5,113

Deferred Revenue

Deferred Revenue	9 Months Ended
	Sep. 30, 2015
Deferred Revenue Disclosure [Abstract]
DEFERRED REVENUE	DEFERRED REVENUE Deferred revenue consisted of the following as of September 30, 2015 and December 31, 2014 (in thousands): September 30, December 31, Product $ 6,134 $ 4,642 Service 700,777 554,115 Total deferred revenue $ 706,911 $ 558,757 Reported as: Current $ 471,118 $ 368,929 Non-current 235,793 189,828 Total deferred revenue $ 706,911 $ 558,757

Restructuring Charges

Restructuring Charges	9 Months Ended
	Sep. 30, 2015
Restructuring and Related Activities [Abstract]
RESTRUCTURING CHARGES	RESTRUCTURING CHARGES In connection with the acquisition of Meru, during the third quarter of 2015, we initiated planned cost reduction and restructuring activities to improve our cost structure and operational efficiencies. We estimate that we will incur $6.3 million of restructuring charges, consisting of severance and other one-time benefits, contract terminations and other charges. We incurred $5.9 million of restructuring charges during the three months ended September 30, 2015 which are included in operating expense in the condensed consolidated statements of operations. These charges are primarily related to severance and other one-time benefits to be paid in cash. We expect the remainder of the amount to be incurred during the fourth quarter of 2015 and in 2016. The following table provides a summary of restructuring activity as of September 30, 2015 (in thousands): Employee Severance and Other Benefits Contract Terminations and Other Charges Total Balance as of December 31, 2014 $ — $ — $ — Costs incurred 5,469 414 5,883 Less cash payments (1,858 ) (62 ) (1,920 ) Less non-cash charges (219 ) (191 ) (410 ) Balance as of September 30, 2015 $ 3,392 $ 161 $ 3,553 Cash payments for the restructuring activities are expected to be made through fiscal year 2017, primarily relating to severance and other one-time benefits. The short-term portion of the restructuring reserve of $2.7 million is included in accrued liabilities and the remaining long-term portion of $0.9 million is included in other liabilities on the condensed balance sheet as of September 30, 2015.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES The following table summarizes our future principal contractual obligations as of September 30, 2015 (in thousands): Total 2015 (remainder) 2016 2017 2018 2019 Thereafter Operating lease commitments $ 56,775 $ 4,167 $ 15,679 $ 10,879 $ 8,404 $ 7,053 $ 10,593 Inventory purchase commitments 75,984 73,038 2,946 — — — — Other contractual commitments and open purchase orders 38,072 26,233 7,995 2,149 751 609 335 Total $ 170,831 $ 103,438 $ 26,620 $ 13,028 $ 9,155 $ 7,662 $ 10,928 Operating Leases —We lease certain facilities under various non-cancelable operating leases, which expire through 2025. 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 $3.7 million and $2.6 million during the three months ended September 30, 2015 and 2014, respectively. Rent expense was $9.7 million and $7.7 million during the nine months ended September 30, 2015 and 2014, respectively. Rent expense is recognized using the straight-line method over the term of the lease. Inventory Purchase —Our independent contract manufacturers procure certain inventory items 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 September 30, 2015 , we had $76.0 million of open purchase orders with our independent contract manufacturers. Other Contractual Commitments and Open Purchase Orders —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 September 30, 2015 , we had $38.1 million in other contractual commitments and open purchase orders. Warranties —Accrued warranty activities are summarized as follows (in thousands): Nine Months Ended September 30, September 30, Accrued warranty balance—beginning of the period $ 4,269 $ 3,037 Warranty costs incurred (3,413 ) (2,597 ) Provision for warranty for the period, including warranty liabilities assumed in connection with a business acquisition 3,638 3,786 Adjustment related to pre-existing warranties (94 ) (540 ) Accrued warranty balance—end of the period $ 4,400 $ 3,686 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 a significant 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. In some contracts, our exposure under these indemnification provisions is limited by the terms of the contracts to certain defined limits, such as the total amount paid by our customer under the agreement. However, certain agreements include covenants, penalties 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.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
STOCKHOLDERS' EQUITY	STOCKHOLDERS’ EQUITY Stock-Based Compensation Plans Our stock-based compensation plans include the 2000 Stock Plan (the “2000 Plan”), the 2008 Stock Plan (the “2008 Plan”), the 2009 Equity Incentive Plan (the “2009 Plan”), 2011 Employee Stock Purchase Plan (the “ESPP”) and equity plans assumed through the Meru acquisition. Under these plans, we have granted (or, in the case of acquired plans, assumed) stock options and RSUs, including PSUs. In connection with the Meru acquisition, we assumed and exchanged Meru’s outstanding RSUs with an estimated fair value of $2.0 million . Of the total estimated fair value, $0.5 million relating to earned equity awards was allocated to the purchase price and the remainder relating to future services is being recognized over the remaining service period. No new equity awards can be granted under the assumed plans. As of September 30, 2015, RSUs representing 42,332 shares of common stock were outstanding under the awards assumed through the acquisition of Meru. As of September 30, 2015 , there were a total of 41,362,003 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 Nine Months Ended September 30, September 30, September 30, September 30, Expected term in years 4.3 4.9 4.3 4.9 Volatility 37 % 41 % 38 % 43 % Risk-free interest rate 1.6 % 1.6 % 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 656 41.02 Forfeited (123 ) 26.69 Exercised (4,016 ) 11.38 Balance—September 30, 2015 7,219 $ 19.16 Options vested and expected to vest—September 30, 2015 7,155 $ 18.97 2.8 $ 169,925 Options exercisable—September 30, 2015 6,021 $ 16.40 2.2 $ 157,064 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 September 30, 2015 , for all in-the-money options. As of September 30, 2015 , total compensation expense related to unvested stock options granted to employees but not yet recognized was $14.0 million . This expense is expected to be amortized on a straight-line basis over a weighted-average period of 2.6 years. Additional information related to our stock options is summarized below (in thousands, except per share amounts): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Weighted-average fair value per share granted $ 15.89 $ 9.13 $ 13.60 $ 8.76 Intrinsic value of options exercised 40,132 17,728 103,170 49,490 Fair value of options vested 2,491 4,393 9,001 13,163 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 and assumed through business acquisition 5,385 40.01 Forfeited (675 ) 27.80 Vested (1,776 ) 22.35 Balance—September 30, 2015 9,225 $ 32.66 RSUs expected to vest—September 30, 2015 7,899 $ 32.90 As of September 30, 2015 , total compensation expense related to unvested RSUs that were granted to employees and non-employees, but not yet recognized, was $291.4 million . 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 Nine Months Ended September 30, September 30, September 30, September 30, Shares withheld for taxes 245 124 590 381 Amount withheld for taxes $ 11,628 $ 2,985 $ 22,989 $ 8,506 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 our employees who are not executive officers 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 such 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. There were no PSUs granted during the three months ended September 30, 2015 and September 30, 2014. The following table summarizes the weighted-average assumptions relating to our PSUs granted to our executive officers: Nine Months Ended September 30, September 30, Expected term in years 3.0 3.0 Volatility 38 % 47 % Risk-free interest rate 1.1 % 0.9 % Dividend rate — % — % The following table summarizes the activity and related information for PSUs for the periods presented below (in thousands, except per share amounts): Nine Months Ended September 30, September 30, Shares granted to executive officers and employees 206 120 Weighted-average fair value per share granted $ 34.86 $ 21.21 As of September 30, 2015 , total compensation expense related to unvested PSUs that were granted to certain of our executive officers and employees, but not yet recognized, was $6.4 million . This expense is expected to be amortized on a straight-line basis over a weighted-average vesting period of 2.1 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 Nine Months Ended September 30, September 30, September 30, September 30, Expected term in years 0.5 0.5 0.5 0.5 Volatility 32 % 32 % 31 % 34 % Risk-free interest rate 0.2 % 0.1 % 0.1 % 0.1 % Dividend rate — % — % — % — % Additional information related to the ESPP is provided below (in thousands, except per share amounts): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Weighted-average fair value per share granted $ 11.42 $ 6.03 $ 8.23 $ 5.91 Shares issued under the ESPP 337 346 764 770 Weighted-average price per share issued $ 28.05 $ 19.38 $ 24.30 $ 18.17 Stock-based Compensation Expense Stock-based compensation expense is included in costs and expenses as follows (in thousands): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Cost of product revenue $ 291 $ 60 $ 641 $ 351 Cost of service revenue 1,849 1,522 5,141 4,214 Research and development 6,663 4,505 17,361 12,558 Sales and marketing 13,904 7,397 34,482 18,890 General and administrative 3,612 1,183 9,376 6,300 Total stock-based compensation expense $ 26,319 $ 14,667 $ 67,001 $ 42,313 The following table summarizes stock-based compensation expense by award type (in thousands): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Stock options $ 2,669 $ 4,282 $ 9,141 $ 13,395 RSUs (including PSUs) 21,996 9,275 53,674 25,886 ESPP 1,654 1,110 4,186 3,032 Total stock-based compensation expense $ 26,319 $ 14,667 $ 67,001 $ 42,313 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 Nine Months Ended September 30, September 30, September 30, September 30, Income tax benefit associated with stock-based compensation $ 5,224 $ 4,225 $ 12,867 $ 11,821 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 and nine months ended September 30, 2015 , there were no shares repurchased under the Program. As of September 30, 2015 , $122.5 million remains available for future share repurchases under the Program.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2015
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES We recognized a tax benefit of $9.3 million and a tax expense of $11.7 million on pretax net loss of $1.2 million and pretax net income of $15.8 million during the three months ended September 30, 2015 and 2014, respectively. The effective tax rate was 804% for the three months ended September 30, 2015 , compared to an effective tax rate of 74% for the same period last year. The effective tax rate was a benefit of 165% for the nine months ended September 30, 2015 , compared to an effective tax rate of 55% for the same period last year. The benefit 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. The decrease in the tax provision and change in effective tax rate was primarily due to the decrease in profitability before income taxes and additional tax benefits related to discrete items, such as the increase of the prior year's federal research and development credit and the release of previously unrecognized tax benefits. The effective tax rate for the three months ended September 30, 2015 also reflected a tax benefit due to a recent U.S. Tax Court opinion based on which we recognized the tax benefit due to the exclusion of the stock-based compensation from intercompany charges in prior periods. As of September 30, 2015 and December 31, 2014, unrecognized tax benefits were $55.8 million and $44.2 million , respectively. The total amount of $54.6 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 September 30, 2015 , we had accrued $5.0 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 tax authorities for tax years prior to 2011, and we are currently subject to examination by U.S federal income tax authorities for tax year 2012.

