Fortinet (FTNT) 10-Q 6 May 16 2016 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2016	Apr. 29, 2016
Document Information [Line Items]
Entity Registrant Name	FORTINET INC
Entity Central Index Key	1,262,039
Document Type	10-Q
Document Period End Date	Mar. 31, 2016
Amendment Flag	false
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		171,671,224

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
CURRENT ASSETS:
Cash and cash equivalents	$ 568,008	$ 543,277
Short-term investments	384,591	348,074
Accounts receivable—net of reserves for sales returns and doubtful accounts of $6,545 and $6,228 at March 31, 2016 and December 31, 2015, respectively	220,135	259,563
Inventory	78,239	83,868
Prepaid expenses and other current assets	34,728	35,761
Total current assets	1,285,701	1,270,543
LONG-TERM INVESTMENTS	241,888	272,959
DEFERRED TAX ASSETS	131,696	119,216
PROPERTY AND EQUIPMENT—net	115,782	91,067
OTHER INTANGIBLE ASSETS—net	16,457	17,640
GOODWILL	4,692	4,692
OTHER ASSETS	15,305	14,393
TOTAL ASSETS	1,811,521	1,790,510
CURRENT LIABILITIES:
Accounts payable	47,955	61,500
Accrued liabilities	33,543	33,028
Accrued payroll and compensation	58,165	61,111
Income taxes payable	9,230	8,379
Deferred revenue	538,449	514,652
Total current liabilities	687,342	678,670
DEFERRED REVENUE	298,739	276,651
INCOME TAX LIABILITIES	65,163	60,624
OTHER LIABILITIES	17,874	19,188
Total liabilities	$ 1,069,118	$ 1,035,133
COMMITMENTS AND CONTINGENCIES (Note 10)
STOCKHOLDERS’ EQUITY:
Common stock, $0.001 par value—300,000 shares authorized; 171,588 and 171,399 shares issued and outstanding at March 31, 2016 and December 31, 2015, respectively	$ 171	$ 171
Additional paid-in capital	718,849	687,658
Accumulated other comprehensive income (loss)	294	(933)
Retained earnings	23,089	68,481
Total stockholders’ equity	742,403	755,377
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 1,811,521	$ 1,790,510

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Unaudited) Parenthetical - USD ($) shares in Thousands, $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Reserves for sales returns and doubtful accounts	$ 6,545	$ 6,228
Common Stock, par value (dollars per share)	$ 0.001	$ 0.001
Common Stock, shares authorized	300,000	300,000
Common Stock, shares issued	171,588	171,399
Common Stock, shares outstanding	171,588	171,399

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
REVENUE:
Product	$ 124,572	$ 97,509
Service	160,004	115,377
Total revenue	284,576	212,886
COST OF REVENUE:
Product	49,359	41,368
Service	28,390	22,234
Total cost of revenue	77,749	63,602
GROSS PROFIT:
Product	75,213	56,141
Service	131,614	93,143
Total gross profit	206,827	149,284
OPERATING EXPENSES:
Research and development	44,966	35,816
Sales and marketing	147,403	100,609
General and administrative	19,802	11,961
Restructuring charges	328	0
Total operating expenses	212,499	148,386
OPERATING INCOME (LOSS)	(5,672)	898
INTEREST INCOME	1,746	1,422
OTHER EXPENSE—net	(1,312)	(677)
INCOME (LOSS) BEFORE INCOME TAXES	(5,238)	1,643
PROVISION FOR (BENEFIT FROM) INCOME TAXES	(1,809)	83
NET INCOME (LOSS)	$ (3,429)	$ 1,560
Net income (loss) per share (Note 8):
Basic (in dollars per share)	$ (0.02)	$ 0.01
Diluted (in dollars per share)	$ (0.02)	$ 0.01
Weighted-average shares outstanding:
Basic (in shares)	171,745	168,077
Diluted (in shares)	171,745	173,720

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Net income (loss)	$ (3,429)	$ 1,560
Other comprehensive income:
Unrealized gains on investments	1,888	885
Tax provision related to other items of other comprehensive income	(661)	(310)
Other comprehensive income—net of taxes	1,227	575
Comprehensive income (loss)	$ (2,202)	$ 2,135

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ (3,429)	$ 1,560
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	10,550	6,353
Amortization of investment premiums	1,497	1,938
Stock-based compensation	30,881	18,880
Other non-cash items—net	(372)	159
Changes in operating assets and liabilities:
Accounts receivable—net	38,920	23,621
Inventory	(527)	(6,296)
Deferred tax assets	(13,141)	(7,918)
Prepaid expenses and other current assets	1,029	(1,203)
Other assets	(911)	507
Accounts payable	(11,426)	(11,305)
Accrued liabilities	300	(3,450)
Accrued payroll and compensation	(2,945)	(3,149)
Other liabilities	(1,332)	(1,569)
Deferred revenue	46,106	40,696
Income taxes payable	5,391	5,795
Net cash provided by operating activities	100,591	64,619
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of investments	(115,672)	(120,991)
Sales of investments	2,867	6,679
Maturities of investments	108,557	135,363
Purchases of property and equipment	(29,956)	(4,927)
Net cash provided by (used in) investing activities	(34,204)	16,124
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock	17,785	28,955
Taxes paid related to net share settlement of equity awards	(9,441)	(6,600)
Repurchase and retirement of common stock	(50,000)	0
Net cash provided by (used in) financing activities	(41,656)	22,355
NET INCREASE IN CASH AND CASH EQUIVALENTS	24,731	103,098
CASH AND CASH EQUIVALENTS—Beginning of year	543,277	283,254
CASH AND CASH EQUIVALENTS—End of year	568,008	386,352
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Cash paid for income taxes—net	5,574	6,498
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Transfers of evaluation units from inventory to property and equipment	6,671	3,869
Liability for purchase of property and equipment and asset retirement obligations	$ 7,843	$ 2,140

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2016
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, 2015, contained in our Annual Report on Form 10-K (the “Form 10-K”) filed with the SEC on February 26, 2016. In the opinion of management, all adjustments, which includes normal recurring adjustments, considered necessary for a fair presentation have been included. All intercompany balances, transactions and cash flows have been eliminated. The results of operations for the three months ended March 31, 2016 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, 2015 is derived from the audited consolidated financial statements for the year ended December 31, 2015. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Actual results could differ materially from those estimates. There have been no material changes to our significant accounting policies as of and for the three months ended March 31, 2016. Recently Adopted Accounting Standards In September 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2015-16—Business Combinations—Simplifying the Accounting for Measurement-Period Adjustments, which 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. We adopted ASU 2015-16 on January 1, 2016. The adoption of ASU 2015-16 did not have any impact on our consolidated financial statements. In April 2015, the FASB issued ASU 2015-05—Intangibles—Goodwill and Other—Internal—Use Software— Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement, which provides guidance on determining whether a cloud computing arrangement contains a software license. If a cloud computing arrangement includes a software license, then the customer should account for the software license element of the arrangement consistent with the acquisition of other software licenses. If a cloud computing arrangement does not include a software license, the customer should account for the arrangement as a service contract. We adopted ASU 2015-05 on a prospective basis beginning on January 1, 2016. The impact of ASU 2015-05 did not have a significant impact on our consolidated financial statements. In February 2015, the FASB issued ASU 2015-02—Consolidation—Amendments to the Consolidation Analysis, which updates the accounting guidance on consolidation requirements. This update changes the guidance with respect to the analysis that a reporting entity must perform to determine whether it should consolidate certain types of legal entities. ASU 2015-02 also makes several modifications to the consolidation guidance for variable interest entities (“VIEs”). We adopted ASU 2015-02 on January 1, 2016. The adoption of ASU 2015-02 did not have any impact on our consolidated financial statements. Recent Accounting Standards Not Yet Effective In March 2016, the FASB issued ASU 2016-09—Compensation—Stock Compensation—Improvements to Employee Share-Based Payment Accounting, which changes certain aspects of accounting for shared-based payments to employees. The new guidance will require all income tax effects of awards to be recognized in the income statement for the period in which the awards vest or are settled. It also allows an employer to repurchase more of an employee’s shares for tax withholding purposes without triggering liability accounting and to make a policy election to account for forfeitures as they occur. This new guidance will be effective for us beginning on January 1, 2017, and interim periods within those fiscal years. Early adoption is permitted in any annual or interim period for which financial statements have not been issued or made available for issuance, but all of the guidance must be adopted in the same period. We are currently evaluating the impact ASU 2016-09 will have on our consolidated financial statements. In February 2016, the FASB issued ASU 2016-02—Leases, which amends lease accounting requirements to begin recording assets and liabilities arising from leases on the balance sheet. The new guidance will also require significant additional disclosures about the amount, timing and uncertainty of cash flows from leases. This new guidance will be effective for us beginning on January 1, 2019 using a modified retrospective approach. The modified retrospective approach includes a number of optional practical expedients that entities may elect to apply. We are currently evaluating the impact ASU 2016-02 will have on our consolidated financial statements. In January 2016, the FASB issued ASU 2016-01—Financial Instruments—Overall—Recognition and Measurement of Financial Assets and Financial Liabilities, which modifies how entities measure equity investments and present changes in the fair value of financial liabilities. Under the new guidance, entities will have to measure equity investments that do not result in consolidation and are not accounted under the equity method at fair value and recognize any changes in fair value in net income unless the investments qualify for the new practicality exception. The practicality exception will apply to those equity investments that do not have a readily determinable fair value and do not qualify for the practical expedient to estimate fair value, and as such these investments may be measured at cost. ASU 2016-01 will be effective for us beginning on January 1, 2018. We do not expect the impact of ASU 2016-01 on our consolidated financial statements to be significant. In July 2015, the FASB issued ASU 2015-11—Inventory—Simplifying the Measurement of Inventory, which changes the measurement principle for inventory from the lower of cost or market to lower of cost and net realizable value. ASU 2015-11 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 or 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 ASU 2014-09—Revenue from Contracts with Customers, which creates 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. In March 2016, the FASB issued ASU 2016-08, which clarifies the implementation guidance on principal versus agent considerations. In April 2016, the FASB issued ASU 2016-10, which clarifies the implementation guidance on identifying performance obligations and licensing. These standards 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 these new standards on our consolidated financial statements.

