Fortinet (FTNT) 10-Q 6 Nov 23 2023 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2023	Nov. 03, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
Document Transition Report	false
Entity File Number	001-34511
Entity Registrant Name	FORTINET, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	77-0560389
Entity Address, Address Line One	899 Kifer Road
Entity Address, City or Town	Sunnyvale
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94086
City Area Code	408
Local Phone Number	235-7700
Title of 12(b) Security	Common Stock, $0.001 Par Value
Trading Symbol	FTNT
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		767,909,603
Entity Central Index Key	0001262039
Amendment Flag	false
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
CURRENT ASSETS:
Cash and cash equivalents	$ 2,186.8	$ 1,682.9
Short-term investments	962.2	502.6
Marketable equity securities	19.8	25.5
Accounts receivable—net	1,013.8	1,261.7
Inventory	467.5	264.6
Prepaid expenses and other current assets	102.6	73.1
Total current assets	4,752.7	3,810.4
LONG-TERM INVESTMENTS	1.5	45.5
PROPERTY AND EQUIPMENT—NET	1,038	898.5
DEFERRED CONTRACT COSTS	569.9	518.2
DEFERRED TAX ASSETS	788.5	569.4
GOODWILL	125.4	128
OTHER INTANGIBLE ASSETS—NET	39.6	56
OTHER ASSETS	163.7	202
TOTAL ASSETS	7,479.3	6,228
CURRENT LIABILITIES:
Accounts payable	253.9	243.4
Accrued liabilities	317.2	248.7
Accrued payroll and compensation	210.5	219.4
Income taxes payable	220.1	17.6
Deferred revenue	2,647.3	2,349.3
Total current liabilities	3,649	3,078.4
DEFERRED REVENUE	2,638	2,291
INCOME TAX LIABILITIES	61.8	67.8
LONG-TERM DEBT	991.8	990.4
OTHER LIABILITIES	64.6	82
Total liabilities	7,405.2	6,509.6
COMMITMENTS AND CONTINGENCIES (Note 11)
STOCKHOLDERS’ EQUITY (DEFICIT):
Common stock, $0.001 par value—1,500.0 shares authorized; 776.3 and 781.5 shares issued and outstanding on September 30, 2023 and December 31, 2022, respectively	0.8	0.8
Additional paid-in capital	1,397	1,284.2
Accumulated other comprehensive loss	(24.3)	(20.2)
Accumulated deficit	(1,299.4)	(1,546.4)
Total stockholders’ equity (deficit)	74.1	(281.6)
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT)	$ 7,479.3	$ 6,228

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets Parenthetical - $ / shares	Sep. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Common Stock, par value (dollars per share)	$ 0.001	$ 0.001
Common Stock, shares authorized	1,500,000,000	1,500,000,000
Common Stock, shares issued	776,300,000	781,500,000
Common Stock, shares outstanding	776,300,000	781,500,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
REVENUE:
Total revenue	$ 1,334.6	$ 1,149.5	$ 3,889.7	$ 3,134.4
COST OF REVENUE:
Total cost of revenue	317.7	283	921.3	787.6
GROSS PROFIT:
Total gross profit	1,016.9	866.5	2,968.4	2,346.8
OPERATING EXPENSES:
Research and development	156.9	134.3	461.3	383.5
Sales and marketing	504.4	427.1	1,498.6	1,230.2
General and administrative	53.5	40.7	156.2	124.7
Gain on intellectual property matter	(1.1)	(1.1)	(3.4)	(3.4)
Total operating expenses	713.7	601	2,112.7	1,735
OPERATING INCOME	303.2	265.5	855.7	611.8
INTEREST INCOME	37	4.6	89.2	8.3
INTEREST EXPENSE	(5.4)	(4.5)	(15.6)	(13.5)
OTHER EXPENSE—NET	(7)	(0.9)	(11.2)	(19.3)
INCOME BEFORE INCOME TAXES AND LOSS FROM EQUITY METHOD INVESTMENT	327.8	264.7	918.1	587.3
PROVISION FOR (BENEFIT FROM) INCOME TAXES	(0.3)	27.3	48.6	21.6
LOSS FROM EQUITY METHOD INVESTMENT	(5.2)	(6.3)	(32.6)	(22.9)
NET INCOME INCLUDING NON-CONTROLLING INTERESTS	322.9	231.1	836.9	542.8
LESS: NET LOSS ATTRIBUTABLE TO NON-CONTROLLING INTERESTS, NET OF TAX	0	(0.5)	0	(0.7)
NET INCOME ATTRIBUTABLE TO FORTINET, INC.	$ 322.9	$ 231.6	$ 836.9	$ 543.5
Net income per share attributable to Fortinet, Inc. (Note 9):
Basic (in dollars per share)	$ 0.41	$ 0.29	$ 1.07	$ 0.68
Diluted (in dollars per share)	$ 0.41	$ 0.29	$ 1.05	$ 0.67
Weighted-average shares used to compute net income per share attributable to Fortinet, Inc.:
Basic (in shares)	781.2	786.2	783.1	795
Diluted (in shares)	791.2	798.6	793.5	809.8
Product
REVENUE:
Total revenue	$ 465.9	$ 468.7	$ 1,439.2	$ 1,240.4
COST OF REVENUE:
Total cost of revenue	198.3	185.2	566.4	501.4
GROSS PROFIT:
Total gross profit	267.6	283.5	872.8	739
Service
REVENUE:
Total revenue	868.7	680.8	2,450.5	1,894
COST OF REVENUE:
Total cost of revenue	119.4	97.8	354.9	286.2
GROSS PROFIT:
Total gross profit	$ 749.3	$ 583	$ 2,095.6	$ 1,607.8

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Statement of Comprehensive Income [Abstract]
Net income including non-controlling interests	$ 322.9	$ 231.1	$ 836.9	$ 542.8
Other comprehensive loss:
Change in foreign currency translation	(2.4)	(3.7)	(9.9)	(16.5)
Change in unrealized gains (losses) on investments	1.6	1	7.5	(10.7)
Less: tax provision (benefit) related to items of other comprehensive income or loss	0.4	0.3	1.7	(2.4)
Other comprehensive loss	(1.2)	(3)	(4.1)	(24.8)
Comprehensive income including non-controlling interests	321.7	228.1	832.8	518
Less: comprehensive loss attributable to non-controlling interests	0	(1.4)	0	(4.8)
Comprehensive income attributable to Fortinet, Inc.	$ 321.7	$ 229.5	$ 832.8	$ 522.8