Defined Contribution Plans

Defined Contribution Plans	9 Months Ended
	Sep. 30, 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) Plan and RRSP during the three months ended September 30, 2015 and September 30, 2014 were $0.9 million and $0.7 million , respectively. Our matching contributions to the 401(k) Plan and RRSP during the nine months ended September 30, 2015 and September 30, 2014 were $2.7 million and $1.9 million , respectively.

Segment and Significant Custome

Segment and Significant Customer Information	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
SEGMENT AND SIGNIFICANT CUSTOMER INFORMATION	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 Nine Months Ended Revenue September 30, September 30, September 30, September 30, Americas: United States $ 72,767 $ 50,329 $ 202,491 $ 144,794 Canada 26,027 21,104 72,676 59,837 Other Americas 14,371 10,785 38,151 28,404 Total Americas 113,165 82,218 313,318 233,035 Europe, Middle East, and Africa (“EMEA”) 91,740 66,157 250,808 185,354 Asia Pacific (“APAC”) 55,163 44,973 148,613 128,006 Total revenue $ 260,068 $ 193,348 $ 712,739 $ 546,395 The following table sets forth property and equipment by geographic region as of September 30, 2015 and December 31, 2014 (in thousands): Property and Equipment — net September 30, December 31, Americas: United States $ 58,372 $ 46,116 Canada 7,811 6,054 Other Americas 1,853 875 Total Americas 68,036 53,045 EMEA: France 9,369 2,052 Other EMEA 2,236 1,204 Total EMEA 11,605 3,256 APAC 3,731 2,618 Total property and equipment—net $ 83,372 $ 58,919 The following customers, each of which is a distributor, accounted for 10% or more of our revenue: Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Exclusive Networks Group 17 % 15 % 17 % 14 % Fin Tec Computers * 11 % * * * Represents less than 10% The following customers, each of which is a distributor, accounted for 10% or more of net accounts receivable: September 30, December 31, Exclusive Networks Group 19 % 18 % Ingram Micro 11 % * Fin Tec Computer 10 % * * Represents less than 10%

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	9 Months Ended
	Sep. 30, 2015
Other Comprehensive Income (Loss), Net of Tax [Abstract]
ACCUMULATED OTHER COMPREHENSIVE LOSS	ACCUMULATED OTHER COMPREHENSIVE LOSS The following table summarizes the changes in accumulated balances of other comprehensive loss (in thousands): Unrealized Gains (Losses) on Investments Tax benefit (provision) related to items of other comprehensive income or loss Total Beginning balance as of December 31, 2014 $ (540 ) $ 191 $ (349 ) Other comprehensive income before reclassifications 407 (143 ) 264 Amounts reclassified from accumulated other comprehensive loss (7 ) 2 (5 ) Net current-period other comprehensive income 400 (141 ) 259 Ending balance as of September 30, 2015 $ (140 ) $ 50 $ (90 ) The following table provides details about the reclassification out of accumulated other comprehensive loss (in thousands): Nine Months Ended September 30, 2015 Details about Accumulated Other Comprehensive Loss Components Amount Reclassified from Accumulated Other Comprehensive Loss Affected Line Item in the Statement Where Net Income is Presented Unrealized gains on investments $ (7 ) Other expense—net Tax provision related to items of other comprehensive income 2 Provision for (benefit from)income taxes Total reclassification for the period $ (5 )

Foreign Currency Derivatives

Foreign Currency Derivatives	9 Months Ended
	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
FOREIGN CURRENCY DERIVATIVES	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” ), the Euro ( “ EUR ” ), and the British Pound ( “ GBP ”) . 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 EUR and GBP could adversely impact our operating expenses in the future. The notional amount of our forward exchange contract to hedge balance sheet accounts were (in thousands): Buy/Sell Notional Currency—As of September 30, 2015 CAD Sell $ 9,653 Currency—As of December 31, 2014 CAD Buy $ 6,879 As of September 30, 2015, the fair value of the forward exchange contract was not material.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2015
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	RELATED PARTY TRANSACTIONS The son of one member of our Board of Directors (“Board”) is a partner in 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 $0.9 million each for the three months ended September 30, 2015 and September 30, 2014 , respectively. Expenses for legal services provided by the law firm related to matters that arose subsequent to the member joining our Board were $3.7 million and $1.7 million for the nine months ended September 30, 2015 and September 30, 2014 , respectively. Amounts due and payable to the law firm were $1.4 million and $1.3 million as of September 30, 2015 and December 31, 2014, respectively.