Financial Instruments and Fair

Financial Instruments and Fair Value	3 Months Ended
	Mar. 31, 2016
Financial Instruments and Fair Value [Abstract]
FINANCIAL INSTRUMENTS AND FAIR VALUE	FINANCIAL INSTRUMENTS AND FAIR VALUE The following table summarizes our investments as of March 31, 2016 and December 31, 2015 (in thousands): March 31, 2016 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Corporate debt securities $ 410,265 $ 574 $ (250 ) $ 410,589 Commercial paper 75,465 7 (8 ) 75,464 Municipal bonds 54,198 53 (7 ) 54,244 Certificates of deposit and term deposits (1) 19,847 — — 19,847 U.S. government and agency securities 66,253 82 — 66,335 Total available-for-sale securities $ 626,028 $ 716 $ (265 ) $ 626,479 December 31, 2015 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Corporate debt securities $ 438,533 $ 30 $ (1,369 ) $ 437,194 Commercial paper 66,263 3 (34 ) 66,232 Municipal bonds 61,050 12 (40 ) 61,022 Certificates of deposit and term deposits (1) 14,897 — — 14,897 U.S. government and agency securities 41,727 3 (42 ) 41,688 Total available-for-sale securities $ 622,470 $ 48 $ (1,485 ) $ 621,033 (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 March 31, 2016 and December 31, 2015 (in thousands): March 31, 2016 Less Than 12 Months 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Corporate debt securities $ 141,018 $ (159 ) $ 50,269 $ (91 ) $ 191,287 $ (250 ) Commercial paper 16,754 (8 ) — — 16,754 (8 ) Municipal bonds 12,710 (6 ) 1,006 (1 ) 13,716 (7 ) Total available-for-sale securities $ 170,482 $ (173 ) $ 51,275 $ (92 ) $ 221,757 $ (265 ) December 31, 2015 Less Than 12 Months 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Corporate debt securities $ 348,534 $ (1,187 ) $ 42,033 $ (182 ) $ 390,567 $ (1,369 ) Commercial paper 31,977 (34 ) — — 31,977 (34 ) Municipal bonds 41,677 (36 ) 1,008 (4 ) 42,685 (40 ) U.S. government and agency securities 34,703 (42 ) — — 34,703 (42 ) Total available-for-sale securities $ 456,891 $ (1,299 ) $ 43,041 $ (186 ) $ 499,932 $ (1,485 ) The contractual maturities of our investments as of March 31, 2016 and December 31, 2015 were as follows (in thousands): March 31, December 31, Due within one year $ 384,591 $ 348,074 Due within one to three years 241,888 272,959 Total $ 626,479 $ 621,033 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 insignificant in the periods presented and are included in Other expense—net in our condensed consolidated statements of operations. We use the specific identification method to determine the cost basis of investments sold. 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 are attributable to changes in market conditions and not credit quality, and because we have concluded currently that we neither intend to sell nor is it more likely than not that we will be required to sell these investments prior to a recovery of par value, we do not consider these investments to be other-than temporarily impaired as of March 31, 2016 . 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 March 31, 2016 and December 31, 2015 (in thousands): March 31, 2016 December 31, 2015 Aggregate Fair Value Quoted Prices in Active Markets For Identical Assets Significant Other Observable Remaining Inputs Significant Other Unobservable Remaining Inputs Aggregate Fair Value Quoted Prices in Active Markets For Identical Assets Significant Other Observable Remaining Inputs Significant Other Unobservable Remaining Inputs (Level 1) (Level 2) (Level 3) (Level 1) (Level 2) (Level 3) Assets: Corporate debt securities $ 410,589 $ — $ 410,589 $ — $ 437,194 $ — $ 437,194 $ — Commercial paper 82,962 — 82,962 — 69,231 — 69,231 — Municipal bonds 54,244 — 54,244 — 61,022 — 61,022 — Certificates of deposit and term deposits 19,847 — 19,847 — 14,897 — 14,897 — Money market funds 48,599 48,599 — — 50,030 50,030 — — U.S. government and agency securities 66,335 50,326 16,009 — 41,688 25,693 15,995 — Total $ 682,576 $ 98,925 $ 583,651 $ — $ 674,062 $ 75,723 $ 598,339 $ — Reported as: Cash equivalents $ 56,097 $ 53,029 Short-term investments 384,591 348,074 Long-term investments 241,888 272,959 Total $ 682,576 $ 674,062 There were no transfers between Level 1 and Level 2 of the fair value hierarchy during the three months ended March 31, 2016 .

Inventory

Inventory	3 Months Ended
	Mar. 31, 2016
Inventory Disclosure [Abstract]
INVENTORY	INVENTORY Inventory consisted of the following as of March 31, 2016 and December 31, 2015 (in thousands): March 31, December 31, Raw materials $ 15,270 $ 15,425 Finished goods 62,969 68,443 Inventory $ 78,239 $ 83,868 Inventory includes finished goods held by distributors where revenue is recognized on a sell-through basis of $0.9 million and $1.1 million as of March 31, 2016 and December 31, 2015 , respectively. Inventory also includes materials at contract manufacturers of $4.9 million both as of March 31, 2016 and December 31, 2015 .

Property and Equipment_Net

Property and Equipment—Net	3 Months Ended
	Mar. 31, 2016
Property, Plant and Equipment [Abstract]
PROPERTY AND EQUIPMENT—Net	PROPERTY AND EQUIPMENT—net Property and equipment—net as of March 31, 2016 and December 31, 2015 consisted of the following (in thousands): March 31, December 31, Land $ 30,321 $ 21,683 Building and building improvements 39,454 28,841 Evaluation units 18,413 15,784 Computer equipment and software 49,701 45,632 Furniture and fixtures 10,536 8,901 Construction-in-progress 8,796 8,106 Leasehold improvements 13,182 11,179 Total property and equipment 170,403 140,126 Less: accumulated depreciation (54,621 ) (49,059 ) Property and equipment—net $ 115,782 $ 91,067 During the first quarter of 2016, we purchased certain real property in Union City, California, for cash of $18.5 million to support the growth in our business operations. Of the total cost, we allocated $8.7 million to land and $9.8 million to building. Depreciation expense was $9.4 million and $6.0 million during the three months ended March 31, 2016 and March 31, 2015, respectively.

Investments in Privately-Held C

Investments in Privately-Held Companies	3 Months Ended
	Mar. 31, 2016
Investments, All Other Investments [Abstract]
INVESTMENTS IN PRIVATELY-HELD COMPANIES	INVESTMENTS IN PRIVATELY-HELD COMPANIES Our investments in the equity securities of three privately-held companies totaled $10.3 million as of March 31, 2016 and December 31, 2015 . Each of these investments are accounted for as cost-basis investments, as we own less than 20% of the voting securities and do not have the ability to exercise significant influence over operating and financial policies of the respective entities. These investments are carried at historical cost and are recorded as Other assets on our condensed consolidated balance sheet and would be measured at fair value if indicators of impairment exist. As of March 31, 2016 , no events have occurred that would adversely affect the carrying value of these investments. We determined that we had a variable interest in these privately-held companies. However, we determined that we were not the primary beneficiary as we did not have the power to direct their activities that most significantly affect their economic performance. The variable interest entities were not required to be consolidated in our condensed consolidated financial statements.

Business Combinations

Business Combinations	3 Months Ended
	Mar. 31, 2016
Business Combinations [Abstract]
BUSINESS COMBINATIONS	BUSINESS COMBINATIONS On July 8, 2015, we completed our acquisition of all of the outstanding shares of Meru Networks, Inc. (“Meru”), a provider of Wi-Fi networking products and services. With this acquisition, we expect to 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. In 2015, 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. Total allocation of the purchase price was as follows (in thousands): Cash and cash equivalents $ 3,268 Accounts receivable 8,191 Inventory 11,610 Prepaid expenses and other assets 2,409 Property and equipment 920 Deferred tax assets 18,585 Identifiable intangible assets 19,600 Goodwill 1,868 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 $1.9 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 Customer relationships and trade name are amortized and the amortization expense is recorded in sales and marketing expenses in the condensed consolidated statement of operations. Developed technologies is amortized and the amortization expense is recorded in cost of product revenue in the condensed consolidated statement of operations.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets - Net	3 Months Ended
	Mar. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND OTHER INTANGIBLE ASSETS - Net	GOODWILL AND OTHER INTANGIBLE ASSETS—net Goodwill As of March 31, 2016 , we had goodwill of $4.7 million . There were no impairments to goodwill during the three months ended March 31, 2016 . Other Intangible Assets—net The following tables present other intangible assets—net as of March 31, 2016 and December 31, 2015 (in thousands): March 31, 2016 Weighted-Average Useful Life (in Years) Gross Accumulated Amortization Net Other intangible assets—net: Customer relationships 5.0 $ 12,200 $ 1,830 $ 10,370 Developed technologies and other 3.6 11,384 5,297 6,087 Total other intangible assets—net $ 23,584 $ 7,127 $ 16,457 December 31, 2015 Weighted-Average Useful Life (in Years) Gross Accumulated Amortization Net Other intangible assets—net: Customer relationships 5.0 $ 12,200 $ 1,220 $ 10,980 Developed technologies and other 3.6 11,384 4,724 6,660 Total other intangible assets—net $ 23,584 $ 5,944 $ 17,640 Amortization expense was $1.2 million and $0.3 million during the three months ended March 31, 2016 and March 31, 2015, respectively. The following table summarizes estimated future amortization expense of Other intangible assets—net (in thousands): Amount Years: 2016 (remainder) $ 3,417 2017 4,240 2018 4,240 2019 3,340 2020 1,220 Total $ 16,457