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit	Non-Controlling Interests
Balance, shares at Dec. 31, 2021		810
Balance, beginning of period at Dec. 31, 2021	$ 798.4	$ 0.8	$ 1,253.6	$ (4.8)	$ (467.9)	$ 16.7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock in connection with equity incentive plans - net of tax withholding (in shares)		6.1
Issuance of common stock in connection with equity incentive plans - net of tax withholding	(110.6)		(110.6)
Repurchase and retirement of common stock (in shares)		(36)
Repurchase and retirement of common stock	(1,991.2)		(55.4)		(1,935.8)
Stock-based compensation expense	162.6		162.6
Net unrealized gain on investments - net of tax	(8.3)			(8.3)
Foreign currency translation adjustment	(16.5)			(12.4)		(4.1)
Net income including non-controlling interests	542.8				543.5	(0.7)
Balance, shares at Sep. 30, 2022		780.1
Balance, end of period at Sep. 30, 2022	(622.8)	$ 0.8	1,250.2	(25.5)	(1,860.2)	11.9
Balance, shares at Jun. 30, 2022		788.4
Balance, beginning of period at Jun. 30, 2022	(379.6)	$ 0.8	1,237.3	(23.4)	(1,607.6)	13.3
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock in connection with equity incentive plans - net of tax withholding (in shares)		1.9
Issuance of common stock in connection with equity incentive plans - net of tax withholding	(26)		(26)
Repurchase and retirement of common stock (in shares)		(10.2)
Repurchase and retirement of common stock	(500)		(15.8)		(484.2)
Stock-based compensation expense	54.7		54.7
Net unrealized gain on investments - net of tax	0.7			0.7
Foreign currency translation adjustment	(3.7)			(2.8)		(0.9)
Net income including non-controlling interests	231.1				231.6	(0.5)
Balance, shares at Sep. 30, 2022		780.1
Balance, end of period at Sep. 30, 2022	(622.8)	$ 0.8	1,250.2	(25.5)	(1,860.2)	11.9
Balance, shares at Dec. 31, 2022		781.5
Balance, beginning of period at Dec. 31, 2022	(281.6)	$ 0.8	1,284.2	(20.2)	(1,546.4)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock in connection with equity incentive plans - net of tax withholding (in shares)		5.2
Issuance of common stock in connection with equity incentive plans - net of tax withholding	(54.7)		(54.7)
Repurchase and retirement of common stock (in shares)		(10.4)
Repurchase and retirement of common stock	(605.2)		(15.3)		(589.9)
Excise tax on net stock repurchases	(2.8)		(2.8)
Stock-based compensation expense	185.6		185.6
Net unrealized gain on investments - net of tax	5.8			5.8
Foreign currency translation adjustment	(9.9)			(9.9)		0
Net income including non-controlling interests	836.9				836.9	0
Balance, shares at Sep. 30, 2023		776.3
Balance, end of period at Sep. 30, 2023	74.1	$ 0.8	1,397	(24.3)	(1,299.4)	0
Balance, shares at Jun. 30, 2023		785.6
Balance, beginning of period at Jun. 30, 2023	321.2	$ 0.8	1,375.9	(23.1)	(1,032.4)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock in connection with equity incentive plans - net of tax withholding (in shares)		1.1
Issuance of common stock in connection with equity incentive plans - net of tax withholding	(25.1)		(25.1)
Repurchase and retirement of common stock (in shares)		(10.4)
Repurchase and retirement of common stock	(605.2)		(15.3)		(589.9)
Excise tax on net stock repurchases	(2.8)		(2.8)
Stock-based compensation expense	64.3		64.3
Net unrealized gain on investments - net of tax	1.2			1.2
Foreign currency translation adjustment	(2.4)			(2.4)		0
Net income including non-controlling interests	322.9				322.9	0
Balance, shares at Sep. 30, 2023		776.3
Balance, end of period at Sep. 30, 2023	$ 74.1	$ 0.8	$ 1,397	$ (24.3)	$ (1,299.4)	$ 0

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income including non-controlling interests	$ 836.9	$ 542.8
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation	185.6	162.6
Amortization of deferred contract costs	195.9	163.8
Depreciation and amortization	83.2	77
Amortization of investment premiums (discounts)	(16.1)	3.6
Loss from equity method investment	32.6	22.9
Other	13.7	21.2
Changes in operating assets and liabilities, net of impact of business combinations:
Accounts receivable—net	243.4	(162.7)
Inventory	(231)	(59.7)
Prepaid expenses and other current assets	(29.3)	(7.6)
Deferred contract costs	(247.5)	(221)
Deferred tax assets	(221.7)	(172)
Other assets	13.5	(13.9)
Accounts payable	10.4	78.6
Accrued liabilities	56.9	33.7
Accrued payroll and compensation	(8)	(3.2)
Income taxes payable	196.8	(5.9)
Other liabilities	(17.7)	(0.5)
Deferred revenue	646.2	742.8
Net cash provided by operating activities	1,743.8	1,202.5
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of investments	(1,327.6)	(389.1)
Sales of investments	4	3
Maturities of investments	931.5	1,182.9
Purchases of property and equipment	(177.2)	(250.3)
Purchase of investment in privately held company	(8.5)	0
Other	0.1	0
Net cash provided by (used in) investing activities	(577.7)	546.5
CASH FLOWS FROM FINANCING ACTIVITIES:
Repurchase and retirement of common stock	(604.3)	(1,991.2)
Proceeds from issuance of common stock	36	21.7
Taxes paid related to net share settlement of equity awards	(90.8)	(132.1)
Other	(1.2)	(1.3)
Net cash used in financing activities	(660.3)	(2,102.9)
EFFECT OF EXCHANGE RATE CHANGES ON CASH AND CASH EQUIVALENTS	(1.9)	(1.2)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	503.9	(355.1)
CASH AND CASH EQUIVALENTS—Beginning of period	1,682.9	1,319.1
CASH AND CASH EQUIVALENTS—End of period	2,186.8	964
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Cash paid for income taxes—net	84.9	197.6
Operating lease liabilities arising from obtaining right-of-use assets	14.3	36.2
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Transfers of evaluation units from inventory to property and equipment	24.5	13.1
Liability for purchase of property and equipment	24.7	25.3
Liability incurred for repurchase of common stock	$ 0.9	$ 0

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2023
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 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 (the “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, 2022, contained in our Annual Report on Form 10-K filed with the SEC on February 24, 2023. In the opinion of management, all adjustments, which include normal recurring adjustments, considered necessary for a fair presentation, have been included. The results of operations for the three and nine months ended September 30, 2023 are not necessarily indicative of the results to be expected for the full year or for any future periods. The condensed consolidated balance sheet as of December 31, 2022 is derived from the audited consolidated financial statements for the year ended December 31, 2022. Amounts related to income taxes payable have been reclassified in prior periods to conform with current period presentation. The condensed consolidated financial statements include the accounts of Fortinet, Inc. and its subsidiaries. We consolidate all legal entities in which we have an absolute controlling financial interest. All intercompany balances and transactions have been eliminated in consolidation. The preparation of the condensed consolidated 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 and nine months ended September 30, 2023, as compared to the significant accounting policies described in the Form 10-K. Recently Adopted and Recently Issued Accounting Standards There were no recently adopted accounting standards which would have a material effect on our condensed consolidated financial statements and accompanying disclosures, and no recently issued accounting standards that are expected to have a material impact on our condensed consolidated financial statements and accompanying disclosures.