Summary of Significant Accoun25

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 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 and nine months ended September 30, 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 was not material for 2014 or any of our previously issued financial statements.
Business Combinations	Business combinations —We include the results of operations of the businesses that we acquire as of the respective dates of acquisition. We allocate the fair value of the purchase price of our business acquisitions to the tangible assets acquired, liabilities assumed, and intangible assets acquired, based on their estimated fair values. The excess of the purchase price over the fair values of these identifiable assets and liabilities is recorded as goodwill. Additional information existing as of the acquisition date but unknown to us may become known during the remainder of the measurement period, not to exceed 12 months from the acquisition date, which may result in changes to the amounts and allocations recorded.
Restructuring Charges	Restructuring charges —We recognize liability for exit and disposal activities when the liability is incurred. Our restructuring charges consist of one-time termination benefits related to the reduction of our workforce, contract-termination costs, such as lease exit costs, and other costs. Liabilities for costs associated with a restructuring activity are measured at fair value and are recognized when the liability is incurred. One-time termination benefits are expensed at the date we notify the employee, unless the employee must provide future service, in which case the benefits are expensed ratably over the future service period. A liability for contract-termination costs represents a liability for costs to terminate a contract before the end of its term and is recognized at fair value when we terminate the contract in accordance with the contract terms, which is usually done by giving written notice to the counterparty within the notification period specified by the contract or by otherwise negotiating a termination with the counterparty. A liability for costs that will continue to be incurred under a contract for its remaining term without economic benefit to the entity is recognized at the cease-use date. Costs to terminate a lease before the end of its term are recognized when the property is vacated. Other costs primarily consist of asset write-offs and consulting fees, which are expensed when incurred. We continually evaluate the adequacy of the remaining liabilities under our restructuring initiatives. Although we believe that these estimates accurately reflect the costs of our restructuring plans, actual results may differ and thereby require us to record an additional provision or reverse a portion of such a provision.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In September 2015, the Financial Accounting Standards Board (“FASB“) issued Accounting Standards Update 2015-16—Simplifying the Accounting for Measurement-Period Adjustments (“ASU 2015-16”). ASU 2015-16 eliminates the requirement for an acquirer in a business combination to account for measurement-period adjustments retrospectively. Instead, acquirers must recognize measurement-period adjustments during the period in which they determine the amounts, including the effect on earnings of any amounts they would have recorded in previous periods if the accounting had been completed at the acquisition date. ASU 2015-16 will be effective for us beginning on January 1, 2016. In July 2015, the FASB issued Accounting Standards Update 2015-11—Inventory—Simplifying the Measurement of Inventory (Topic 330) (“ASU 2015-11”). ASU 2015-11 changes the measurement principle for inventory from the lower of cost or market to lower of cost and net realizable value. It applies to entities that measure inventory using a method other than last-in, first-out or the retail inventory method (e.g., first-in first-out, average cost). ASU 2015-11 will be effective for us beginning on January 1, 2017. We do not expect the impact of ASU 2015-11 on our consolidated financial statements to be significant. In May 2014, the FASB 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. In July 2015, the FASB decided to delay the effective date of the new revenue standard by one year. As such, ASU 2014-09 will be effective for us beginning on January 1, 2018, with the option to adopt earlier on January 1, 2017. We are currently evaluating the impact of ASU 2014-09 on our consolidated financial statements.

Financial Instruments and Fai26

Financial Instruments and Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2015
Financial Instruments and Fair Value [Abstract]
Summary of Investments	The following table summarizes our investments as of September 30, 2015 and December 31, 2014 (in thousands): September 30, 2015 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Corporate debt securities $ 485,236 $ 265 $ (470 ) $ 485,031 Commercial paper 59,936 6 (10 ) 59,932 Municipal bonds 59,251 71 (7 ) 59,315 Certificates of deposit and term deposits (1) 8,668 — — 8,668 U.S. government and agency securities 16,001 5 — 16,006 Total available-for-sale securities $ 629,092 $ 347 $ (487 ) $ 628,952 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	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 September 30, 2015 and December 31, 2014 (in thousands): September 30, 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 $ 217,790 $ (370 ) $ 37,622 $ (100 ) $ 255,412 $ (470 ) Commercial paper 16,720 (10 ) — — 16,720 (10 ) Municipal bonds 10,302 (4 ) 1,012 (3 ) 11,314 (7 ) Total available-for-sale securities $ 244,812 $ (384 ) $ 38,634 $ (103 ) $ 283,446 $ (487 ) 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	The contractual maturities of our investments as of September 30, 2015 and December 31, 2014 were as follows (in thousands): September 30, December 31, Due within one year $ 367,446 $ 436,766 Due within one to three years 261,506 271,724 Total $ 628,952 $ 708,490
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following table presents the fair value of our financial assets measured at fair value on a recurring basis as of September 30, 2015 and December 31, 2014 (in thousands): September 30, 2015 December 31, 2014 Aggregate Fair Value Quoted Prices in Active Markets For Identical Assets Significant Other Observable Inputs Aggregate Fair Value Quoted Prices in Active Markets For Identical Assets Significant Other Observable Inputs (Level 1) (Level 2) (Level 1) (Level 2) Assets: Corporate debt securities $ 485,031 $ — $ 485,031 $ 589,016 $ — $ 589,016 Commercial paper 61,932 — 61,932 51,155 — 51,155 Municipal bonds 59,315 — 59,315 39,721 — 39,721 Certificates of deposit and term deposits 8,668 — 8,668 22,854 — 22,854 Money market funds 81,683 81,683 — 13,311 13,311 — U.S. government and agency securities 16,006 2,002 14,004 5,744 1,998 3,746 Total $ 712,635 $ 83,685 $ 628,950 $ 721,801 $ 15,309 $ 706,492 Reported as: Cash equivalents $ 83,683 $ 13,311 Short-term investments 367,446 436,766 Long-term investments 261,506 271,724 Total $ 712,635 $ 721,801

Inventory (Tables)

Inventory (Tables)	9 Months Ended
	Sep. 30, 2015
Inventory Disclosure [Abstract]
Inventory	Inventory consisted of the following as of September 30, 2015 and December 31, 2014 (in thousands): September 30, December 31, Raw materials $ 13,594 $ 10,617 Finished goods 67,056 58,860 Total inventory $ 80,650 $ 69,477

Property and Equipment_Net (Tab

Property and Equipment—Net (Tables)	9 Months Ended
	Sep. 30, 2015
Property, Plant and Equipment [Abstract]
Property and Equipment - Net	Property and equipment—net consisted of the following as of September 30, 2015 and December 31, 2014 (in thousands): September 30, December 31, Land $ 21,685 $ 13,895 Building and building improvements 22,283 20,166 Evaluation units 40,984 31,474 Computer equipment and software 43,658 31,821 Furniture and fixtures 7,054 5,096 Construction-in-progress 10,248 3,902 Leasehold improvements 9,070 7,998 Total property and equipment 154,982 114,352 Less: accumulated depreciation (71,610 ) (55,433 ) Property and equipment—net $ 83,372 $ 58,919

Business Combinations (Tables)

Business Combinations (Tables)	9 Months Ended
	Sep. 30, 2015
Business Combinations [Abstract]
Schedule of Purchase Price	The total purchase price was as follows (in thousands): Purchase Price: Cash $ 40,914 Estimated fair value of shares withheld for taxes 379 Estimated fair value of earned equity awards assumed by Fortinet 471 Total purchase price $ 41,764
Schedule of Allocation of Purchase Price	Total allocation of the purchase price was as follows (in thousands): Cash and cash equivalents $ 3,268 Accounts receivable 8,316 Inventory 11,854 Prepaid expenses and other assets 2,409 Property and equipment 983 Deferred tax assets 18,585 Identifiable intangible assets 19,600 Goodwill 1,436 Total assets acquired 66,451 Deferred revenue 9,800 Accounts payable and accrued liabilities 14,887 Total liabilities assumed 24,687 Total purchase price allocation $ 41,764
Schedule of Acquired Intangible Assets	The estimated useful life and fair values of the acquired identifiable intangible assets were as follows (in thousands, except for estimated useful life): Estimated Useful Life (in years) Fair Values Customer relationships 5 $ 12,200 Developed technologies 4 7,200 Trade name 0.5 200 Total $ 19,600
Pro Forma Information	The following pro forma financial information for all periods presented includes purchase accounting adjustments for amortization charges from acquired intangible assets, depreciation of acquired property, plant and equipment, stock-based compensation and related tax effects (in thousands): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Pro forma revenue $ 261,199 $ 218,363 $ 750,442 $ 615,581 Pro forma income (loss) from operations $ (5,968 ) $ 11,194 $ (15,368 ) $ 20,768 Pro forma net income (loss) $ 4,959 $ 572 $ (2,619 ) $ 4,173 Pro forma net income (loss) per basic $ 0.03 $ — $ (0.02 ) $ 0.03 Pro forma net income (loss) per diluted $ 0.03 $ — $ (0.01 ) $ 0.02