Net Income (Loss) Per Share

Net Income (Loss) Per Share	3 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
NET INCOME (LOSS) PER SHARE	NET INCOME (LOSS) PER SHARE Basic net income (loss) per share is computed by dividing net income (loss) by the weighted-average number of shares of common stock outstanding during the period. Diluted net income (loss) per share is computed by dividing net income (loss) 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 our 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 (loss) per share is as follows (in thousands, except per share amounts): Three Months Ended March 31, March 31, Numerator: Net income (loss) $ (3,429 ) $ 1,560 Denominator: Basic shares: Weighted-average common stock outstanding-basic 171,745 168,077 Diluted shares: Weighted-average common stock outstanding-basic 171,745 168,077 Effect of potentially dilutive securities: Stock options — 3,837 RSUs (including PSUs) — 1,741 ESPP — 65 Weighted-average shares used to compute diluted net income per share 171,745 173,720 Net income (loss) per share: Basic $ (0.02 ) $ 0.01 Diluted $ (0.02 ) $ 0.01 The following potentially dilutive shares of common stock were excluded from the computation of diluted net income (loss) per share for the periods presented, as their effect would have been antidilutive (in thousands): Three Months Ended March 31, March 31, Stock options 6,939 249 RSUs (including PSUs) 10,020 1,333 ESPP 282 169 17,241 1,751

Restructuring Charges

Restructuring Charges	3 Months Ended
	Mar. 31, 2016
Restructuring and Related Activities [Abstract]
RESTRUCTURING CHARGES	RESTRUCTURING CHARGES In connection with the acquisition of Meru, we initiated planned cost reduction and restructuring activities to improve our cost structure and operational efficiencies starting in the third quarter of 2015. We estimate that we will incur $8.0 million to $8.5 million of restructuring charges, consisting of severance and other benefits, contract terminations and other charges. We incurred $0.3 million of restructuring charges during the three months ended March 31, 2016 , which are included in operating expense in the condensed consolidated statements of operations. To date, we have incurred $7.9 million of charges related to this restructuring. These charges are primarily related to severance payments to be paid in cash. The following table provides a summary of restructuring activity as of March 31, 2016 (in thousands): Employee Severance and Other Benefits Contract Terminations and Other Charges Total Balance as of December 31, 2015 $ 3,689 $ 229 $ 3,918 Costs incurred 328 — 328 Less cash payments (1,282 ) (125 ) (1,407 ) Less non-cash charges (89 ) — (89 ) Balance as of March 31, 2016 $ 2,646 $ 104 $ 2,750 Cash payments for the restructuring activities are expected to be made through 2017, primarily relating to severance payments. The short-term portion of the restructuring reserve of $2.5 million is included in accrued liabilities and the remaining long-term portion of $0.2 million is included in other liabilities on the condensed consolidated balance sheet as of March 31, 2016 .

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES The following table summarizes our future principal contractual obligations as of March 31, 2016 (in thousands): Total 2016 (remainder) 2017 2018 2019 2020 Thereafter Operating lease commitments $ 60,677 $ 13,411 $ 12,897 $ 11,036 $ 8,734 $ 5,945 $ 8,654 Inventory purchase commitments 77,530 77,530 — — — — — Other contractual commitments and open purchase orders 49,048 41,207 3,461 1,590 930 930 930 Total $ 187,255 $ 132,148 $ 16,358 $ 12,626 $ 9,664 $ 6,875 $ 9,584 Operating Leases —We lease certain facilities under various non-cancelable operating leases, which expire through 2026. Certain leases require us to pay variable costs such as taxes, maintenance, and insurance. The terms of certain operating leases also provide for renewal options and escalation clauses. Rent expense was $4.6 million and $3.1 million during the three months ended March 31, 2016 and March 31, 2015, respectively. Rent expense is recognized using the straight-line method over the term of the lease. Inventory Purchase Commitments —Our independent contract manufacturers procure components and build our products based on our forecasts. These forecasts are based on estimates of future demand for our products, which are in turn based on historical trends and an analysis from our sales and marketing organizations, adjusted for overall market conditions. In order to reduce manufacturing lead times and plan for adequate component supply, we may issue purchase orders to some of our independent contract manufacturers which may not be cancelable. As of March 31, 2016 , we had $77.5 million of open purchase orders with our independent contract manufacturers that may not be cancelable. Other Contractual Commitments and Open Purchase Orders —In addition to commitments with contract manufacturers, we have open purchase orders and contractual obligations in the ordinary course of business for which we have not received goods or services. As of March 31, 2016 , we had $49.0 million in other contractual commitments that may not be cancelable. Warranties —Accrued warranty activities are summarized as follows (in thousands): Three Months Ended March 31, March 31, Accrued warranty balance—beginning of the period $ 3,144 $ 4,269 Warranty costs incurred (511 ) (1,095 ) Provision for warranty for the period 377 945 Adjustment related to pre-existing warranties (353 ) 222 Accrued warranty balance—end of the period $ 2,657 $ 4,341 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 fees, including contingent legal fees with related parties, costs and substantial settlement charges, and possibly subject us to damages and other penalties. 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 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	3 Months Ended
	Mar. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
STOCKHOLDERS' EQUITY	STOCKHOLDERS’ EQUITY Stock-Based Compensation Plans We have stock-based compensation plans pursuant to which we have granted stock options and RSUs, including PSUs. We also have an ESPP for all eligible employees. As of March 31, 2016 , there were a total of 45,616,141 shares of common stock available for grant under our stock-based compensation plans. Restricted Stock Units The following table summarizes the activity and related information for RSUs, including PSUs, 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, 2015 9,257 $ 32.97 Granted 2,831 23.87 Forfeited (441 ) 31.94 Vested (1,014 ) 28.45 Balance—March 31, 2016 10,633 $ 30.86 RSUs expected to vest—March 31, 2016 9,959 $ 30.71 As of March 31, 2016 , total compensation expense related to unvested RSUs, including PSUs, that were granted to employees and non-employees, but not yet recognized, was $303.8 million . This expense is expected to be amortized on a straight-line basis over a weighted-average vesting period of 3.0 years. We did not grant any PSUs during the three months ended March 31, 2016. The stock-based compensation expense related to PSU awards is not material. RSUs settle into shares of common stock upon vesting. Upon the vesting of the RSUs, we net-settle the RSUs and withhold a portion of the shares to satisfy minimum statutory employee withholding taxes. Total payment for the employees’ tax obligations to the taxing authorities is reflected as a financing activity within the condensed consolidated statements of cash flows. The following summarizes the number and value of the shares withheld for employee taxes (in thousands): Three Months Ended March 31, March 31, Shares withheld for taxes 343 221 Amount withheld for taxes $ 9,441 $ 6,600 Employee Stock Options The following table summarizes the weighted-average assumptions relating to our employee stock options: Three Months Ended March 31, March 31, Expected term in years 4.3 4.3 Volatility 43 % 40 % Risk-free interest rate 1.1 % 1.5 % 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, 2015 6,968 $ 20.03 Granted 1,161 23.83 Forfeited (49 ) 35.46 Exercised (906 ) 5.82 Balance—March 31, 2016 7,174 $ 22.33 Options vested and expected to vest—March 31, 2016 7,011 $ 22.17 3.37 $ 65,127 Options exercisable—March 31, 2016 5,107 $ 19.71 2.24 $ 56,011 The aggregate intrinsic value represents the pre-tax difference between the exercise price of stock options and the quoted market price of our common stock on March 31, 2016 , for all in-the-money options. As of March 31, 2016 , total compensation expense related to unvested stock options granted to employees but not yet recognized was $19.5 million . This expense is expected to be amortized on a straight-line basis over a weighted-average period of 3.4 years. Additional information related to our stock options is summarized below (in thousands, except per share amounts): Three Months Ended March 31, 2016 March 31, 2015 Weighted-average fair value per share granted $ 8.68 $ 11.17 Intrinsic value of options exercised 19,424 41,003 Fair value of options vested 2,084 3,792 Employee Stock Purchase Plan In determining the fair value of our ESPP, we use the Black-Scholes option pricing model that employs the following weighted-average assumptions: Three Months Ended March 31, March 31, Expected term in years 0.5 0.5 Volatility 48 % 28 % Risk-free interest rate 0.4 % 0.1 % Dividend rate — % — % Additional information related to the ESPP is provided below (in thousands, except per share amounts): Three Months Ended March 31, March 31, Weighted-average fair value per share granted $ 7.19 $ 7.56 Shares issued under the ESPP 614 427 Weighted-average price per share issued $ 20.49 $ 21.34 Stock-based Compensation Expense Stock-based compensation expense is included in costs and expenses as follows (in thousands): Three Months Ended March 31, March 31, Cost of product revenue $ 326 $ 140 Cost of service revenue 2,193 1,632 Research and development 7,355 5,157 Sales and marketing 17,114 9,307 General and administrative 3,893 2,686 Total stock-based compensation expense $ 30,881 $ 18,922 The following table summarizes stock-based compensation expense by award type (in thousands): Three Months Ended March 31, March 31, RSUs $ 27,082 $ 14,292 Stock options 1,954 3,455 ESPP 1,845 1,175 Total stock-based compensation expense $ 30,881 $ 18,922 Total income tax benefit associated with stock-based compensation that is recognized in the consolidated statements of operations is as follows (in thousands): Three Months Ended March 31, March 31, Income tax benefit associated with stock-based compensation $ 7,834 $ 3,377 Share Repurchase Program In January 2016, our board of directors approved a new Share Repurchase Program (the “Program”), which authorizes the repurchase of up to $200.0 million of our outstanding common stock through December 31, 2017. 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 the three months ended March 31, 2016 , we repurchased 2.0 million shares of common stock under the Program in open market transactions at an average price of $24.97 per share, for an aggregate purchase price of $50.0 million . As of March 31, 2016 , $150.0 million remains available for future share repurchases under the Program.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2016
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES Our effective tax rate was 35% for the three months ended March 31, 2016, compared to an effective tax rate of 5% for the same period last year. The effective tax rate for the periods presented was comprised of U.S. federal and state taxes, withholding taxes and foreign income taxes. The changes in the tax provision and effective tax rate were primarily because we had a pretax loss for the three months ended March 31, 2016, as compared to having a pretax income for the same period last year. Our effective tax rate for the three months ended March 31, 2016 included the tax benefit from the U.S. federal research and development (“R&D”) credit. The effective tax rate for the three months ended March 31, 2015 did not reflect the tax benefit of the U.S. federal R&D credit as it expired at the end of 2014 and was reinstated retroactively in December 2015. As of March 31, 2016 and December 31, 2015, unrecognized tax benefits were $63.4 million and $59.7 million , respectively. The total amount of $62.1 million in unrecognized tax benefits, if recognized, would favorably impact the effective tax rate. It is our policy to classify accrued interest and penalties related to unrecognized tax benefits in the provision for income taxes. As of March 31, 2016, we had accrued $6.7 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 2009. We are no longer subject to examination by U.S. federal tax authorities for tax years prior to 2012. We are currently under examination by U.S federal income tax authorities for the tax years 2012, 2013, and 2014.