Revenue Recognition

Revenue Recognition	9 Months Ended
	Sep. 30, 2023
Revenue from Contract with Customer [Abstract]
REVENUE RECOGNITION	REVENUE RECOGNITION Disaggregation of Revenue The following table presents our revenue disaggregated by major product and service lines (in millions): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Product $ 465.9 $ 468.7 $ 1,439.2 $ 1,240.4 Service: Security subscription 494.6 369.8 1,373.6 1,023.1 Technical support and other 374.1 311.0 1,076.9 870.9 Total service revenue 868.7 680.8 2,450.5 1,894.0 Total revenue $ 1,334.6 $ 1,149.5 $ 3,889.7 $ 3,134.4 Deferred Revenue During the three and nine months ended September 30, 2023, we recognized $514.3 million and $1.80 billion in service revenue that was included in the deferred revenue balance as of December 31, 2022, respectively. During the three and nine months ended September 30, 2022, we recognized $401.9 million and $1.37 billion in service revenue that was included in the deferred revenue balance as of December 31, 2021, respectively. Transaction Price Allocated to the Remaining Performance Obligations As of September 30, 2023, the aggregate amount of the transaction price allocated to remaining performance obligations was $5.30 billion, which was substantially comprised of deferred security subscription, technical support services revenue and unbilled contract revenue from non-cancellable contracts that will be recognized in future periods. We expect to recognize approximately $2.66 billion as revenue over the next 12 months and the remainder thereafter. Accounts Receivable Trade accounts receivable are recorded at the invoiced amount, net of an allowance for expected credit losses. We measure expected credit losses of accounts receivable on a collective (pooled) basis, aggregating accounts receivable that are either current or no more than 60 days past due, and aggregating accounts receivable that are more than 60 days past due. We apply a credit-loss percentage to each of the pools that is based on our historical credit losses. We review whether each of our significant accounts receivable that is more than 60 days past due continues to exhibit similar risk characteristics with the other accounts receivable in the pool. If we determine that it does not, we evaluate it for expected credit losses on an individual basis. Expected credit losses are recorded as general and administrative expenses on our consolidated statements of income. The allowance for credit losses was $5.3 million and $3.6 million as of September 30, 2023 and December 31, 2022, respectively. Provisions, write-offs and recoveries were not material during the nine months ended September 30, 2023 and 2022. Deferred Contract Costs Amortization of deferred contract costs during the three months ended September 30, 2023 and 2022 were $68.0 million and $56.7 million, respectively. Amortization of deferred contract costs during the nine months ended September 30, 2023 and 2022 were $195.9 million and $163.8 million, respectively.

Financial Instruments and Fair

Financial Instruments and Fair Value	9 Months Ended
	Sep. 30, 2023
Financial Instruments and Fair Value [Abstract]
FINANCIAL INSTRUMENTS AND FAIR VALUE	FINANCIAL INSTRUMENTS AND FAIR VALUE Available-for-Sale Securities The following tables summarize our available-for-sale securities (in millions): September 30, 2023 Amortized Unrealized Unrealized Fair U.S. government and agency securities $ 423.4 $ 0.1 $ (0.5) $ 423.0 Commercial paper 400.0 — (0.3) 399.7 Certificates of deposit and term deposits 73.5 — — 73.5 Corporate debt securities 68.0 — (0.5) 67.5 Total available-for-sale securities $ 964.9 $ 0.1 $ (1.3) $ 963.7 December 31, 2022 Amortized Unrealized Unrealized Fair U.S. government and agency securities $ 198.0 $ — $ (4.4) $ 193.6 Commercial paper 26.5 — (0.1) 26.4 Certificates of deposit and term deposits 34.2 — — 34.2 Corporate debt securities 293.0 — (4.1) 288.9 Municipal bonds 5.1 — (0.1) 5.0 Total available-for-sale securities $ 556.8 $ — $ (8.7) $ 548.1 The following tables show the gross unrealized losses and the related fair values of our available-for-sale securities that have been in a continuous unrealized loss position (in millions): September 30, 2023 Less Than 12 Months 12 Months or Greater Total Fair Unrealized Fair Unrealized Fair Unrealized U.S. government and agency securities $ 159.1 $ (0.1) $ 32.6 $ (0.4) $ 191.7 $ (0.5) Commercial paper 376.6 (0.3) — — 376.6 (0.3) Corporate debt securities 15.3 — 46.4 (0.5) 61.7 (0.5) Total available-for-sale securities $ 551.0 $ (0.4) $ 79.0 $ (0.9) $ 630.0 $ (1.3) December 31, 2022 Less Than 12 Months 12 Months or Greater Total Fair Unrealized Fair Unrealized Fair Unrealized U.S. government and agency securities $ 3.9 $ (0.1) $ 189.8 $ (4.3) $ 193.7 $ (4.4) Commercial paper 26.4 (0.1) — — 26.4 (0.1) Corporate debt securities 90.5 (0.8) 190.0 (3.3) 280.5 (4.1) Municipal bonds 5.0 (0.1) — — 5.0 (0.1) Total available-for-sale securities $ 125.8 $ (1.1) $ 379.8 $ (7.6) $ 505.6 $ (8.7) The contractual maturities of our investments were (in millions): September 30, December 31, Due within one year $ 962.2 $ 502.6 Due within one to three years 1.5 45.5 Total $ 963.7 $ 548.1 Available-for-sale securities are reported at fair value, with unrealized gains and losses and the related tax impact included as a separate component of equity (deficit) and in comprehensive income. We do not intend to sell any of the securities in an unrealized loss position and it is not more likely than not that we would be required to sell these securities before recovery of their amortized cost basis, which may be at maturity. Realized gains and losses on available-for-sale securities were insignificant in the periods presented. Marketable Equity Securities Our marketable equity securities were $19.8 million and $25.5 million as of September 30, 2023 and December 31, 2022. The changes in fair value of our marketable equity securities are recorded in other expense—net on the condensed consolidated statements of income. We recognized a $2.3 million and $5.7 million loss during the three and nine months ended September 30, 2023, respectively. We recognized a $2.6 million gain and a $11.7 million loss during the three and nine months ended September 30, 2022, respectively. Fair Value of Financial Instruments 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: 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, certain U.S. government and agency securities and marketable equity 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. Assets Measured at Fair Value on a Recurring Basis The following tables present the fair value of our financial assets measured at fair value on a recurring basis (in millions): September 30, 2023 December 31, 2022 Aggregate Quoted Significant Significant Aggregate Quoted Significant Significant (Level 1) (Level 2) (Level 3) (Level 1) (Level 2) (Level 3) Assets: U.S. government and agency securities $ 474.1 $ 402.4 $ 71.7 $ — $ 268.6 $ 259.3 $ 9.3 $ — Commercial paper 439.5 — 439.5 — 115.8 — 115.8 — Certificates of deposit and term deposits 93.5 — 93.5 — 50.4 — 50.4 — Corporate debt securities 67.5 — 67.5 — 288.9 — 288.9 — Money market funds 325.0 325.0 — — 593.9 593.9 — — Municipal bonds — — — — 5.0 — 5.0 — Marketable equity securities 19.8 19.8 — — 25.5 25.5 — — Total $ 1,419.4 $ 747.2 $ 672.2 $ — $ 1,348.1 $ 878.7 $ 469.4 $ — Reported as: Cash equivalents $ 435.9 $ 774.5 Marketable equity securities 19.8 25.5 Short-term investments 962.2 502.6 Long-term investments 1.5 45.5 Total $ 1,419.4 $ 1,348.1 There were no transfers between Level 1 and Level 2 of the fair value hierarchy during the nine months ended September 30, 2023 and year ended December 31, 2022.