Goodwill and Other Intangible30

Goodwill and Other Intangible Assets - Net (Tables)	9 Months Ended
	Sep. 30, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The following table presents the changes in the carrying amount of goodwill (in thousands): Amount Balance—December 31, 2014 $ 2,824 Addition due to business acquisition 1,436 Balance—September 30, 2015 $ 4,260
Schedule of Other Intangible Assets - Net	The following tables present other intangible assets—net (in thousands): September 30, 2015 Weighted Average Useful Life (in years) Gross Accumulated Amortization Net Other intangible assets—net: Customer relationships 5.0 $ 12,200 $ 610 $ 11,590 Developed technologies 3.6 11,184 3,907 7,277 Trade names 0.5 200 100 100 Total other intangible assets—net $ 23,584 $ 4,617 $ 18,967 December 31, 2014 Weighted Average Useful Life (in years) Gross Accumulated Amortization Net Other intangible assets—net: Developed technologies 3.6 $ 5,606 $ 3,128 $ 2,478 Customer relationships 6.0 500 146 354 Total other intangible assets—net $ 6,106 $ 3,274 $ 2,832
Schedule of Estimated Future Amortization Expense	The following table summarizes estimated future amortization expense of other intangible assets—net (in thousands): Amount 2015 (remainder) $ 1,327 2016 4,600 2017 4,240 2018 4,240 2019 3,340 Thereafter 1,220 Total $ 18,967

Net Income Per Share (Tables)

Net Income Per Share (Tables)	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	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 Nine Months Ended September 30, September 30, September 30, September 30, Numerator: Net income $ 8,169 $ 4,056 $ 10,521 $ 18,530 Denominator: Basic shares: Weighted-average common stock outstanding—basic 171,648 164,294 169,898 163,289 Diluted shares: Weighted-average common stock outstanding—basic 171,648 164,294 169,898 163,289 Effect of potentially dilutive securities: Stock options 3,451 4,405 3,669 4,728 RSUs (including PSUs) 2,742 993 2,335 692 ESPP 56 35 61 26 Weighted-average shares used to compute diluted net income per share 177,897 169,727 175,963 168,735 Net income per share: Basic $ 0.05 $ 0.02 $ 0.06 $ 0.11 Diluted $ 0.05 $ 0.02 $ 0.06 $ 0.11
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	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 Nine Months Ended September 30, September 30, September 30, September 30, Stock options 265 3,023 271 4,101 RSUs (including PSUs) 1,331 696 1,026 879 ESPP 209 226 126 133 1,805 3,945 1,423 5,113

Deferred Revenue (Tables)

Deferred Revenue (Tables)	9 Months Ended
	Sep. 30, 2015
Deferred Revenue Disclosure [Abstract]
Deferred Revenue, by Arrangement, Disclosure	Deferred revenue consisted of the following as of September 30, 2015 and December 31, 2014 (in thousands): September 30, December 31, Product $ 6,134 $ 4,642 Service 700,777 554,115 Total deferred revenue $ 706,911 $ 558,757 Reported as: Current $ 471,118 $ 368,929 Non-current 235,793 189,828 Total deferred revenue $ 706,911 $ 558,757

Restructuring Charges (Tables)

Restructuring Charges (Tables)	9 Months Ended
	Sep. 30, 2015
Restructuring and Related Activities [Abstract]
Summary of Restructuring Activity	The following table provides a summary of restructuring activity as of September 30, 2015 (in thousands): Employee Severance and Other Benefits Contract Terminations and Other Charges Total Balance as of December 31, 2014 $ — $ — $ — Costs incurred 5,469 414 5,883 Less cash payments (1,858 ) (62 ) (1,920 ) Less non-cash charges (219 ) (191 ) (410 ) Balance as of September 30, 2015 $ 3,392 $ 161 $ 3,553

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Contractual Obligation, Fiscal Year Maturity Schedule	The following table summarizes our future principal contractual obligations as of September 30, 2015 (in thousands): Total 2015 (remainder) 2016 2017 2018 2019 Thereafter Operating lease commitments $ 56,775 $ 4,167 $ 15,679 $ 10,879 $ 8,404 $ 7,053 $ 10,593 Inventory purchase commitments 75,984 73,038 2,946 — — — — Other contractual commitments and open purchase orders 38,072 26,233 7,995 2,149 751 609 335 Total $ 170,831 $ 103,438 $ 26,620 $ 13,028 $ 9,155 $ 7,662 $ 10,928
Schedule of Product Warranty Liability	Accrued warranty activities are summarized as follows (in thousands): Nine Months Ended September 30, September 30, Accrued warranty balance—beginning of the period $ 4,269 $ 3,037 Warranty costs incurred (3,413 ) (2,597 ) Provision for warranty for the period, including warranty liabilities assumed in connection with a business acquisition 3,638 3,786 Adjustment related to pre-existing warranties (94 ) (540 ) Accrued warranty balance—end of the period $ 4,400 $ 3,686

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The following table summarizes the weighted-average assumptions relating to our employee stock options: Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Expected term in years 4.3 4.9 4.3 4.9 Volatility 37 % 41 % 38 % 43 % Risk-free interest rate 1.6 % 1.6 % 1.5 % 1.7 % Dividend rate — % — % — % — %
Schedule of Share-based Compensation, Stock Options, Activity	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 656 41.02 Forfeited (123 ) 26.69 Exercised (4,016 ) 11.38 Balance—September 30, 2015 7,219 $ 19.16 Options vested and expected to vest—September 30, 2015 7,155 $ 18.97 2.8 $ 169,925 Options exercisable—September 30, 2015 6,021 $ 16.40 2.2 $ 157,064
Schedule of Share-based Payment Award, Stock Options, Additional Information	Additional information related to our stock options is summarized below (in thousands, except per share amounts): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Weighted-average fair value per share granted $ 15.89 $ 9.13 $ 13.60 $ 8.76 Intrinsic value of options exercised 40,132 17,728 103,170 49,490 Fair value of options vested 2,491 4,393 9,001 13,163
Schedule of Share-based Compensation, Restricted Stock Units Award Activity	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 and assumed through business acquisition 5,385 40.01 Forfeited (675 ) 27.80 Vested (1,776 ) 22.35 Balance—September 30, 2015 9,225 $ 32.66 RSUs expected to vest—September 30, 2015 7,899 $ 32.90
Schedule of Share-based Compensation, Shares Withheld for Taxes	The following summarizes the number and value of the shares withheld for employee taxes (in thousands): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Shares withheld for taxes 245 124 590 381 Amount withheld for taxes $ 11,628 $ 2,985 $ 22,989 $ 8,506
Schedule of Share-based Payment Award, Equity Instruments Other than Options, Valuation Assumptions	The following table summarizes the weighted-average assumptions relating to our PSUs granted to our executive officers: Nine Months Ended September 30, September 30, Expected term in years 3.0 3.0 Volatility 38 % 47 % Risk-free interest rate 1.1 % 0.9 % Dividend rate — % — %
Share-based Compensation, Performance Shares Award Activity	The following table summarizes the activity and related information for PSUs for the periods presented below (in thousands, except per share amounts): Nine Months Ended September 30, September 30, Shares granted to executive officers and employees 206 120 Weighted-average fair value per share granted $ 34.86 $ 21.21
Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions	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 Nine Months Ended September 30, September 30, September 30, September 30, Expected term in years 0.5 0.5 0.5 0.5 Volatility 32 % 32 % 31 % 34 % Risk-free interest rate 0.2 % 0.1 % 0.1 % 0.1 % Dividend rate — % — % — % — %
Schedule of Share-based Payment Award Employee Stock Purchase Plan Additional Information	Additional information related to the ESPP is provided below (in thousands, except per share amounts): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Weighted-average fair value per share granted $ 11.42 $ 6.03 $ 8.23 $ 5.91 Shares issued under the ESPP 337 346 764 770 Weighted-average price per share issued $ 28.05 $ 19.38 $ 24.30 $ 18.17
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs	Stock-based compensation expense is included in costs and expenses as follows (in thousands): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Cost of product revenue $ 291 $ 60 $ 641 $ 351 Cost of service revenue 1,849 1,522 5,141 4,214 Research and development 6,663 4,505 17,361 12,558 Sales and marketing 13,904 7,397 34,482 18,890 General and administrative 3,612 1,183 9,376 6,300 Total stock-based compensation expense $ 26,319 $ 14,667 $ 67,001 $ 42,313
Schedule of Employee Service Share based Compensation Allocation of Recognized Period Costs by Award Type	The following table summarizes stock-based compensation expense by award type (in thousands): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Stock options $ 2,669 $ 4,282 $ 9,141 $ 13,395 RSUs (including PSUs) 21,996 9,275 53,674 25,886 ESPP 1,654 1,110 4,186 3,032 Total stock-based compensation expense $ 26,319 $ 14,667 $ 67,001 $ 42,313
Income Tax Benefit from Stock Option Plans	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 Nine Months Ended September 30, September 30, September 30, September 30, Income tax benefit associated with stock-based compensation $ 5,224 $ 4,225 $ 12,867 $ 11,821