Defined Contribution Plans

Defined Contribution Plans	3 Months Ended
	Mar. 31, 2016
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 of directors 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 for the three months ended March 31, 2016 and March 31, 2015 were $1.0 million and $0.8 million , respectively.

Segment and Significant Custome

Segment and Significant Customer Information	3 Months Ended
	Mar. 31, 2016
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 tables set forth revenue and property and equipment—net by geographic region (in thousands): Three Months Ended Revenue March 31, March 31, Americas: United States $ 75,558 $ 58,501 Canada 31,305 20,458 Other Americas 13,183 12,601 Total Americas 120,046 91,560 Europe, Middle East, and Africa (“EMEA”) 105,491 75,664 Asia Pacific (“APAC”) 59,039 45,662 Total revenue $ 284,576 $ 212,886 Property and Equipment — net March 31, December 31, Americas: United States $ 82,885 $ 61,064 Other Americas 9,021 8,972 Total Americas 91,906 70,036 EMEA: France 14,585 13,201 Other EMEA 5,244 3,977 Total EMEA 19,829 17,178 APAC 4,047 3,853 Total property and equipment—net $ 115,782 $ 91,067 The following customer, which is a distributor, accounted for 10% or more of our revenue: Three Months Ended March 31, March 31, Exclusive Networks Group 19 % 17 % The following customers, each of which is a distributor, accounted for 10% or more of net accounts receivable: March 31, December 31, Exclusive Networks Group 21 % 23 % Fine Tec Computers 13 % * * Represents less than 10%

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	3 Months Ended
	Mar. 31, 2016
Other Comprehensive Income (Loss), Net of Tax [Abstract]
ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) The following table summarizes the changes in accumulated balances of other comprehensive income or loss (in thousands): March 31, 2016 Unrealized Losses on Investments Tax benefit (provision) related to items of other comprehensive income or loss Total Beginning balance $ (1,437 ) $ 504 $ (933 ) Other comprehensive income (loss) before reclassifications 1,891 (662 ) 1,229 Amounts reclassified from accumulated other comprehensive income (loss) (3 ) 1 (2 ) Net current-period other comprehensive income (loss) 1,888 (661 ) 1,227 Ending balance $ 451 $ (157 ) $ 294 The following table provides details about the reclassification out of accumulated other comprehensive income (loss) (in thousands): Three Months Ended March 31, 2016 Details about Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income (Loss) Affected Line Item in the Statement Where Net Income is Presented Unrealized losses on investments $ (3 ) Other expense—net Tax benefit related to items of other comprehensive loss 1 Provision for income taxes Total reclassification for the period $ (2 )

Foreign Currency Derivatives

Foreign Currency Derivatives	3 Months Ended
	Mar. 31, 2016
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 United States is denominated in foreign currencies and is subject to fluctuations due to changes in foreign currency exchange rates, particularly changes in the Canadian dollar (“CAD”) and the Euro (“EUR”). To help protect against significant fluctuations in value and the volatility of future cash flows caused by changes in currency exchange rates, we engage in foreign currency risk management activities 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 between one and three months. Changes in the fair value of forward exchange contracts related to balance sheet accounts are insignificant and are included in Other expense—net in the condensed consolidated statement of operations. As of March 31, 2016 , the fair value of the forward exchange contracts was not material. Additionally, independent of any hedging activities, fluctuations in foreign currency exchange rates may cause us to recognize transaction gains and losses 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 the CAD, long-term material changes in the value of the U.S. dollar against other foreign currencies, such as the EUR, GBP and CNY could adversely impact our operating expenses in the future. The notional amount of forward exchange contracts to hedge balance sheet accounts as of March 31, 2016 and December 31, 2015 were (in thousands): Buy/Sell Notional Balance Sheet Contracts: Currency—As of March 31, 2016 CAD Sell $ 8,540 Currency—As of December 31, 2015 CAD Sell $ 7,011

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2016
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	RELATED PARTY TRANSACTIONS The son of one member of our board of directors is a partner of an outside law firm that we utilize for certain complex litigation matters. Expenses for legal services provided by the law firm related to matters that arose subsequent to the member joining our board of directors were $0.3 million and $1.9 million in the three months ended March 31, 2016 and March 31, 2015, respectively. Of such amounts, $0.2 million and $0.5 million were incurred under contingent fee arrangements in the three months ended March 31, 2016 and March 31, 2015, respectively. Amounts due and payable to the law firm were $0.4 million and $5.3 million as of March 31, 2016 and December 31, 2015 , respectively.

Summary of Significant Accoun24

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2016
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, 2015, contained in our Annual Report on Form 10-K (the “Form 10-K”) filed with the SEC on February 26, 2016. In the opinion of management, all adjustments, which includes normal recurring adjustments, considered necessary for a fair presentation have been included. All intercompany balances, transactions and cash flows have been eliminated. The results of operations for the three months ended March 31, 2016 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, 2015 is derived from the audited consolidated financial statements for the year ended December 31, 2015. The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. Actual results could differ materially from those estimates. There have been no material changes to our significant accounting policies as of and for the three months ended March 31, 2016.
Recent Accounting Pronouncements	Recently Adopted Accounting Standards In September 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2015-16—Business Combinations—Simplifying the Accounting for Measurement-Period Adjustments, which 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. We adopted ASU 2015-16 on January 1, 2016. The adoption of ASU 2015-16 did not have any impact on our consolidated financial statements. In April 2015, the FASB issued ASU 2015-05—Intangibles—Goodwill and Other—Internal—Use Software— Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement, which provides guidance on determining whether a cloud computing arrangement contains a software license. If a cloud computing arrangement includes a software license, then the customer should account for the software license element of the arrangement consistent with the acquisition of other software licenses. If a cloud computing arrangement does not include a software license, the customer should account for the arrangement as a service contract. We adopted ASU 2015-05 on a prospective basis beginning on January 1, 2016. The impact of ASU 2015-05 did not have a significant impact on our consolidated financial statements. In February 2015, the FASB issued ASU 2015-02—Consolidation—Amendments to the Consolidation Analysis, which updates the accounting guidance on consolidation requirements. This update changes the guidance with respect to the analysis that a reporting entity must perform to determine whether it should consolidate certain types of legal entities. ASU 2015-02 also makes several modifications to the consolidation guidance for variable interest entities (“VIEs”). We adopted ASU 2015-02 on January 1, 2016. The adoption of ASU 2015-02 did not have any impact on our consolidated financial statements. Recent Accounting Standards Not Yet Effective In March 2016, the FASB issued ASU 2016-09—Compensation—Stock Compensation—Improvements to Employee Share-Based Payment Accounting, which changes certain aspects of accounting for shared-based payments to employees. The new guidance will require all income tax effects of awards to be recognized in the income statement for the period in which the awards vest or are settled. It also allows an employer to repurchase more of an employee’s shares for tax withholding purposes without triggering liability accounting and to make a policy election to account for forfeitures as they occur. This new guidance will be effective for us beginning on January 1, 2017, and interim periods within those fiscal years. Early adoption is permitted in any annual or interim period for which financial statements have not been issued or made available for issuance, but all of the guidance must be adopted in the same period. We are currently evaluating the impact ASU 2016-09 will have on our consolidated financial statements. In February 2016, the FASB issued ASU 2016-02—Leases, which amends lease accounting requirements to begin recording assets and liabilities arising from leases on the balance sheet. The new guidance will also require significant additional disclosures about the amount, timing and uncertainty of cash flows from leases. This new guidance will be effective for us beginning on January 1, 2019 using a modified retrospective approach. The modified retrospective approach includes a number of optional practical expedients that entities may elect to apply. We are currently evaluating the impact ASU 2016-02 will have on our consolidated financial statements. In January 2016, the FASB issued ASU 2016-01—Financial Instruments—Overall—Recognition and Measurement of Financial Assets and Financial Liabilities, which modifies how entities measure equity investments and present changes in the fair value of financial liabilities. Under the new guidance, entities will have to measure equity investments that do not result in consolidation and are not accounted under the equity method at fair value and recognize any changes in fair value in net income unless the investments qualify for the new practicality exception. The practicality exception will apply to those equity investments that do not have a readily determinable fair value and do not qualify for the practical expedient to estimate fair value, and as such these investments may be measured at cost. ASU 2016-01 will be effective for us beginning on January 1, 2018. We do not expect the impact of ASU 2016-01 on our consolidated financial statements to be significant. In July 2015, the FASB issued ASU 2015-11—Inventory—Simplifying the Measurement of Inventory, which changes the measurement principle for inventory from the lower of cost or market to lower of cost and net realizable value. ASU 2015-11 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 or 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 ASU 2014-09—Revenue from Contracts with Customers, which creates 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. In March 2016, the FASB issued ASU 2016-08, which clarifies the implementation guidance on principal versus agent considerations. In April 2016, the FASB issued ASU 2016-10, which clarifies the implementation guidance on identifying performance obligations and licensing. These standards 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 these new standards on our consolidated financial statements.