Inventory

Inventory	9 Months Ended
	Sep. 30, 2023
Inventory Disclosure [Abstract]
INVENTORY	INVENTORY Inventory consisted of (in millions): September 30, December 31, Raw materials $ 77.5 $ 46.3 Work in process 8.0 12.0 Finished goods 382.0 206.3 Inventory $ 467.5 $ 264.6

Property and Equipment_Net

Property and Equipment—Net	9 Months Ended
	Sep. 30, 2023
Property, Plant and Equipment [Abstract]
PROPERTY AND EQUIPMENT—Net	PROPERTY AND EQUIPMENT—Net Property and equipment—net consisted of (in millions): September 30, December 31, Land $ 351.7 $ 310.0 Buildings and improvements 591.7 490.3 Computer equipment and software 252.3 222.7 Leasehold improvements 60.6 53.5 Evaluation units 27.5 19.2 Furniture and fixtures 30.5 31.3 Construction-in-progress 55.8 51.7 Total property and equipment 1,370.1 1,178.7 Less: accumulated depreciation (332.1) (280.2) Property and equipment—net $ 1,038.0 $ 898.5 During the three months ended June 30, 2023, we purchased certain real estate in Spain and the United States for a total purchase price of $51.9 million. The purchases were accounted for under the asset acquisition method. The cost of the assets acquired was allocated to land and buildings and improvements based on their relative fair values. The total purchase price was allocated as $6.5 million to land and $45.4 million to buildings and improvements. During the three months ended September 30, 2023, we purchased certain real estate in Australia for a total purchase price of $41.3 million. The purchase was accounted for under the asset acquisition method. The cost of the assets acquired was allocated to land and construction-in-progress based on their relative fair values. The total purchase price was allocated as $21.5 million to land and $19.8 million to construction-in-progress. Depreciation expense was $23.9 million and $21.2 million during the three months ended September 30, 2023 and 2022, respectively. Depreciation expense was $69.6 million and $59.4 million during the nine months ended September 30, 2023 and 2022, respectively.

Investments in Privately Held C

Investments in Privately Held Companies	9 Months Ended
	Sep. 30, 2023
Investments, All Other Investments [Abstract]
INVESTMENTS IN PRIVATELY HELD COMPANIES	INVESTMENTS IN PRIVATELY HELD COMPANIES Linksys Holdings, Inc. During 2021, we invested $160 million in cash for shares of the Series A Preferred Stock of privately held Linksys Holdings, Inc. (“Linksys”), representing a 50.8% ownership interest in the outstanding common stock (on an as-converted basis). Linksys provides router connectivity solutions to the consumer and small business markets. We have concluded that our investment in Linksys is an in-substance common stock investment and that we do not hold an absolute controlling financial interest in Linksys, but that we have the ability to exercise significant influence over the operating and financial policies of Linksys. Determining that we have significant influence but not control over the operating and financial policies of Linksys required significant judgement of many factors, including but not limited to the ownership interest in Linksys, board representation, participation in policy-making processes and participation rights in certain significant financial and operating decisions of Linksys in the ordinary course of business. Therefore, we determined to account for this investment using the equity method of accounting. We record our share of Linksys’ financial results on a three-month lag basis. We determined that there was a basis difference between the cost of our investment in Linksys and the amount of underlying equity in net assets of Linksys. Our share of loss of Linksys’ financial results, as well as our share of the amortization of the basis differences, totaled $5.2 million and $6.3 million for the three months ended September 30, 2023 and 2022, respectively, and has been recorded in loss from equity method investment on the condensed consolidated statements of income. Our share of loss of Linksys’ financial results, as well as our share of the amortization of the basis differences, totaled $32.6 million and $22.9 million for the nine months ended September 30, 2023 and 2022, respectively, and has been recorded in loss from equity method investment on the condensed consolidated statements of income. The carrying amount of our Linksys investment was $51.6 million and $84.3 million as of September 30, 2023 and December 31, 2022, respectively, and the investment was included in other assets on our condensed consolidated balance sheets. In the fourth quarter of 2022, we recorded a non-cash charge of $22.2 million related to other-than-temporary impairment (“OTTI”) recognized on our equity method investment in Linksys and our proportionate share of Linksys' financial results included a $17.5 million charge in connection with a valuation allowance established on deferred tax assets at Linksys. Due to the presence of impairment indicators, such as a series of operating losses, we evaluated our equity method investment for an OTTI during the three months ended September 30, 2023. We considered various factors in determining whether an OTTI has occurred, including the limited operating history available, our ability and intent to hold the investment until its fair value recovers, the implied revenue valuation multiples compared to guideline public companies, Linksys’ ability to achieve milestones and any notable operational and strategic changes. After the evaluation, we determined that an additional OTTI has not occurred as of September 30, 2023. However, we may be required to recognize an impairment loss in future reporting periods if and when our evaluation of the aforementioned factors indicates that the investment in Linksys is determined to be other than temporarily impaired. Such determination will be based on the prevailing facts and circumstances at that time, including the results and disclosures of Linksys. Other Investment On August 1, 2023, we invested $8.5 million in cash for a 19.5% ownership interest in the outstanding common stock of a privately held company that provides rugged ethernet switches, 4G/5G industrial routers and media converters for critical infrastructure customers. We accounted for our investment as an equity method investment since we have the ability to exercise significant influence, but not control, over the operating and financial policies of the privately-held company. We will record our proportionate share of the company’s financial results on a three-month lag basis and will present it in loss from equity method investments—net on the condensed consolidated statements of income.