Segment and Significant Custo36

Segment and Significant Customer Information (Tables)	9 Months Ended
	Sep. 30, 2015
Segment Reporting [Abstract]
Revenue from External Customers by Geographic Areas	Revenue by geographic region is based on the billing address of the customer. The following table sets forth revenue (in thousands): Three Months Ended Nine Months Ended Revenue September 30, September 30, September 30, September 30, Americas: United States $ 72,767 $ 50,329 $ 202,491 $ 144,794 Canada 26,027 21,104 72,676 59,837 Other Americas 14,371 10,785 38,151 28,404 Total Americas 113,165 82,218 313,318 233,035 Europe, Middle East, and Africa (“EMEA”) 91,740 66,157 250,808 185,354 Asia Pacific (“APAC”) 55,163 44,973 148,613 128,006 Total revenue $ 260,068 $ 193,348 $ 712,739 $ 546,395
Long-lived Assets by Geographic Areas	The following table sets forth property and equipment by geographic region as of September 30, 2015 and December 31, 2014 (in thousands): Property and Equipment — net September 30, December 31, Americas: United States $ 58,372 $ 46,116 Canada 7,811 6,054 Other Americas 1,853 875 Total Americas 68,036 53,045 EMEA: France 9,369 2,052 Other EMEA 2,236 1,204 Total EMEA 11,605 3,256 APAC 3,731 2,618 Total property and equipment—net $ 83,372 $ 58,919
Schedule of revenue by major customers	The following customers, each of which is a distributor, accounted for 10% or more of our revenue: Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Exclusive Networks Group 17 % 15 % 17 % 14 % Fin Tec Computers * 11 % * * * Represents less than 10%
Schedule of receivables by major customers	The following customers, each of which is a distributor, accounted for 10% or more of net accounts receivable: September 30, December 31, Exclusive Networks Group 19 % 18 % Ingram Micro 11 % * Fin Tec Computer 10 % * * Represents less than 10%

Accumulated Other Comprehensi37

Accumulated Other Comprehensive Loss (Tables)	9 Months Ended
	Sep. 30, 2015
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule of Accumulated Other Comprehensive Loss	The following table summarizes the changes in accumulated balances of other comprehensive loss (in thousands): Unrealized Gains (Losses) on Investments Tax benefit (provision) related to items of other comprehensive income or loss Total Beginning balance as of December 31, 2014 $ (540 ) $ 191 $ (349 ) Other comprehensive income before reclassifications 407 (143 ) 264 Amounts reclassified from accumulated other comprehensive loss (7 ) 2 (5 ) Net current-period other comprehensive income 400 (141 ) 259 Ending balance as of September 30, 2015 $ (140 ) $ 50 $ (90 )
Reclassification out of Accumulated Other Comprehensive Loss	The following table provides details about the reclassification out of accumulated other comprehensive loss (in thousands): Nine Months Ended September 30, 2015 Details about Accumulated Other Comprehensive Loss Components Amount Reclassified from Accumulated Other Comprehensive Loss Affected Line Item in the Statement Where Net Income is Presented Unrealized gains on investments $ (7 ) Other expense—net Tax provision related to items of other comprehensive income 2 Provision for (benefit from)income taxes Total reclassification for the period $ (5 )

Foreign Currency Derivatives (T

Foreign Currency Derivatives (Tables)	9 Months Ended
	Sep. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Notional Amounts of Outstanding Derivative Positions	The notional amount of our forward exchange contract to hedge balance sheet accounts were (in thousands): Buy/Sell Notional Currency—As of September 30, 2015 CAD Sell $ 9,653 Currency—As of December 31, 2014 CAD Buy $ 6,879

Financial Instruments and Fai39

Financial Instruments and Fair Value Measurements , Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 629,092	$ 709,030
Unrealized Gains	347	384
Unrealized Losses	(487)	(924)
Fair Value	628,952	708,490
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	244,812	356,625
Less Than 12 Months, Unrealized Losses	(384)	(907)
12 Months or Greater, Fair Value	38,634	6,011
12 Months or Greater, Unrealized Losses	(103)	(17)
Total, Fair Value	283,446	362,636
Total, Unrealized Losses	(487)	(924)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Due within one year	367,446	436,766
Due within one to three years	261,506	271,724
Fair Value	628,952	708,490
Corporate debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	485,236	589,526
Unrealized Gains	265	365
Unrealized Losses	(470)	(875)
Fair Value	485,031	589,016
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	217,790	317,011
Less Than 12 Months, Unrealized Losses	(370)	(858)
12 Months or Greater, Fair Value	37,622	6,011
12 Months or Greater, Unrealized Losses	(100)	(17)
Total, Fair Value	255,412	323,022
Total, Unrealized Losses	(470)	(875)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	485,031	589,016
Commercial paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	59,936	51,156
Unrealized Gains	6	3
Unrealized Losses	(10)	(4)
Fair Value	59,932	51,155
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	16,720	8,185
Less Than 12 Months, Unrealized Losses	(10)	(4)
12 Months or Greater, Fair Value	0	0
12 Months or Greater, Unrealized Losses	0	0
Total, Fair Value	16,720	8,185
Total, Unrealized Losses	(10)	(4)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	59,932	51,155
Municipal bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	59,251	39,745
Unrealized Gains	71	15
Unrealized Losses	(7)	(39)
Fair Value	59,315	39,721
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	10,302	26,684
Less Than 12 Months, Unrealized Losses	(4)	(39)
12 Months or Greater, Fair Value	1,012	0
12 Months or Greater, Unrealized Losses	(3)	0
Total, Fair Value	11,314	26,684
Total, Unrealized Losses	(7)	(39)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	59,315	39,721
Certificates of deposit and term deposits [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,668	22,854
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	8,668	22,854
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	8,668	22,854
U.S. government and agency securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	16,001	5,749
Unrealized Gains	5	1
Unrealized Losses	0	(6)
Fair Value	16,006	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	$ 16,006	$ 5,744