Financial Instruments and Fai25

Financial Instruments and Fair Value (Tables)	3 Months Ended
	Mar. 31, 2016
Financial Instruments and Fair Value [Abstract]
Summary of Investments	The following table summarizes our investments as of March 31, 2016 and December 31, 2015 (in thousands): March 31, 2016 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Corporate debt securities $ 410,265 $ 574 $ (250 ) $ 410,589 Commercial paper 75,465 7 (8 ) 75,464 Municipal bonds 54,198 53 (7 ) 54,244 Certificates of deposit and term deposits (1) 19,847 — — 19,847 U.S. government and agency securities 66,253 82 — 66,335 Total available-for-sale securities $ 626,028 $ 716 $ (265 ) $ 626,479 December 31, 2015 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Corporate debt securities $ 438,533 $ 30 $ (1,369 ) $ 437,194 Commercial paper 66,263 3 (34 ) 66,232 Municipal bonds 61,050 12 (40 ) 61,022 Certificates of deposit and term deposits (1) 14,897 — — 14,897 U.S. government and agency securities 41,727 3 (42 ) 41,688 Total available-for-sale securities $ 622,470 $ 48 $ (1,485 ) $ 621,033 (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 March 31, 2016 and December 31, 2015 (in thousands): March 31, 2016 Less Than 12 Months 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Corporate debt securities $ 141,018 $ (159 ) $ 50,269 $ (91 ) $ 191,287 $ (250 ) Commercial paper 16,754 (8 ) — — 16,754 (8 ) Municipal bonds 12,710 (6 ) 1,006 (1 ) 13,716 (7 ) Total available-for-sale securities $ 170,482 $ (173 ) $ 51,275 $ (92 ) $ 221,757 $ (265 ) December 31, 2015 Less Than 12 Months 12 Months or Greater Total Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses Corporate debt securities $ 348,534 $ (1,187 ) $ 42,033 $ (182 ) $ 390,567 $ (1,369 ) Commercial paper 31,977 (34 ) — — 31,977 (34 ) Municipal bonds 41,677 (36 ) 1,008 (4 ) 42,685 (40 ) U.S. government and agency securities 34,703 (42 ) — — 34,703 (42 ) Total available-for-sale securities $ 456,891 $ (1,299 ) $ 43,041 $ (186 ) $ 499,932 $ (1,485 )
Investments Classified by Contractual Maturity Date	The contractual maturities of our investments as of March 31, 2016 and December 31, 2015 were as follows (in thousands): March 31, December 31, Due within one year $ 384,591 $ 348,074 Due within one to three years 241,888 272,959 Total $ 626,479 $ 621,033
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 March 31, 2016 and December 31, 2015 (in thousands): March 31, 2016 December 31, 2015 Aggregate Fair Value Quoted Prices in Active Markets For Identical Assets Significant Other Observable Remaining Inputs Significant Other Unobservable Remaining Inputs Aggregate Fair Value Quoted Prices in Active Markets For Identical Assets Significant Other Observable Remaining Inputs Significant Other Unobservable Remaining Inputs (Level 1) (Level 2) (Level 3) (Level 1) (Level 2) (Level 3) Assets: Corporate debt securities $ 410,589 $ — $ 410,589 $ — $ 437,194 $ — $ 437,194 $ — Commercial paper 82,962 — 82,962 — 69,231 — 69,231 — Municipal bonds 54,244 — 54,244 — 61,022 — 61,022 — Certificates of deposit and term deposits 19,847 — 19,847 — 14,897 — 14,897 — Money market funds 48,599 48,599 — — 50,030 50,030 — — U.S. government and agency securities 66,335 50,326 16,009 — 41,688 25,693 15,995 — Total $ 682,576 $ 98,925 $ 583,651 $ — $ 674,062 $ 75,723 $ 598,339 $ — Reported as: Cash equivalents $ 56,097 $ 53,029 Short-term investments 384,591 348,074 Long-term investments 241,888 272,959 Total $ 682,576 $ 674,062

Inventory (Tables)

Inventory (Tables)	3 Months Ended
	Mar. 31, 2016
Inventory Disclosure [Abstract]
Inventory	Inventory consisted of the following as of March 31, 2016 and December 31, 2015 (in thousands): March 31, December 31, Raw materials $ 15,270 $ 15,425 Finished goods 62,969 68,443 Inventory $ 78,239 $ 83,868

Property and Equipment_Net (Tab

Property and Equipment—Net (Tables)	3 Months Ended
	Mar. 31, 2016
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property and equipment—net as of March 31, 2016 and December 31, 2015 consisted of the following (in thousands): March 31, December 31, Land $ 30,321 $ 21,683 Building and building improvements 39,454 28,841 Evaluation units 18,413 15,784 Computer equipment and software 49,701 45,632 Furniture and fixtures 10,536 8,901 Construction-in-progress 8,796 8,106 Leasehold improvements 13,182 11,179 Total property and equipment 170,403 140,126 Less: accumulated depreciation (54,621 ) (49,059 ) Property and equipment—net $ 115,782 $ 91,067

Business Combinations (Tables)

Business Combinations (Tables)	3 Months Ended
	Mar. 31, 2016
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 Purchase Price Allocation	Total allocation of the purchase price was as follows (in thousands): Cash and cash equivalents $ 3,268 Accounts receivable 8,191 Inventory 11,610 Prepaid expenses and other assets 2,409 Property and equipment 920 Deferred tax assets 18,585 Identifiable intangible assets 19,600 Goodwill 1,868 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

Goodwill and Other Intangible29

Goodwill and Other Intangible Assets - Net (Tables)	3 Months Ended
	Mar. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets by Major Class	The following tables present other intangible assets—net as of March 31, 2016 and December 31, 2015 (in thousands): March 31, 2016 Weighted-Average Useful Life (in Years) Gross Accumulated Amortization Net Other intangible assets—net: Customer relationships 5.0 $ 12,200 $ 1,830 $ 10,370 Developed technologies and other 3.6 11,384 5,297 6,087 Total other intangible assets—net $ 23,584 $ 7,127 $ 16,457 December 31, 2015 Weighted-Average Useful Life (in Years) Gross Accumulated Amortization Net Other intangible assets—net: Customer relationships 5.0 $ 12,200 $ 1,220 $ 10,980 Developed technologies and other 3.6 11,384 4,724 6,660 Total other intangible assets—net $ 23,584 $ 5,944 $ 17,640
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The following table summarizes estimated future amortization expense of Other intangible assets—net (in thousands): Amount Years: 2016 (remainder) $ 3,417 2017 4,240 2018 4,240 2019 3,340 2020 1,220 Total $ 16,457

Net Income (Loss) Per Share (Ta

Net Income (Loss) Per Share (Tables)	3 Months Ended
	Mar. 31, 2016
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 (loss) per share is as follows (in thousands, except per share amounts): Three Months Ended March 31, March 31, Numerator: Net income (loss) $ (3,429 ) $ 1,560 Denominator: Basic shares: Weighted-average common stock outstanding-basic 171,745 168,077 Diluted shares: Weighted-average common stock outstanding-basic 171,745 168,077 Effect of potentially dilutive securities: Stock options — 3,837 RSUs (including PSUs) — 1,741 ESPP — 65 Weighted-average shares used to compute diluted net income per share 171,745 173,720 Net income (loss) per share: Basic $ (0.02 ) $ 0.01 Diluted $ (0.02 ) $ 0.01
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following potentially dilutive shares of common stock were excluded from the computation of diluted net income (loss) per share for the periods presented, as their effect would have been antidilutive (in thousands): Three Months Ended March 31, March 31, Stock options 6,939 249 RSUs (including PSUs) 10,020 1,333 ESPP 282 169 17,241 1,751

Restructuring Charges (Tables)

Restructuring Charges (Tables)	3 Months Ended
	Mar. 31, 2016
Restructuring and Related Activities [Abstract]
Summary of Restructuring Activity	The following table provides a summary of restructuring activity as of March 31, 2016 (in thousands): Employee Severance and Other Benefits Contract Terminations and Other Charges Total Balance as of December 31, 2015 $ 3,689 $ 229 $ 3,918 Costs incurred 328 — 328 Less cash payments (1,282 ) (125 ) (1,407 ) Less non-cash charges (89 ) — (89 ) Balance as of March 31, 2016 $ 2,646 $ 104 $ 2,750