Business Combinations

Business Combinations	9 Months Ended
	Sep. 30, 2023
Business Combination and Asset Acquisition [Abstract]
BUSINESS COMBINATIONS	BUSINESS COMBINATIONS Alaxala Networks Corporation On August 31, 2021, we closed an acquisition of 75% of equity interests as controlling interests

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets - Net	9 Months Ended
	Sep. 30, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND OTHER INTANGIBLE ASSETS - Net	GOODWILL AND OTHER INTANGIBLE ASSETS—Net Goodwill The following table presents the changes in the carrying amount of goodwill (in millions): Amount Balance—December 31, 2022 $ 128.0 Foreign currency translation adjustments (2.6) Balance—September 30, 2023 $ 125.4 There were no impairments to goodwill during the nine months ended September 30, 2023 or during prior periods. Other Intangible Assets—Net The following tables present other intangible assets—net (in millions, except years): September 30, 2023 Weighted-Average Useful Life (in Years) Gross Accumulated Amortization Net Other intangible assets—net: Finite-lived intangible assets: Developed technologies 4.3 $ 82.3 $ 59.7 $ 22.6 Customer relationships 7.0 30.0 16.7 13.3 Trade name 10.0 4.7 1.0 3.7 Backlog 1.0 3.7 3.7 — Total other intangible assets—net $ 120.7 $ 81.1 $ 39.6 December 31, 2022 Weighted-Average Useful Life (in Years) Gross Accumulated Amortization Net Other intangible assets—net: Finite-lived intangible assets: Developed technologies 4.1 $ 85.1 $ 50.3 $ 34.8 Customer relationships 7.1 31.0 14.4 16.6 Trade name 10.0 5.3 0.7 4.6 Backlog 1.0 4.2 4.2 — Total other intangible assets—net $ 125.6 $ 69.6 $ 56.0 Amortization expense was $4.4 million and $5.2 million during the three months ended September 30, 2023 and 2022, respectively. Amortization expense was $13.6 million and $17.6 million during the nine months ended September 30, 2023 and 2022, respectively. The following table summarizes estimated future amortization expense of finite-lived intangible assets—net (in millions): Amount Years: 2023 (the remainder of 2023) $ 4.0 2024 12.7 2025 8.2 2026 4.1 2027 3.8 Thereafter 6.8 Total $ 39.6

Net Income Per Share

Net Income Per Share	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
NET INCOME PER SHARE	NET INCOME PER SHAREBasic net income per share is computed by dividing net income attributable to Fortinet, Inc., by the weighted-average number of shares of common stock outstanding during the period. Diluted net income per share is computed by dividing net income attributable to Fortinet, Inc. by the weighted-average number of shares of common stock outstanding during the period, plus the dilutive effects of restricted stock units (“RSUs”), stock options and performance stock units (“PSUs”). Dilutive shares of common stock are determined by applying the treasury stock method. A reconciliation of the numerator and denominator used in the calculation of basic and diluted net income per share attributable to Fortinet, Inc. is (in millions, except per share amounts): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Numerator: Net income including non-controlling interests $ 322.9 $ 231.1 $ 836.9 $ 542.8 Net loss attributable to non-controlling interests — (0.5) — (0.7) Net income attributable to Fortinet, Inc. $ 322.9 $ 231.6 $ 836.9 $ 543.5 Denominator: Basic shares: Weighted-average common stock outstanding-basic 781.2 786.2 783.1 795.0 Diluted shares: Weighted-average common stock outstanding-basic 781.2 786.2 783.1 795.0 Effect of potentially dilutive securities: RSUs 3.5 4.9 3.8 6.6 Stock options 6.2 7.5 6.4 8.2 PSUs 0.3 — 0.2 — Weighted-average shares used to compute diluted net income per share attributable to Fortinet, Inc. 791.2 798.6 793.5 809.8 Net income per share attributable to Fortinet, Inc.: Basic $ 0.41 $ 0.29 $ 1.07 $ 0.68 Diluted $ 0.41 $ 0.29 $ 1.05 $ 0.67 The following weighted-average shares of common stock were excluded from the computation of diluted net income per share attributable to Fortinet, Inc. for the periods presented, as their effect would have been antidilutive (in millions): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, RSUs — 2.5 0.6 1.1 Stock options 3.0 1.6 2.8 1.4 Total 3.0 4.1 3.4 2.5

Debt

Debt	9 Months Ended
	Sep. 30, 2023
Debt Disclosure [Abstract]
DEBT	DEBT 2026 and 2031 Senior Notes On March 5, 2021, we issued $1.0 billion aggregate principal amount of senior notes (collectively, the “Senior Notes”), consisting of $500.0 million aggregate principal amount of 1.0% notes due March 15, 2026 (the “2026 Senior Notes”) and $500.0 million aggregate principal amount of 2.2% notes due March 15, 2031 (the “2031 Senior Notes”), in an underwritten registered public offering. The Senior Notes are senior unsecured obligations and rank equally with each other in right of payment and with our other outstanding obligations. We may redeem the Senior Notes at any time in whole or in part for cash, at specified redemption prices that include accrued and unpaid interest, if any, and a make-whole premium. However, no make-whole premium will be paid for redemptions of the 2026 Senior Notes on or after February 15, 2026, or the 2031 Senior Notes on or after December 15, 2030. Interest on the Senior Notes is payable on March 15 and September 15 of each year, beginning on September 15, 2021. As of September 30, 2023 and December 31, 2022, the Senior Notes were recorded as long-term debt, net of discount and issuance costs, which are amortized to interest expense over the respective contractual terms of these notes using the effective interest method. The total outstanding debt is summarized below (in millions, except percentages): Maturity Coupon Rate Effective Interest Rate September 30, December 31, Debt 2026 Senior Notes March 2026 1.0% 1.3% $ 500.0 $ 500.0 2031 Senior Notes March 2031 2.2% 2.3% 500.0 500.0 Total debt 1,000.0 1,000.0 Less: Unamortized discount and debt issuance costs 8.2 9.6 Total long-term debt $ 991.8 $ 990.4 As of September 30, 2023 and December 31, 2022, we accrued interest payable of $0.7 million and $4.7 million, respectively, and there are no financial covenants with which we must comply. During the three months ended September 30, 2023 and 2022, we recorded $4.5 million and $4.4 million of total interest expense in relation to these Senior Notes in each quarter, respectively. During the nine months ended September 30, 2023 and 2022, we recorded $13.5 million and $13.4 million of total interest expense in relation to the Senior Notes in each period, respectively. No interest costs were capitalized for the nine months ended September 30, 2023 and 2022, as the costs that qualified for capitalization were not material. The total estimated fair value of the outstanding Senior Notes was approximately $834.8 million, including accrued and unpaid interest, as of September 30, 2023. The fair value was determined based on observable market prices of identical instruments in less active markets. The estimated fair values are based on Level 2 inputs.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES The following table summarizes our inventory purchase commitments as of September 30, 2023 (in millions): Total 2023 Thereafter Inventory purchase commitments $ 820.6 $ 608.5 $ 212.1 Inventory Purchase Commitments —Our independent contract manufacturers and certain component suppliers procure components and build our products based on our forecasts, the availability of various components and their capacity. 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 lead times, changes in supplier delivery commitments and other supply chain matters and market conditions. In order to manage manufacturing lead times, plan for adequate component supply and incentivize suppliers to deliver, we may issue purchase orders to some of our independent contract manufacturers, which are non-cancelable. As of September 30, 2023, we had $820.6 million of open purchase orders with our independent contract manufacturers that consist of non-cancelable commitments. In certain instances, these agreements allow us the option to reschedule and adjust our requirements based on our business needs prior to firm orders being placed. We recorded a liability for non-cancelable inventory purchase commitments for quantities in excess of our future estimated demand forecasts, consistent with the valuation of our excess and obsolete inventory. As of September 30, 2023, the liability for these inventory purchase commitments was $64.6 million and was included in accrued liabilities. As of December 31, 2022, the liability for these purchase commitments was not material. The expense related to such accrued liability for inventory purchase commitments was $36.9 million and $59.3 million during the three and nine months ended September 30, 2023, respectively, and was recorded in product cost of revenue on the condensed consolidated statements of income. 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. A significant portion of our reported purchase commitments consist of non-cancelable commitments. In certain instances, contractual commitments allow us the option to cancel, reschedule and adjust our requirements based on our business needs prior to firm orders being placed. As of September 30, 2023, we had $76.8 million in other contractual commitments having a remaining term in excess of one year that are non-cancelable. As of September 30, 2023, we had $89.5 million in contractual commitments related to payments for operating leases. 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 certain of these matters is currently not determinable and not predictable, we currently are unaware of any existing claims or proceedings that we believe 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, costs and substantial settlement charges, and possibly subject us to damages and other penalties. In addition, the resolution of any intellectual property (“IP”) 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. Litigation is unpredictable and the actual liability in any such matters may be materially different from our current estimates, which could result in the need to adjust any accrued liability and record additional expenses. We accrue for contingencies when we believe that a loss is probable and that we can reasonably estimate the amount of any such loss. These accruals are generally based on a range of possible outcomes that require significant management judgement. If no amount within a range is a better estimate than any other, we accrue the minimum amount. Litigation loss contingency accruals associated with outstanding cases were not material as of September 30, 2023, and December 31, 2022. On March 21, 2019, we were sued by Alorica Inc. (“Alorica”) in Santa Clara County Superior Court in California. Alorica has alleged breach of warranty and misrepresentation claims, which we deny. Fact discovery closed during the quarter ended June 30, 2023. Although we believe that the ultimate outcome of this matter will not materially impact our financial position, results of operations or cash flows, legal proceedings are subject to inherent uncertainties, and an unfavorable ruling could occur, which may result in a material adverse impact on our business, financial position, results of operations and cash flows. No loss accrual had been recorded as of September 30, 2023 or December 31, 2022 related to this litigation. Indemnification and Other Matters —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 IP 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 IP infringement 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. Although from time to time there are indemnification claims asserted against us and currently there are pending indemnification claims, to date there have been no material awards under such indemnification provisions. Similar to other security companies and companies in other industries, we have experienced and may experience in the future, cybersecurity threats, malicious activity directed against our information technology infrastructure or unauthorized attempts to gain access to our and our customers’ sensitive information and systems. We currently are unaware of any existing claims or proceedings related to these types of matters, including any that we believe are likely to have a material adverse effect on our financial position.