Financial Instruments and Fai40

Financial Instruments and Fair Value Measurements , Fair Value Measurements (Details) - USD ($)	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers between Level 1 and Level 2 of the fair value hierarchy during the period	$ 0
Estimate of Fair Value [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	712,635,000	$ 721,801,000
Estimate of Fair Value [Member] | Recurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	83,685,000	15,309,000
Estimate of Fair Value [Member] | Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	628,950,000	706,492,000
Estimate of Fair Value [Member] | Corporate debt securities [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	485,031,000	589,016,000
Estimate of Fair Value [Member] | Corporate debt securities [Member] | Recurring [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] | Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	485,031,000	589,016,000
Estimate of Fair Value [Member] | Commercial paper [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	61,932,000	51,155,000
Estimate of Fair Value [Member] | Commercial paper [Member] | Recurring [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] | Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	61,932,000	51,155,000
Estimate of Fair Value [Member] | Municipal bonds [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	59,315,000	39,721,000
Estimate of Fair Value [Member] | Municipal bonds [Member] | Recurring [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] | Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	59,315,000	39,721,000
Estimate of Fair Value [Member] | Certificates of deposit and term deposits [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	8,668,000	22,854,000
Estimate of Fair Value [Member] | Certificates of deposit and term deposits [Member] | Recurring [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] | Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	8,668,000	22,854,000
Estimate of Fair Value [Member] | Money market funds [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	81,683,000	13,311,000
Estimate of Fair Value [Member] | Money market funds [Member] | Recurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	81,683,000	13,311,000
Estimate of Fair Value [Member] | Money market funds [Member] | Recurring [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] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	16,006,000	5,744,000
Estimate of Fair Value [Member] | U.S. government and agency securities [Member] | Recurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	2,002,000	1,998,000
Estimate of Fair Value [Member] | U.S. government and agency securities [Member] | Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	14,004,000	3,746,000
Reported as [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	712,635,000	721,801,000
Reported as [Member] | Recurring [Member] | Cash equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	83,683,000	13,311,000
Reported as [Member] | Recurring [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	367,446,000	436,766,000
Reported as [Member] | Recurring [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	$ 261,506,000	$ 271,724,000

Inventory (Details)

Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Inventory [Abstract]
Raw materials	$ 13,594	$ 10,617
Finished goods	67,056	58,860
Inventory	80,650	69,477
Finished goods held by distributors	1,500	1,200
Materials at contract manufacturers	$ 4,200	$ 4,800

Property and Equipment_Net (Det

Property and Equipment—Net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	$ 154,982		$ 154,982		$ 114,352
Less: accumulated depreciation	(71,610)		(71,610)		(55,433)
Property and equipment - net	83,372		83,372		58,919
Depreciation expense	7,500	$ 5,400	20,300	$ 15,300
Land [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	21,685		21,685		13,895
Building and building improvements [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	22,283		22,283		20,166
Evaluation units [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	40,984		40,984		31,474
Computer equipment and software [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	43,658		43,658		31,821
Furniture and fixtures [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	7,054		7,054		5,096
Construction-in-progress [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	10,248		10,248		3,902
Leasehold improvements [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	$ 9,070		$ 9,070		$ 7,998

Investments in Privately-Held43

Investments in Privately-Held Companies (Details) $ in Millions	9 Months Ended
	Sep. 30, 2015USD ($)privately_held_company
Investments, All Other Investments [Abstract]
Number of privately-held companies	3
Investments in equity securities of privately-held companies | $	$ 10.3

Business Combinations , Purchas

Business Combinations , Purchase Price (Details) - Meru Networks, Inc. [Member] $ in Thousands	Jul. 08, 2015USD ($)
Acquisition Purchase Price [Abstract]
Cash	$ 40,914
Estimated fair value of shares withheld for taxes	379
Estimated fair value of earned equity awards assumed by Fortinet	471
Total purchase price	$ 41,764

Business Combinations , Allocat

Business Combinations , Allocation of Purchase Price (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Jul. 08, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill	$ 4,260		$ 2,824
Meru Networks, Inc. [Member]
Business Acquisition [Line Items]
Cash and cash equivalents		$ 3,268
Accounts receivable		8,316
Inventory		11,854
Prepaid expenses and other assets		2,409
Property and equipment		983
Deferred tax assets		18,585
Identifiable intangible assets		19,600
Goodwill		1,436
Total assets acquired		66,451
Deferred revenue		9,800
Accounts payable and accrued liabilities		14,887
Total liabilities assumed		24,687
Total purchase price allocation		$ 41,764

Business Combinations , Intangi

Business Combinations , Intangible Assets Acquired (Details) - Meru Networks, Inc. [Member] $ in Thousands	Jul. 08, 2015USD ($)
Business Acquisition [Line Items]
Fair values	$ 19,600
Customer Relationships [Member]
Business Acquisition [Line Items]
Estimated Useful Life (in years)	5 years
Fair values	$ 12,200
Developed Technologies [Member]
Business Acquisition [Line Items]
Estimated Useful Life (in years)	4 years
Fair values	$ 7,200
Trade Name [Member]
Business Acquisition [Line Items]
Estimated Useful Life (in years)	6 months
Fair values	$ 200

Business Combinations , Pro For

Business Combinations , Pro Forma Information (Details) - Meru Networks, Inc. [Member] - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Business Acquisition [Line Items]
Revenue of acquiree since acquisition date	$ 12,000
Net loss of acquiree since acquisition date	$ 9,600
Pro forma revenue		$ 261,199	$ 218,363	$ 750,442	$ 615,581
Pro forma income (loss) from operations		(5,968)	11,194	(15,368)	20,768
Pro forma net income (loss)		$ 4,959	$ 572	$ (2,619)	$ 4,173
Pro forma net income (loss) per basic (USD per share)		$ 0.03	$ 0	$ (0.02)	$ 0.03
Pro forma net income (loss) per diluted (USD per share)		$ 0.03	$ 0	$ (0.01)	$ 0.02

Business Combinations , Additio

Business Combinations , Additional Information (Details) - USD ($) $ in Thousands	Jul. 08, 2015	Sep. 30, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill		$ 4,260	$ 2,824
Meru Networks, Inc. [Member]
Business Acquisition [Line Items]
Cash consideration	$ 40,914
Withholding tax liability	379
Purchase price	41,764
Goodwill	$ 1,436
Meru Networks, Inc. [Member] | Restricted Stock Units (RSUs) [Member]
Business Acquisition [Line Items]
Fortinet RSUs issued for conversion of Meru RSUs	53,401
Meru Networks, Inc. [Member] | General and administrative [Member]
Business Acquisition [Line Items]
Acquisition-related costs		$ 1,700

Goodwill and Other Intangible49

Goodwill and Other Intangible Assets - Net , Additional Information (Details) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill impairment	$ 0			$ 0
Impairment of intangible assets		$ 1,600,000
Amortization expense	$ 1,300,000		$ 200,000	$ 1,900,000	$ 1,200,000

Goodwill and Other Intangible50

Goodwill and Other Intangible Assets - Net , Changes in Carrying Amount of Goodwill (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2015USD ($)
Goodwill [Roll Forward]
Balance, beginning	$ 2,824
Addition due to business acquisition	1,436
Balance, ending	$ 4,260

Goodwill and Other Intangible51

Goodwill and Other Intangible Assets - Net , Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross	$ 23,584	$ 6,106
Accumulated Amortization	4,617	3,274
Net	$ 18,967	$ 2,832
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years	6 years
Gross	$ 12,200	$ 500
Accumulated Amortization	610	146
Net	$ 11,590	$ 354
Developed Technologies [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	3 years 7 months 21 days	3 years 7 months 6 days
Gross	$ 11,184	$ 5,606
Accumulated Amortization	3,907	3,128
Net	$ 7,277	$ 2,478
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	6 months
Gross	$ 200
Accumulated Amortization	100
Net	$ 100

Goodwill and Other Intangible52

Goodwill and Other Intangible Assets - Net , Future Amortization of Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
2015 (remainder)	$ 1,327
2,016	4,600
2,017	4,240
2,018	4,240
2,019	3,340
Thereafter	1,220
Net	$ 18,967	$ 2,832