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Contractual Obligation, Fiscal Year Maturity Schedule	The following table summarizes our future principal contractual obligations as of March 31, 2016 (in thousands): Total 2016 (remainder) 2017 2018 2019 2020 Thereafter Operating lease commitments $ 60,677 $ 13,411 $ 12,897 $ 11,036 $ 8,734 $ 5,945 $ 8,654 Inventory purchase commitments 77,530 77,530 — — — — — Other contractual commitments and open purchase orders 49,048 41,207 3,461 1,590 930 930 930 Total $ 187,255 $ 132,148 $ 16,358 $ 12,626 $ 9,664 $ 6,875 $ 9,584
Schedule of Product Warranty Liability	Accrued warranty activities are summarized as follows (in thousands): Three Months Ended March 31, March 31, Accrued warranty balance—beginning of the period $ 3,144 $ 4,269 Warranty costs incurred (511 ) (1,095 ) Provision for warranty for the period 377 945 Adjustment related to pre-existing warranties (353 ) 222 Accrued warranty balance—end of the period $ 2,657 $ 4,341

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Compensation, Restricted Stock Units Award Activity	The following table summarizes the activity and related information for RSUs, including PSUs, 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, 2015 9,257 $ 32.97 Granted 2,831 23.87 Forfeited (441 ) 31.94 Vested (1,014 ) 28.45 Balance—March 31, 2016 10,633 $ 30.86 RSUs expected to vest—March 31, 2016 9,959 $ 30.71
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 March 31, March 31, Shares withheld for taxes 343 221 Amount withheld for taxes $ 9,441 $ 6,600
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions And Allocation of Recognized Period Costs	The following table summarizes the weighted-average assumptions relating to our employee stock options: Three Months Ended March 31, March 31, Expected term in years 4.3 4.3 Volatility 43 % 40 % Risk-free interest rate 1.1 % 1.5 % 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, 2015 6,968 $ 20.03 Granted 1,161 23.83 Forfeited (49 ) 35.46 Exercised (906 ) 5.82 Balance—March 31, 2016 7,174 $ 22.33 Options vested and expected to vest—March 31, 2016 7,011 $ 22.17 3.37 $ 65,127 Options exercisable—March 31, 2016 5,107 $ 19.71 2.24 $ 56,011
Schedule of Share-based Compensation, Stock Options, Activity, Additional Information	Additional information related to our stock options is summarized below (in thousands, except per share amounts): Three Months Ended March 31, 2016 March 31, 2015 Weighted-average fair value per share granted $ 8.68 $ 11.17 Intrinsic value of options exercised 19,424 41,003 Fair value of options vested 2,084 3,792
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 March 31, March 31, Expected term in years 0.5 0.5 Volatility 48 % 28 % Risk-free interest rate 0.4 % 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 March 31, March 31, Weighted-average fair value per share granted $ 7.19 $ 7.56 Shares issued under the ESPP 614 427 Weighted-average price per share issued $ 20.49 $ 21.34
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 March 31, March 31, Cost of product revenue $ 326 $ 140 Cost of service revenue 2,193 1,632 Research and development 7,355 5,157 Sales and marketing 17,114 9,307 General and administrative 3,893 2,686 Total stock-based compensation expense $ 30,881 $ 18,922
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 March 31, March 31, RSUs $ 27,082 $ 14,292 Stock options 1,954 3,455 ESPP 1,845 1,175 Total stock-based compensation expense $ 30,881 $ 18,922
Income Tax Benefit from Stock Option Plans	Total income tax benefit associated with stock-based compensation that is recognized in the consolidated statements of operations is as follows (in thousands): Three Months Ended March 31, March 31, Income tax benefit associated with stock-based compensation $ 7,834 $ 3,377

Segment and Significant Custo34

Segment and Significant Customer Information (Tables)	3 Months Ended
	Mar. 31, 2016
Segment Reporting [Abstract]
Revenue from external customers by geographic region	Three Months Ended Revenue March 31, March 31, Americas: United States $ 75,558 $ 58,501 Canada 31,305 20,458 Other Americas 13,183 12,601 Total Americas 120,046 91,560 Europe, Middle East, and Africa (“EMEA”) 105,491 75,664 Asia Pacific (“APAC”) 59,039 45,662 Total revenue $ 284,576 $ 212,886
Property and equipment by geographic region	Property and Equipment — net March 31, December 31, Americas: United States $ 82,885 $ 61,064 Other Americas 9,021 8,972 Total Americas 91,906 70,036 EMEA: France 14,585 13,201 Other EMEA 5,244 3,977 Total EMEA 19,829 17,178 APAC 4,047 3,853 Total property and equipment—net $ 115,782 $ 91,067
Schedule of Revenue by Major Customers	The following customer, which is a distributor, accounted for 10% or more of our revenue: Three Months Ended March 31, March 31, Exclusive Networks Group 19 % 17 %
Schedule of Accounts Receivable by Major Customers	The following customers, each of which is a distributor, accounted for 10% or more of net accounts receivable: March 31, December 31, Exclusive Networks Group 21 % 23 % Fine Tec Computers 13 % * * Represents less than 10%

Accumulated Other Comprehensi35

Accumulated Other Comprehensive Income (Loss) (Tables)	3 Months Ended
	Mar. 31, 2016
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	The following table summarizes the changes in accumulated balances of other comprehensive income or loss (in thousands): March 31, 2016 Unrealized Losses on Investments Tax benefit (provision) related to items of other comprehensive income or loss Total Beginning balance $ (1,437 ) $ 504 $ (933 ) Other comprehensive income (loss) before reclassifications 1,891 (662 ) 1,229 Amounts reclassified from accumulated other comprehensive income (loss) (3 ) 1 (2 ) Net current-period other comprehensive income (loss) 1,888 (661 ) 1,227 Ending balance $ 451 $ (157 ) $ 294
Reclassification out of Accumulated Other Comprehensive Income (Loss)	The following table provides details about the reclassification out of accumulated other comprehensive income (loss) (in thousands): Three Months Ended March 31, 2016 Details about Accumulated Other Comprehensive Income Components Amount Reclassified from Accumulated Other Comprehensive Income (Loss) Affected Line Item in the Statement Where Net Income is Presented Unrealized losses on investments $ (3 ) Other expense—net Tax benefit related to items of other comprehensive loss 1 Provision for income taxes Total reclassification for the period $ (2 )

Foreign Currency Derivatives (T

Foreign Currency Derivatives (Tables)	3 Months Ended
	Mar. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Notional Amounts of Outstanding Derivative Positions	The notional amount of forward exchange contracts to hedge balance sheet accounts as of March 31, 2016 and December 31, 2015 were (in thousands): Buy/Sell Notional Balance Sheet Contracts: Currency—As of March 31, 2016 CAD Sell $ 8,540 Currency—As of December 31, 2015 CAD Sell $ 7,011

Financial Instruments and Fai37

Financial Instruments and Fair Value , Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 626,028	$ 622,470
Unrealized Gains	716	48
Unrealized Losses	(265)	(1,485)
Fair Value	626,479	621,033
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	170,482	456,891
Less Than 12 Months, Unrealized Losses	(173)	(1,299)
12 Months or Greater, Fair Value	51,275	43,041
12 Months or Greater, Unrealized Losses	(92)	(186)
Total, Fair Value	221,757	499,932
Total, Unrealized Losses	(265)	(1,485)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Due within one year	384,591	348,074
Due within one to three years	241,888	272,959
Fair Value	626,479	621,033
Corporate debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	410,265	438,533
Unrealized Gains	574	30
Unrealized Losses	(250)	(1,369)
Fair Value	410,589	437,194
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	141,018	348,534
Less Than 12 Months, Unrealized Losses	(159)	(1,187)
12 Months or Greater, Fair Value	50,269	42,033
12 Months or Greater, Unrealized Losses	(91)	(182)
Total, Fair Value	191,287	390,567
Total, Unrealized Losses	(250)	(1,369)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	410,589	437,194
Commercial paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	75,465	66,263
Unrealized Gains	7	3
Unrealized Losses	(8)	(34)
Fair Value	75,464	66,232
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	16,754	31,977
Less Than 12 Months, Unrealized Losses	(8)	(34)
12 Months or Greater, Fair Value	0	0
12 Months or Greater, Unrealized Losses	0	0
Total, Fair Value	16,754	31,977
Total, Unrealized Losses	(8)	(34)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	75,464	66,232
Municipal bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	54,198	61,050
Unrealized Gains	53	12
Unrealized Losses	(7)	(40)
Fair Value	54,244	61,022
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	12,710	41,677
Less Than 12 Months, Unrealized Losses	(6)	(36)
12 Months or Greater, Fair Value	1,006	1,008
12 Months or Greater, Unrealized Losses	(1)	(4)
Total, Fair Value	13,716	42,685
Total, Unrealized Losses	(7)	(40)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	54,244	61,022
Certificates of deposit and term deposits [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	19,847	14,897
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	19,847	14,897
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	19,847	14,897
U.S. government and agency securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	66,253	41,727
Unrealized Gains	82	3
Unrealized Losses	0	(42)
Fair Value	66,335	41,688
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value		34,703
Less Than 12 Months, Unrealized Losses		(42)
12 Months or Greater, Fair Value		0
12 Months or Greater, Unrealized Losses		0
Total, Fair Value		34,703
Total, Unrealized Losses		(42)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	$ 66,335	$ 41,688