Equity Plans and Share Repurcha

Equity Plans and Share Repurchase Program	9 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
EQUITY PLANS AND SHARE REPURCHASE PROGRAM	EQUITY PLANS AND SHARE REPURCHASE PROGRAM Stock-Based Compensation Plans We maintain the Amended and Restated Fortinet, Inc. 2009 Equity Incentive Plan (the “Amended Plan”) pursuant to which we have granted RSUs, stock options and PSUs. As of September 30, 2023, there were a total of 53.3 million shares of common stock available for grant under the Amended Plan. Restricted Stock Units The following table summarizes the activity and related information for RSUs for the periods presented below (in millions, except per share amounts): Restricted Stock Units Outstanding Number of Shares Weighted-Average Grant Date Fair Value per Share Balance—December 31, 2022 10.5 $ 40.94 Granted 4.5 60.85 Forfeited (0.6) 48.33 Vested (4.3) 34.88 Balance—September 30, 2023 10.1 $ 51.91 Stock compensation expense is recognized on a straight-line basis over the vesting period of each RSU. As of September 30, 2023, total compensation expense related to unvested RSUs granted to employees and non-employees under the Amended Plan, but not yet recognized, was $460.9 million, with a weighted-average remaining vesting period of 2.7 years. RSUs settle into shares of common stock upon vesting. Upon the vesting of the RSUs, we net-settle the RSUs and withhold a portion of the shares to satisfy employee withholding tax requirements. The payment of the withheld taxes to the tax 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 millions): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Shares withheld for taxes 0.4 0.5 1.5 2.2 Amount withheld for taxes $ 31.0 $ 32.0 $ 90.7 $ 132.1 Employee Stock Options The following table summarizes the weighted-average assumptions relating to our employee stock options: Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Expected term in years 4.4 4.4 4.4 4.4 Volatility 42.8 % 42.5 % 42.0 % 41.2 % Risk-free interest rate 4.5 % 3.1 % 4.2 % 2.0 % Dividend rate — % — % — % — % The following table summarizes the stock option activity and related information for the periods presented below (in millions, except exercise prices and contractual life): Options Outstanding Number Weighted- Weighted- Aggregate Balance—December 31, 2022 13.2 $ 24.37 3.5 $ 344.8 Granted 1.3 60.59 Forfeited (0.1) 47.86 Exercised (2.4) 14.89 Balance—September 30, 2023 12.0 $ 29.95 Options vested and expected to vest—September 30, 2023 12.0 $ 29.95 3.4 $ 350.2 Options exercisable—September 30, 2023 8.4 $ 21.24 2.6 $ 317.9 The aggregate intrinsic value represents the difference between the exercise price of stock options and the quoted market price of our common stock for all in-the-money stock options. Stock compensation expense is recognized on a straight-line basis over the vesting period of each stock option. As of September 30, 2023, total compensation expense related to unvested stock options granted to employees but not yet recognized was $61.4 million, with a weighted-average remaining vesting period of 2.6 years. Additional information related to our stock options is summarized below (in millions, except per share amounts): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Weighted-average fair value per share granted $ 23.67 $ 20.22 $ 24.37 $ 22.09 Intrinsic value of options exercised $ 13.9 $ 29.7 $ 110.9 $ 73.3 Fair value of options vested $ 6.1 $ 4.8 $ 23.5 $ 19.8 Market/Performance-Based PSUs We granted market/performance-based PSUs under the Amended Plan to certain of our executives. Based on the achievement of the market/performance-based vesting conditions during the performance period, the final settlement of the PSUs will range between 0% and 200% of the target shares underlying the PSUs based on the percentile ranking of our total stockholder return over one two three one two three The following table summarizes the weighted-average assumptions relating to our PSUs for the three months ended March 31, 2023: Three Months Ended March 31, Expected term in years 2.7 Volatility 47.5 % Risk-free interest rate 4.6 % Dividend rate — % We granted approximately 0.3 million shares of PSU awards with a grant date fair value of $90.96 per share to certain of our executives during the first quarter of 2023. The grant date fair value of these awards was determined using a Monte Carlo simulation pricing model. None of these PSU awards were vested or forfeited during the nine months ended September 30, 2023. As of September 30, 2023, total compensation expense related to unvested PSUs that were granted to certain of our executives, but not yet recognized, was $19.4 million. This expense is expected to be amortized on a graded vesting method over a weighted-average vesting period of 2.4 years. Stock-Based Compensation Expense Stock-based compensation expense, including stock-based compensation expense related to awards classified as liabilities, is included in costs and expenses (in millions): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Cost of product revenue $ 0.4 $ 0.5 $ 1.3 $ 1.3 Cost of service revenue 6.1 4.8 17.2 14.0 Research and development 20.0 16.7 57.0 47.9 Sales and marketing 28.5 25.9 84.1 79.0 General and administrative 9.9 7.4 28.0 22.3 Total stock-based compensation expense $ 64.9 $ 55.3 $ 187.6 $ 164.5 The following table summarizes stock-based compensation expense, including stock-based compensation expense related to awards classified as liabilities, by award type (in millions): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, RSUs $ 54.2 $ 48.9 $ 158.4 $ 146.2 Stock options 7.5 6.4 21.5 18.3 PSUs 3.2 — 7.7 — Total stock-based compensation expense $ 64.9 $ 55.3 $ 187.6 $ 164.5 Total income tax benefit associated with stock-based compensation that is recognized in the condensed consolidated statements of income is as follows (in millions): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Income tax benefit associated with stock-based compensation $ 14.3 $ 12.2 $ 41.4 $ 36.2 Share Repurchase Program In February 2023, our board of directors approved an extension of the Repurchase Program originally approved by our board of directors in January 2016 to February 29, 2024. In April 2023 and July 2023, our board of directors approved $1.0 billion and $500.0 million increases in the authorized amount under the Repurchase Program, respectively, bringing the aggregate amount authorized to be repurchased to $6.75 billion of our outstanding common stock through February 29, 2024. Share repurchases may be made by us from time to time in privately negotiated transactions or in open-market transactions. The Repurchase 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.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2023