Net Income Per Share , Calculat

Net Income Per Share , Calculation of Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share [Line Items]
Net income	$ 8,169	$ 4,056	$ 10,521	$ 18,530
Basic shares:
Weighted-average common shares outstanding-basic (in shares)	171,648	164,294	169,898	163,289
Diluted shares:
Weighted-average common shares outstanding-basic (in shares)	171,648	164,294	169,898	163,289
Effect of potentially dilutive securities:
Weighted-average shares used to compute diluted net income per share (in shares)	177,897	169,727	175,963	168,735
Net income per share:
Basic (in dollars per share)	$ 0.05	$ 0.02	$ 0.06	$ 0.11
Diluted (in dollars per share)	$ 0.05	$ 0.02	$ 0.06	$ 0.11
Stock options [Member]
Effect of potentially dilutive securities:
Employee stock options and purchase rights (in shares)	3,451	4,405	3,669	4,728
RSUs (including PSUs) [Member]
Effect of potentially dilutive securities:
Employee stock options and purchase rights (in shares)	2,742	993	2,335	692
ESPP [Member]
Effect of potentially dilutive securities:
Employee stock options and purchase rights (in shares)	56	35	61	26

Net Income Per Share , Anti Dil

Net Income Per Share , Anti Dilutive Securities (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	1,805	3,945	1,423	5,113
Stock options [Member] | Stock Compensation Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	265	3,023	271	4,101
RSUs (including PSUs) [Member] | Stock Compensation Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	1,331	696	1,026	879
ESPP [Member] | Stock Compensation Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	209	226	126	133

Deferred Revenue (Details)

Deferred Revenue (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Deferred Revenue Arrangement [Line Items]
Short-term	$ 471,118	$ 368,929
Long-term	235,793	189,828
Total deferred revenue	706,911	558,757
Product [Member]
Deferred Revenue Arrangement [Line Items]
Total deferred revenue	6,134	4,642
Service [Member]
Deferred Revenue Arrangement [Line Items]
Total deferred revenue	$ 700,777	$ 554,115

Restructuring Charges , Restruc

Restructuring Charges , Restructuring Activity (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Restructuring Reserve [Roll Forward]
Balance, beginning			$ 0
Costs incurred	$ 5,883	$ 0	5,883	$ 0
Less cash payments			(1,920)
Less non-cash charges			(410)
Balance, ending	3,553		3,553
Employee Severance and Other Benefits [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning			0
Costs incurred			5,469
Less cash payments			(1,858)
Less non-cash charges			(219)
Balance, ending	3,392		3,392
Contract Terminations and Other Charges [Member]
Restructuring Reserve [Roll Forward]
Balance, beginning			0
Costs incurred			414
Less cash payments			(62)
Less non-cash charges			(191)
Balance, ending	$ 161		$ 161

Restructuring Charges , Additio

Restructuring Charges , Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Restructuring Cost and Reserve [Line Items]
Restructuring charges expected	$ 6,300		$ 6,300
Restructuring charges	5,883	$ 0	5,883	$ 0
Restructuring reserve	3,553		3,553		$ 0
Accrued Liabilities [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	2,700		2,700
Other Liabilities [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	$ 900		$ 900

Commitments and Contingencies58

Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Commitments and Contingencies Disclosure [Abstract]
Rent expense	$ 3,700	$ 2,600	$ 9,700	$ 7,700
Open purchase orders	75,984		75,984
Other contract commitments and open purchase orders	$ 38,072		$ 38,072

Commitments and Contingencies O

Commitments and Contingencies Other Contractual Commitments and Open Purchase Orders (Details) $ in Thousands	Sep. 30, 2015USD ($)
Operating lease commitments:
Operating leases commitments, 2015 (remainder)	$ 4,167
Operating lease commitments, 2016	15,679
Operating lease commitments, 2017	10,879
Operating lease commitments, 2018	8,404
Operating lease commitments, 2019	7,053
Operating lease commitments, Thereafter	10,593
Operating lease commitments	56,775
Inventory purchase commitments:
Inventory purchase commitments, 2015 (remainder)	73,038
Inventory purchase commitments, 2016	2,946
Inventory purchase commitments, 2017	0
Inventory purchase commitments, 2018	0
Inventory purchase commitments, 2019	0
Inventory purchase commitments, Thereafter	0
Inventory purchase commitments	75,984
Other contractual commitments and open purchase orders:
Other contractual commitments and open purchase orders, 2015 (remainder)	26,233
Other contractual commitments and open purchase orders, 2016	7,995
Other contractual commitments and open purchase orders, 2017	2,149
Other contractual commitments and open purchase orders, 2018	751
Other contractual commitments and open purchase orders, 2019	609
Other contractual commitments and open purchase orders, Thereafter	335
Other contractual commitments and open purchase orders	38,072
Contractual Obligation	170,831
Contractual Obligation, 2015 (remainder)	103,438
Contractual Obligation, 2016	26,620
Contractual Obligation, 2017	13,028
Contractual Obligation, 2018	9,155
Contractual Obligation, 2019	7,662
Contractual Obligation, Thereafter	$ 10,928

Commitments and Contingencies W

Commitments and Contingencies Warranties (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Movement in Standard Product Warranty Accrual [Roll Forward]
Accrued warranty balance—beginning of the period	$ 4,269	$ 3,037
Warranty costs incurred	(3,413)	(2,597)
Provision for warranty for the period, including warranty liabilities assumed in connection with a business acquisition	3,638	3,786
Adjustment related to pre-existing warranties	(94)	(540)
Accrued warranty balance—end of the period	$ 4,400	$ 3,686

Stockholders' Equity , Addition

Stockholders' Equity , Additional Information (Details) - USD ($) $ in Thousands	Jul. 08, 2015	Sep. 30, 2015	Dec. 31, 2014
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding		9,225,000	6,291,000
Share-based Compensation Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (shares)		41,362,003
Meru Networks, Inc. [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of earned equity awards assumed by Fortinet	$ 471
Meru Networks, Inc. [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value of RSUs assumed and exchanged	$ 2,000
Shares outstanding		42,332

Stockholders' Equity , Employee

Stockholders' Equity , Employee Stock Options (Details) - Stock options [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
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	4 years 3 months 26 days	4 years 10 months 17 days
Volatility	37.00%	41.00%	38.00%	43.00%
Risk-free interest rate	1.60%	1.60%	1.50%	1.70%
Dividend rate	0.00%	0.00%	0.00%	0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Balance - Beginning (in shares)			10,702
Granted (in shares)			656
Forfeited (in shares)			(123)
Exercised (in shares)			(4,016)
Balance - Ending (in shares)	7,219		7,219
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)			41.02
Forfeited (in dollars per share)			26.69
Exercised (in dollars per share)			11.38
Balance - Ending (in dollars per share)	$ 19.16		$ 19.16
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options vested and expected to vest, Outstanding (in shares)	7,155		7,155
Options vested and expected to vest, Weighted average exercise price (in dollars per share)	$ 18.97		$ 18.97
Options vested and expected to vest, Weighted average remaining contractual life (in years)			2 years 9 months 1 day
Options vested and expected to vest, Aggregate intrinsic value	$ 169,925		$ 169,925
Options exercisable, Outstanding (in shares)	6,021		6,021
Options exercisable, Weighted average exercise price (in dollars per share)	$ 16.40		$ 16.40
Options exercisable, Weighted average remaining contractual life (in years)			2 years 2 months 19 days
Options exercisable, Aggregate intrinsic value	$ 157,064		$ 157,064
Compensation cost not yet recognized	$ 14,000		$ 14,000
Compensation cost not yet recognized period of recognition			2 years 7 months 23 days
Weighted-average fair value per share granted	$ 15.89	$ 9.13	$ 13.60	$ 8.76
Intrinsic value of options exercised	$ 40,132	$ 17,728	$ 103,170	$ 49,490
Total fair value of awards vested	$ 2,491	$ 4,393	$ 9,001	$ 13,163