Financial Instruments and Fai38

Financial Instruments and Fair Value , Fair Value Measurements (Details) - Recurring [Member] - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Estimate of Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	$ 682,576	$ 674,062
Estimate of Fair Value [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	98,925	75,723
Estimate of Fair Value [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	583,651	598,339
Estimate of Fair Value [Member] | Corporate debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	410,589	437,194
Estimate of Fair Value [Member] | Corporate debt securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	0	0
Estimate of Fair Value [Member] | Corporate debt securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	410,589	437,194
Estimate of Fair Value [Member] | Commercial paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	82,962	69,231
Estimate of Fair Value [Member] | Commercial paper [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	0	0
Estimate of Fair Value [Member] | Commercial paper [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	82,962	69,231
Estimate of Fair Value [Member] | Municipal bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	54,244	61,022
Estimate of Fair Value [Member] | Municipal bonds [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	0	0
Estimate of Fair Value [Member] | Municipal bonds [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	54,244	61,022
Estimate of Fair Value [Member] | Certificates of deposit and term deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	19,847	14,897
Estimate of Fair Value [Member] | Certificates of deposit and term deposits [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	0	0
Estimate of Fair Value [Member] | Certificates of deposit and term deposits [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	19,847	14,897
Estimate of Fair Value [Member] | Money market funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	48,599	50,030
Estimate of Fair Value [Member] | Money market funds [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	48,599	50,030
Estimate of Fair Value [Member] | Money market funds [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	0	0
Estimate of Fair Value [Member] | U.S. government and agency securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	66,335	41,688
Estimate of Fair Value [Member] | U.S. government and agency securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	50,326	25,693
Estimate of Fair Value [Member] | U.S. government and agency securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	16,009	15,995
Reported as [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	682,576	674,062
Reported as [Member] | Cash equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	56,097	53,029
Reported as [Member] | Short-term investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	384,591	348,074
Reported as [Member] | Long-term investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities, Fair Value Disclosure	$ 241,888	$ 272,959

Inventory (Details)

Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Inventory, Net [Abstract]
Raw materials	$ 15,270	$ 15,425
Finished goods	62,969	68,443
Inventory	78,239	83,868
Finished goods held by distributors	900	1,100
Materials at contract manufacturers	$ 4,900	$ 4,900

Property and Equipment_Net (Det

Property and Equipment—Net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	$ 170,403		$ 140,126
Less: accumulated depreciation	(54,621)		(49,059)
Property and equipment - net	115,782		91,067
Depreciation expense	9,400	$ 6,000
Land [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	30,321		21,683
Building and building improvements [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	39,454		28,841
Evaluation units [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	18,413		15,784
Computer equipment and software [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	49,701		45,632
Furniture and fixtures [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	10,536		8,901
Construction-in-progress [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	8,796		8,106
Leasehold improvements [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	13,182		$ 11,179
CALIFORNIA
Property, Plant and Equipment, Net, by Type [Abstract]
Payments to acquire certain real property	18,500
CALIFORNIA | Land [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Payments to acquire certain real property	8,700
CALIFORNIA | Building [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Payments to acquire certain real property	$ 9,800

Investments in Privately-Held41

Investments in Privately-Held Companies (Details) $ in Millions	Mar. 31, 2016USD ($)privately_held_company	Dec. 31, 2015USD ($)privately_held_company
Investments, All Other Investments [Abstract]
Number of privately-held companies | privately_held_company	3	3
Investments in equity securities of privately-held companies | $	$ 10.3	$ 10.3

Business Combinations , Additio

Business Combinations , Additional Information (Details) - USD ($) $ in Thousands	Jul. 08, 2015	Mar. 31, 2016	Dec. 31, 2015
Business Acquisition [Line Items]
Goodwill		$ 4,692	$ 4,692
Meru Networks, Inc. [Member]
Business Acquisition [Line Items]
Cash consideration	$ 40,914
Withholding tax liability	379
Goodwill	1,868
General and administrative [Member] | Meru Networks, Inc. [Member]
Business Acquisition [Line Items]
Acquisition-related costs	$ 1,700
Restricted Stock Units (RSUs) [Member] | Meru Networks, Inc. [Member]
Business Acquisition [Line Items]
Fortinet RSUs issued for conversion of Meru RSUs	53,401

Business Combinations , Purchas

Business Combinations , Purchase Price (Details) - Meru Networks, Inc. [Member] $ in Thousands	Jul. 08, 2015USD ($)
Business Acquisition [Line Items]
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 , Purch44

Business Combinations , Purchase Price Allocations (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Jul. 08, 2015
Business Acquisition [Line Items]
Goodwill	$ 4,692	$ 4,692
Meru Networks, Inc. [Member]
Business Acquisition [Line Items]
Cash and cash equivalents			$ 3,268
Accounts receivable			8,191
Inventory			11,610
Prepaid expenses and other assets			2,409
Property and equipment			920
Deferred tax assets			18,585
Identifiable intangible assets			19,600
Goodwill			1,868
Total assets acquired			66,451
Deferred revenue			9,800
Accounts payable and accrued liabilities			14,887
Total liabilities assumed			24,687
Total purchase price			$ 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	5 years
Fair values	$ 12,200
Developed Technologies [Member]
Business Acquisition [Line Items]
Estimated useful life	4 years
Fair values	$ 7,200
Trade Name [Member]
Business Acquisition [Line Items]
Estimated useful life	6 months
Fair values	$ 200

Goodwill and Other Intangible46

Goodwill and Other Intangible Assets - Net (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 4,692,000		$ 4,692,000
Impairments to goodwill	0
Finite-Lived Intangible Assets, Net [Abstract]
Gross	23,584,000		23,584,000
Accumulated Amortization	7,127,000		5,944,000
Total	16,457,000		$ 17,640,000
Amortization expense	$ 1,200,000	$ 300,000
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted average useful life	5 years		5 years
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 12,200,000		$ 12,200,000
Accumulated Amortization	1,830,000		1,220,000
Total	$ 10,370,000		$ 10,980,000
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Weighted average useful life	3 years 6 months 29 days		3 years 7 months 21 days
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 11,384,000		$ 11,384,000
Accumulated Amortization	5,297,000		4,724,000
Total	$ 6,087,000		$ 6,660,000

Goodwill and Other Intangible47

Goodwill and Other Intangible Assets - Net - Estimated Future Amortization Expense (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Fiscal Years:
2,016	$ 3,417
2,017	4,240
2,018	4,240
2,019	3,340
2,020	1,220
Total	$ 16,457	$ 17,640

Net Income (Loss) Per Share , C

Net Income (Loss) Per Share , Calculation of Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Earnings Per Share [Line Items]
Net income (loss)	$ (3,429)	$ 1,560
Basic shares:
Weighted-average common shares outstanding-basic (in shares)	171,745	168,077
Diluted shares:
Weighted-average common shares outstanding-basic (in shares)	171,745	168,077
Effect of potentially dilutive securities:
Weighted-average shares used to compute diluted net income per share (in shares)	171,745	173,720
Net income (loss) per share:
Basic (in dollars per share)	$ (0.02)	$ 0.01
Diluted (in dollars per share)	$ (0.02)	$ 0.01
Stock Options [Member]
Effect of potentially dilutive securities:
Employee stock options and purchase rights (in shares)	0	3,837
RSUs (including PSUs) [Member]
Effect of potentially dilutive securities:
Employee stock options and purchase rights (in shares)	0	1,741
ESPP [Member]
Effect of potentially dilutive securities:
Employee stock options and purchase rights (in shares)	0	65

Net Income (Loss) Per Share , A

Net Income (Loss) Per Share , Anti Dilutive Securities (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	17,241	1,751
Stock Options [Member] | Stock Compensation Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	6,939	249
RSUs (including PSUs) [Member] | Stock Compensation Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	10,020	1,333
ESPP [Member] | Stock Compensation Plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	282	169

Restructuring Charges , Additio

Restructuring Charges , Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 328	$ 0
Restructuring charges incurred to date	7,900
Restructuring reserve	2,750		$ 3,918
Accrued Liabilities [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	2,500
Other Liabilities [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	200
Minimum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges expected	8,000
Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges expected	$ 8,500

Restructuring Charges , Restruc

Restructuring Charges , Restructuring Activity (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Restructuring Cost and Reserve [Line Items]
Balance, beginning	$ 3,918
Costs incurred	328	$ 0
Less cash payments	(1,407)
Less non-cash charges	(89)
Balance, ending	2,750
Employee Severance and Other Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Balance, beginning	3,689
Costs incurred	328
Less cash payments	(1,282)
Less non-cash charges	(89)
Balance, ending	2,646
Contract Terminations and Other Charges [Member]
Restructuring Cost and Reserve [Line Items]
Balance, beginning	229
Costs incurred	0
Less cash payments	(125)
Less non-cash charges	0
Balance, ending	$ 104

Commitments and Contingencies52

Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Rent expense	$ 4,600	$ 3,100
Inventory purchase commitments	77,530
Other contractual commitments and open purchase orders	$ 49,048

Commitments and Contingencies M

Commitments and Contingencies Minimum Operating Lease Payments (Details) $ in Thousands	Mar. 31, 2016USD ($)
Operating Lease Commitments:
Operating lease commitments, 2016 (remainder)	$ 13,411
Operating lease commitments, 2017	12,897
Operating lease commitments, 2018	11,036
Operating lease commitments, 2019	8,734
Operating lease commitments, 2020	5,945
Operating lease commitments, Thereafter	8,654
Operating lease commitments	60,677
Inventory purchase commitments:
Inventory purchase commitments, 2016 (remainder)	77,530
Inventory purchase commitments, 2017	0
Inventory purchase commitments, 2018	0
Inventory purchase commitments, 2019	0
Inventory purchase commitments, 2020	0
Inventory purchase commitments, Thereafter	0
Inventory purchase commitments	77,530
Other contractual commitments and open purchase orders:
Other contractual commitments and open purchase orders, 2016 (remainder)	41,207
Other contractual commitments and open purchase orders, 2017	3,461
Other contractual commitments and open purchase orders, 2018	1,590
Other contractual commitments and open purchase orders, 2019	930
Other contractual commitments and open purchase orders, 2020	930
Other contractual commitments and open purchase orders, Thereafter	930
Other contractual commitments and open purchase orders	49,048
Contractual Obligation	187,255
Contractual Obligation, 2016 (remainder)	132,148
Contractual Obligation, 2017	16,358
Contractual Obligation, 2018	12,626
Contractual Obligation, 2019	9,664
Contractual Obligation, 2020	6,875
Contractual Obligation, Thereafter	$ 9,584