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES Our effective tax rate was 0% for the three months ended September 30, 2023, compared to an effective tax rate of 10% for the same period last year. Our effective tax rate was 5% for the nine months ended September 30, 2023, compared to an effective tax rate of 4% for the same period last year. The tax rates for the three months ended September 30, 2023 and 2022 were composed of U.S. federal and state taxes, withholding taxes and foreign taxes that amounted to $50.2 million and $75.5 million , respectively. The tax rate for the three months ended September 30, 2023 was impacted by a tax benefit of $41.9 million from the FDII deduction, and excess tax benefits from stock-based compensation expense of $8.6 million . The tax rate for the three months ended September 30, 2022 was impacted by a tax benefit of $28.9 million from the FDII deduction, and excess tax benefits from stock-based compensation expense of $19.3 million. The tax rates for the nine months ended September 30, 2023 and 2022 were composed of U.S. federal and state taxes, withholding taxes and foreign taxes that amounted to $220.9 million and $169.2 million, respectively. The tax rate for the nine months ended September 30, 2023 was impacted by a tax benefit of $105.9 million from the FDII deduction, excess tax benefits from stock-based compensation expense of $48.3 million, and the release of reserves of $18.1 million on uncertain tax positions and the accrued interest thereon due to the expiration of statutes of limitations. The tax rate for the nine months ended September 30, 2022 was impacted by a tax benefit of $62.6 million from the FDII deduction, excess tax benefits from stock-based compensation expense of $68.7 million, and the release of reserves of $16.3 million on uncertain tax positions and the accrued interest thereon due to the expiration of statutes of limitations. As of September 30, 2023 and December 31, 2022, unrecognized tax benefits were $65.8 million and $67.4 million , respectively. If recognized, $55.9 million of the unrecognized tax benefits as of September 30, 2023 would favorably affect our effective tax rate. It is our policy to include accrued interest and penalties related to unrecognized tax benefits in income tax expense. As of September 30, 2023 and December 31, 2022, accrued interest and penalties were $5.9 million and $9.3 million, respectively. It is reasonably possible that our gross unrecognized tax benefits will decrease by up to $1.8 million in the next 12 months, due to the lapse of statutes of limitation in various jurisdictions. This decrease, if recognized, would favorably impact our effective tax rate, and would be recognized as an additional tax benefit. We file income tax returns in the U.S. federal jurisdiction and in various U.S. state and foreign jurisdictions. Generally, we are no longer subject to examination by U.S federal income tax authorities for tax years prior to 2015. We are no longer subject to U.S. state and foreign income tax examinations by tax authorities for tax years prior to 2010. We currently have ongoing tax audits in the United Kingdom, Canada, Germany and several other foreign jurisdictions. The focus of these audits is the inter-company profit allocation. Effective January 1, 2022, research and development expenses are required to be capitalized and amortized for U.S. tax purposes, which delays the deductibility of these expenses, and increases our current provision. On January 4, 2022, the U.S. Treasury published another tranche of final regulations regarding the foreign tax credit. These final regulations impose new requirements that a foreign tax must meet in order to be creditable against U.S. income taxes, and generally apply to tax years beginning on or after December 28, 2021. On July 26, 2022, the U.S. Treasury released corrections to the final regulations. On July 21, 2023, the IRS released a notice that suspended the application of significant portions of the final regulations regarding the foreign tax credit for tax years 2022 and 2023. The notice released in July 2023 favorably impacted our ability to claim foreign tax credits in the United States for certain taxes imposed by certain foreign jurisdictions. As a result, our tax provision decreased by $39.8 million for the nine months ended September 30, 2023. On August 16, 2022, the United States enacted the Inflation Reduction Act of 2022 that provides for certain changes to the U.S. corporate income tax system, including a 15% minimum tax based on financial statement income for companies with three-year average annual adjusted financial statement income exceeding $1 billion, and a 1% excise tax on net repurchases of stock after December 31, 2022, if any. The applicable tax law changes have had no impact to our tax provision for the nine months ended September 30, 2023. We will continue to monitor the impact, if any, of these tax law changes on future periods.

Defined Contribution Plans

Defined Contribution Plans	9 Months Ended
	Sep. 30, 2023
Retirement Benefits [Abstract]
DEFINED CONTRIBUTION PLANS	DEFINED CONTRIBUTION PLANS Our tax-deferred savings plan under our 401(k) Plan permits participating U.S. employees to contribute a portion of their pre-tax or after-tax earnings. In Canada, we have a Group Registered Retirement Savings Plan Program (the “RRSP”), which permits participants to make pre-tax 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 our 401(k) Plan and the RRSP for the three months ended September 30, 2023 and 2022 were $3.8 million and $3.2 million, respectively. Our matching contributions to our 401(k) Plan and the RRSP for the nine months ended September 30, 2023 and