Stockholders' Equity , Restrict

Stockholders' Equity , Restricted Stock Units Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 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			$ 22,989	$ 8,506
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			5,385
Forfeited			(675)
Vested			(1,776)
Balance, ending	9,225		9,225
RSUs expected to vest—September 30, 2015	7,899		7,899
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)			40.01
Forfeited, weighted-average grant-date fair value per share (in dollars per share)			27.80
Vested, weighted-average grant-date fair value per share (in dollars per share)			22.35
Balance, weighted-average grant-date fair value per share (in dollars per share)—ending	$ 32.66		32.66
RSUs expected to vest, weighted-average grant-date fair value per share (in dollars per share)—December 31, 2012	$ 32.90		$ 32.90
Compensation cost not yet recognized	$ 291,400		$ 291,400
Compensation cost not yet recognized period of recognition			3 years 1 month 17 days
Shares withheld for taxes	245	124	590	381
Tax withholding upon vesting of restricted stock awards	$ 11,628	$ 2,985	$ 22,989	$ 8,506

Stockholders' Equity , Performa

Stockholders' Equity , Performance Stock Units (Details) - Performance Shares [Member] - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Sep. 30, 2014
Performance Share, Weighted Average Assumptions [Abstract]
Expected term in years		3 years	2 years 11 months 19 days
Volatility		38.00%	47.00%
Risk-free interest rate		1.10%	0.90%
Dividend rate		0.00%	0.00%
Granted	0	206,000	120,000
Granted, weighted-average grant-date fair value per share (in dollars per share)		$ 34.86	$ 21.21
Compensation cost not yet recognized	$ 6.4	$ 6.4
Compensation cost not yet recognized period of recognition		2 years 1 month 13 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%

Stockholders' Equity , ESPP Inf

Stockholders' Equity , ESPP Information (Details) - Employee Stock Purchase Plan [Member] - $ / shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term in years	5 months 27 days	6 months	5 months 27 days	6 months
Volatility	32.00%	32.00%	31.00%	34.00%
Risk-free interest rate	0.20%	0.10%	0.10%	0.10%
Dividend rate	0.00%	0.00%	0.00%	0.00%
Weighted-average fair value per share granted (in dollars per share)	$ 11.42	$ 6.03	$ 8.23	$ 5.91
Shares issued under the ESPP (in shares)	337	346	764	770
Weighted-average price per share issued (in dollars per share)	$ 28.05	$ 19.38	$ 24.30	$ 18.17

Stockholders' Equity , Allocati

Stockholders' Equity , Allocation of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 26,319	$ 14,667	$ 67,001	$ 42,313
Income tax benefit from employee stock option plans	5,224	4,225	12,867	11,821
Cost of product revenue [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	291	60	641	351
Cost of services revenue [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	1,849	1,522	5,141	4,214
Research and development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	6,663	4,505	17,361	12,558
Sales and marketing [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	13,904	7,397	34,482	18,890
General and administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	3,612	1,183	9,376	6,300
Stock options [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	2,669	4,282	9,141	13,395
RSUs (including PSUs) [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	21,996	9,275	53,674	25,886
ESPP [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 1,654	$ 1,110	$ 4,186	$ 3,032

Stockholders' Equity , Share Re

Stockholders' Equity , Share Repurchase Program (Details) - Share Repurchase Program [Member] - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program, authorized amount			$ 200
Stock repurchased in the period, shares	0	0
Remaining authorized repurchase amount under the program	$ 122.5	$ 122.5

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income tax (benefit) expense	$ (9,329)	$ 11,729	$ (6,552)	$ 22,901
Pretax net (loss) income	$ (1,160)	$ 15,785	$ 3,969	$ 41,431
Effective income tax rate (percent)	804.00%	74.00%	(165.00%)	55.00%
Unrecognized tax benefits	$ 55,800		$ 55,800		$ 44,200
Unrecognized tax benefits that would favoraby affect effective tax rate	54,600		54,600
Accrued interest and penalties related to uncertain tax benefits	$ 5,000		$ 5,000

Defined Contribution Plans (Det

Defined Contribution Plans (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 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	$ 0.9	$ 0.7	$ 2.7	$ 1.9

Segment and Significant Custo70

Segment and Significant Customer Information (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015USD ($)	Sep. 30, 2014USD ($)	Sep. 30, 2015USD ($)Segment_Managersreportable_segmentbusiness_activityoperating_segment	Sep. 30, 2014USD ($)	Dec. 31, 2014USD ($)
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	$ 260,068	$ 193,348	$ 712,739	$ 546,395
Property and equipment - net	83,372		83,372		$ 58,919
Americas [Member]
Segment Reporting Information [Line Items]
Revenue	113,165	82,218	313,318	233,035
Property and equipment - net	68,036		68,036		53,045
United States
Segment Reporting Information [Line Items]
Revenue	72,767	50,329	202,491	144,794
Property and equipment - net	58,372		58,372		46,116
Canada [Member]
Segment Reporting Information [Line Items]
Revenue	26,027	21,104	72,676	59,837
Property and equipment - net	7,811		7,811		6,054
Other Americas [Member]
Segment Reporting Information [Line Items]
Revenue	14,371	10,785	38,151	28,404
Property and equipment - net	1,853		1,853		875
EMEA [Member]
Segment Reporting Information [Line Items]
Revenue	91,740	66,157	250,808	185,354
Property and equipment - net	11,605		11,605		3,256
FRANCE
Segment Reporting Information [Line Items]
Property and equipment - net	9,369		9,369		2,052
Europe (except France), Middle East and Africa [Member]
Segment Reporting Information [Line Items]
Property and equipment - net	2,236		2,236		1,204
APAC [Member]
Segment Reporting Information [Line Items]
Revenue	55,163	$ 44,973	148,613	$ 128,006
Property and equipment - net	$ 3,731		$ 3,731		$ 2,618

Segment and Significant Custo71

Segment and Significant Customer Information Significant Customers (Details) - Customer Concentration Risk [Member]	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Sales Revenue [Member] | Exclusive Networks Group [Member]
Concentration Risk [Line Items]
Percentage from a single customer	17.00%	15.00%	17.00%	14.00%
Sales Revenue [Member] | Fin Tec Computer [Member]
Concentration Risk [Line Items]
Percentage from a single customer		11.00%
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			10.00%
Accounts Receivable [Member] | Ingram Micro [Member]
Concentration Risk [Line Items]
Percentage from a single customer			11.00%

Accumulated Other Comprehensi72

Accumulated Other Comprehensive Loss (Changes in Accumulated Balances of Other Comprehensive Loss) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2015USD ($)
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ (349)
Other comprehensive income before reclassifications	264
Amounts reclassified from accumulated other comprehensive loss	(5)
Net current-period other comprehensive income	259
Ending balance	(90)
Tax Benefit (Provision) Related to Items of Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	191
Other comprehensive income before reclassifications	(143)
Amounts reclassified from accumulated other comprehensive loss	2
Net current-period other comprehensive income	(141)
Ending balance	50
Unrealized Gains (Losses) on Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(540)
Other comprehensive income before reclassifications	407
Amounts reclassified from accumulated other comprehensive loss	(7)
Net current-period other comprehensive income	400
Ending balance	$ (140)

Accumulated Other Comprehensi73

Accumulated Other Comprehensive Loss (Reclassification Out of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
OTHER EXPENSE—net	$ (653)	$ (1,005)	$ (2,160)	$ (1,968)
Provision for income taxes	9,329	(11,729)	6,552	(22,901)
Net income	$ 8,169	$ 4,056	10,521	$ 18,530
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Provision for income taxes			2
Net income			(5)
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			$ (7)

Foreign Currency Derivatives (D

Foreign Currency Derivatives (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Sell [Member]
Derivative [Line Items]
Notional amount of forward exchange contracts	$ 9,653
Buy [Member]
Derivative [Line Items]
Notional amount of forward exchange contracts		$ 6,879

Related Party Transactions (Det

Related Party Transactions (Details) - Law Firm where Board Member's Son is a Partner [Member] - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Related Party Transaction [Line Items]
Expenses for legal services	$ 0.9	$ 0.9	$ 3.7	$ 1.7
Amounts due and payable to the law firm	$ 1.4		$ 1.4		$ 1.3