Commitments and Contingencies ,

Commitments and Contingencies , Warranties (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Movement in Standard Product Warranty Accrual [Roll Forward]
Accrued warranty balance—beginning of the period	$ 3,144	$ 4,269
Warranty costs incurred	(511)	(1,095)
Provision for warranty for the period	377	945
Adjustment related to pre-existing warranties	(353)	222
Accrued warranty balance—end of the period	$ 2,657	$ 4,341

Stockholders' Equity , Restrict

Stockholders' Equity , Restricted Stock Units Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Amount withheld for taxes	$ 9,441	$ 6,600
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	9,257,000
Granted	2,831,000
Forfeited	(441,000)
Vested	(1,014,000)
Balance, ending	10,633,000
RSUs expected to vest—March 31, 2016	9,959,000
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	$ 32.97
Granted, weighted-average grant-date fair value per share (in dollars per share)	23.87
Forfeited, weighted-average grant-date fair value per share (in dollars per share)	31.94
Vested, weighted-average grant-date fair value per share (in dollars per share)	28.45
Balance, weighted-average grant-date fair value per share (in dollars per share)—ending	30.86
RSUs expected to vest, weighted-average grant-date fair value per share (in dollars per share)—ending	$ 30.71
Compensation cost not yet recognized	$ 303,800
Compensation cost not yet recognized period of recognition	3 years
Shares withheld for taxes	343,000	221,000
Amount withheld for taxes	$ 9,441	$ 6,600
Performance Stock Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Granted	0

Stockholders' Equity , Employee

Stockholders' Equity , Employee Stock Options Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining shares available for grant under the plans	45,616,141
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected term in years	4 years 3 months 26 days	4 years 3 months 26 days
Volatility	43.00%	40.00%
Risk-free interest rate	1.10%	1.50%
Dividend rate	0.00%	0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Balance - Beginning (in shares)	6,968,000
Granted (in shares)	1,161,000
Forfeited (in shares)	(49,000)
Exercised (in shares)	(906,000)
Balance - Ending (in shares)	7,174,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Balance - Beginning (in dollars per share)	$ 20.03
Granted (in dollars per share)	23.83
Forfeited (in dollars per share)	35.46
Exercised (in dollars per share)	5.82
Balance - Ending (in dollars per share)	$ 22.33
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options vested and expected to vest, Outstanding (in shares)	7,011,000
Options vested and expected to vest, Weighted average exercise price (in dollars per share)	$ 22.17
Options vested and expected to vest, Weighted average remaining contractual life (in years)	3 years 4 months 14 days
Options vested and expected to vest, Aggregate intrinsic value	$ 65,127
Options exercisable, Outstanding (in shares)	5,107,000
Options exercisable, Weighted average exercise price (in dollars per share)	$ 19.71
Options exercisable, Weighted average remaining contractual life (in years)	2 years 2 months 26 days
Options exercisable, Aggregate intrinsic value	$ 56,011
Compensation cost not yet recognized	$ 19,500
Compensation cost not yet recognized period of recognition	3 years 4 months 11 days
Weighted-average fair value per share granted	$ 8.68	$ 11.17
Intrinsic value of options exercised	$ 19,424	$ 41,003
Total fair value of awards vested	$ 2,084	$ 3,792

Stockholders' Equity , ESPP Inf

Stockholders' Equity , ESPP Information (Details) - Employee Stock Purchase Plan [Member] - $ / shares shares in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term in years	5 months 27 days	6 months
Volatility	48.00%	28.00%
Risk-free interest rate	0.40%	0.10%
Dividend rate	0.00%	0.00%
Weighted-average fair value per share granted (in dollars per share)	$ 7.19	$ 7.56
Shares issued under the ESPP (in shares)	614	427
Weighted-average price per share issued (in dollars per share)	$ 20.49	$ 21.34

Stockholders' Equity , Allocati

Stockholders' Equity , Allocation of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 30,881	$ 18,922
Income tax benefit associated with stock-based compensation	7,834	3,377
Cost of product revenue [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	326	140
Cost of services and other revenue [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	2,193	1,632
Research and development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	7,355	5,157
Selling and marketing [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	17,114	9,307
General and administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	3,893	2,686
RSUs [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	27,082	14,292
Stock Options [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	1,954	3,455
ESPP [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 1,845	$ 1,175

Stockholders' Equity , Share Re

Stockholders' Equity , Share Repurchase Program (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2016	Jan. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program, unused balance	$ 150
Share Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program, authorized amount		$ 200
Stock repurchased in the period, shares	2
Stock repurchased in the period, average price, per share	$ 24.97
Stock repurchased in the period, value	$ 50

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Effective income tax rate (percent)	35.00%	5.00%
Unrecognized tax benefits	$ 63.4		$ 59.7
Unrecognized tax benefits that would favoraby affect effective tax rate	62.1
Accrued estimated interest related to uncertain tax positions	$ 6.7

Defined Contribution Plans (Det

Defined Contribution Plans (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Matching contribution on employee contributions, Percent	50.00%
Maximum contribution percentage of each employee's eligible earnings, Percent	4.00%
Matching contributions to the 401(k) and RRSP Plans	$ 1	$ 0.8

Segment and Significant Custo62

Segment and Significant Customer Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016USD ($)Segment_Managersbusiness_activityoperating_segmentreportable_segment	Mar. 31, 2015USD ($)	Dec. 31, 2015USD ($)
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	$ 284,576	$ 212,886
Property and equipment - net	115,782		$ 91,067
Americas [Member]
Segment Reporting Information [Line Items]
Revenue	120,046	91,560
Property and equipment - net	91,906		70,036
United States
Segment Reporting Information [Line Items]
Revenue	75,558	58,501
Property and equipment - net	82,885		61,064
Canada [Member]
Segment Reporting Information [Line Items]
Revenue	31,305	20,458
Other Americas [Member]
Segment Reporting Information [Line Items]
Revenue	13,183	12,601
Property and equipment - net	9,021		8,972
EMEA [Member]
Segment Reporting Information [Line Items]
Revenue	105,491	75,664
Property and equipment - net	19,829		17,178
France [Member]
Segment Reporting Information [Line Items]
Property and equipment - net	14,585		13,201
Other EMEA [Member]
Segment Reporting Information [Line Items]
Property and equipment - net	5,244		3,977
APAC [Member]
Segment Reporting Information [Line Items]
Revenue	59,039	$ 45,662
Property and equipment - net	$ 4,047		$ 3,853

Segment and Significant Custo63

Segment and Significant Customer Information , Significant Customers (Details) - Customer Concentration Risk [Member]	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Exclusive Networks Group [Member] | Revenue [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	19.00%	17.00%
Exclusive Networks Group [Member] | Accounts Receivable [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	21.00%	23.00%
FineTec Computers [Member] | Accounts Receivable [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	13.00%

Accumulated Other Comprehensi64

Accumulated Other Comprehensive Income (Loss) (Changes in Accumulated Balances of Other Comprehensive Income)(Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016USD ($)
Accumulated Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance	$ (933)
Other comprehensive income (loss) before reclassifications	1,229
Amounts reclassified from accumulated other comprehensive income (loss)	(2)
Net current-period other comprehensive income (loss)	1,227
Ending balance	294
Tax Benefit (Provision) Related to Items of Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance, tax	504
Other comprehensive income before reclassifications, tax	(662)
Amounts reclassified from accumulated other comprehensive income, tax	1
Net current-period other comprehensive income, tax	(661)
Ending balance, tax	(157)
Unrealized Gains and Losses on Investments [Member]
Accumulated Other Comprehensive (Loss) Income [Roll Forward]
Beginning balance	(1,437)
Other comprehensive income (loss) before reclassifications	1,891
Amounts reclassified from accumulated other comprehensive income (loss)	(3)
Net current-period other comprehensive income (loss)	1,888
Ending balance	$ 451

Accumulated Other Comprehensi65

Accumulated Other Comprehensive Income (Loss) (Reclassification Out of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Line Items]
OTHER EXPENSE—net	$ (1,312)	$ (677)
Provision for income taxes	1,809	(83)
Net income (loss)	(3,429)	$ 1,560
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Line Items]
Provision for income taxes	1
Net income (loss)	(2)
Unrealized losses on investments [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income (Loss) [Line Items]
OTHER EXPENSE—net	$ (3)

Foreign Currency Derivatives (D

Foreign Currency Derivatives (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
CAD [Member] | Sell [Member]
Derivative [Line Items]
Notional amount of foreign exchange contracts	$ 8,540	$ 7,011
Minimum [Member]
Derivative [Line Items]
Derivative, term of contract	1 month
Maximum [Member]
Derivative [Line Items]
Derivative, term of contract	3 months

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
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Related Party Transaction [Line Items]
Expenses for legal services	$ 0.3	$ 1.9
Amounts due and payable to the law firm	0.4		$ 5.3
Contingency Fee Arrangement [Member]
Related Party Transaction [Line Items]
Expenses for legal services	$ 0.2	$ 0.5