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2023
Segment Reporting [Abstract]
SEGMENT INFORMATION	SEGMENT 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 our customers. The following tables set forth revenue and property and equipment—net by geographic region (in millions): Three Months Ended Nine Months Ended Revenue September 30, September 30, September 30, September 30, Americas: United States $ 400.8 $ 344.1 $ 1,189.6 $ 942.8 Other Americas 144.8 123.5 416.5 321.0 Total Americas 545.6 467.6 1,606.1 1,263.8 Europe, Middle East and Africa (“EMEA”) 512.2 443.9 1,497.3 1,181.7 Asia Pacific (“APAC”) 276.8 238.0 786.3 688.9 Total revenue $ 1,334.6 $ 1,149.5 $ 3,889.7 $ 3,134.4 Property and Equipment — net September 30, December 31, Americas: United States $ 696.7 $ 638.1 Canada 209.8 204.4 Latin America 1.2 1.1 Total Americas 907.7 843.6 EMEA 68.7 35.9 APAC 61.6 19.0 Total property and equipment—net $ 1,038.0 $ 898.5 The following distributors accounted for 10% or more of our revenue: Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Distributor A 28 % 29 % 28 % 29 % Distributor B 15 % 13 % 15 % 13 % Distributor C 13 % 13 % 14 % 13 % The following distributors accounted for 10% or more of net accounts receivable: September 30, December 31, Distributor A 26 % 32 % Distributor B 13 % 12 % Distributor C 13 % 13 %

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2023
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENT Share Repurchase Program Subsequent to September 30, 2023 through the filing of this Quarterly Report on Form 10-Q, we repurchased 11.2 million shares of our common stock at an average price of $54.87 per share for an aggregate purchase price of $613.5 million under the Repurchase Program, which excludes a $5.7 million accrual related to the 1% excise tax imposed by the Inflation Reduction Act of 2022.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Pay vs Performance Disclosure
Net income	$ 322.9	$ 231.6	$ 836.9	$ 543.5

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended	9 Months Ended
	Sep. 30, 2023 shares	Sep. 30, 2023 shares
Trading Arrangements, by Individual
Material Terms of Trading Arrangement		Rule 10b5-1 Trading Plans On August 16, 2023, the Xie Foundation, a non-profit entity for which Michael Xie and Ken Xie, both of which are our officers and directors, serve as co-presidents and directors, and Michael Xie entered into a pre-arranged written stock sale plan in accordance with Rule 10b5-1 (the “August Xie Plan”) under the Exchange Act for the sale of shares of our common stock. The August Xie Plan was entered into during an open trading window in accordance with our insider trading policy and is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. The August Xie Plan provides for (i) the potential sale by Michael Xie of up to (a) 100,000 shares of our common stock, including upon the vesting and settlement of RSUs and PSUs for shares of our common stock, and (b) the net shares (which are not yet determinable) after shares are withheld to satisfy tax obligations upon such vesting and settlement, in each case, at the market price, and (ii) the potential gifting of up to 50,000 shares of our common stock by the Xie Foundation, all between November 15, 2023 and November 29, 2024. On September 8, 2023, Michael Xie and the Xie Foundation amended the August Xie Plan in order to provide for sales of our common stock thereunder by Ken Xie, in addition to the sales provided for by the August Xie Plan (as so amended, the “September Xie Plan”). The September Xie Plan was entered into during an open trading window in accordance with our insider trading policy and is intended to satisfy the affirmative defense of Rule 10b5-1(c) under the Exchange Act. The September Xie Plan provides for (i) the potential sale by Michael Xie of up to (a) 100,000 shares of our common stock, including upon the vesting and settlement of RSUs and PSUs for shares of our common stock, and (b) the net shares (which are not yet determinable) after shares are withheld to satisfy tax obligations upon such vesting and settlement, in each case, at the market price, (ii) the potential sale by Ken Xie of up to (a) 150,000 shares of our common stock, including upon the exercise of vested stock options for shares of our common stock, and (b) the net shares (which are not yet determinable) after shares are sold to pay the exercise price and tax withholding obligations associated with such exercises, in each case, at the market price and (iii) the potential gifting of up to 50,000 shares of our common stock by the Xie Foundation, all between December 8, 2023 and February 14, 2025. Each of the August Xie Plan and the September Xie Plan (together, the “10b5-1 Plans”) includes a representation from Michael Xie, Ken Xie and the Xie Foundation (as applicable) to the broker administering the plan that none of them were in possession of any material nonpublic information regarding us or the securities subject to the 10b5-1 Plans at the time the 10b5-1 Plans were entered into. A similar representation was made to us in connection with the adoption of the 10b5-1 Plans under our insider trading policy. Those representations for each 10b5-1 Plan were made as of the respective date of adoption of the 10b5-1 Plan, and speak only as of that date. In making those representations, there is no assurance with respect to any material nonpublic information of which Michael Xie, Ken Xie and the Xie Foundation were unaware, or with respect to any material nonpublic information acquired by Michael Xie, Ken Xie and the Xie Foundation or us after the date of each such representation. Once executed, transactions under the September Xie Plan will be disclosed publicly through Form 4 and/or Form 144 filings with the SEC in accordance with applicable securities laws, rules and regulations. Except as may be required by law, we do not undertake any obligation to update or report any modification, termination, or other activity under current or future Rule 10b5-1 plans that may be adopted by Michael Xie, Ken Xie, the Xie Foundation or our other officers or directors, or their affiliated entities.
Rule 10b5-1 Arrangement Adopted	true
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Michael Xie and Ken Xie [Member]
Trading Arrangements, by Individual
Name	Michael Xie and Ken Xie
Michael Xie [Member]
Trading Arrangements, by Individual
Name	Michael Xie
Title	officers and director
Ken Xie [Member]
Trading Arrangements, by Individual
Name	Ken Xie
Title	officers and director
August Xie Plan [Member]
Trading Arrangements, by Individual
Adoption Date	August 16, 2023
August Xie Plan [Member] | Michael Xie and Ken Xie [Member]
Trading Arrangements, by Individual
Arrangement Duration	380 days
Aggregate Available	50,000	50,000
August Xie Plan [Member] | Michael Xie [Member]
Trading Arrangements, by Individual
Arrangement Duration	380 days
Aggregate Available	100,000	100,000
September Xie Plan [Member]
Trading Arrangements, by Individual
Adoption Date	September 8, 2023
September Xie Plan [Member] | Michael Xie and Ken Xie [Member]
Trading Arrangements, by Individual
Arrangement Duration	434 days
Aggregate Available	50,000	50,000
September Xie Plan [Member] | Michael Xie [Member]
Trading Arrangements, by Individual
Arrangement Duration	434 days
Aggregate Available	100,000	100,000
September Xie Plan [Member] | Ken Xie [Member]
Trading Arrangements, by Individual
Arrangement Duration	434 days
Aggregate Available	150,000	150,000

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation and Preparation	Basis of Presentation and Preparation —The unaudited condensed consolidated financial statements of Fortinet, Inc. and its 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 (the “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, 2022, contained in our Annual Report on Form 10-K filed with the SEC on February 24, 2023. In the opinion of management, all adjustments, which include normal recurring adjustments, considered necessary for a fair presentation, have been included. The results of operations for the three and nine months ended September 30, 2023 are not necessarily indicative of the results to be expected for the full year or for any future periods. The condensed consolidated balance sheet as of December 31, 2022 is derived from the audited consolidated financial statements for the year ended December 31, 2022. Amounts related to income taxes payable have been reclassified in prior periods to conform with current period presentation. The condensed consolidated financial statements include the accounts of Fortinet, Inc. and its subsidiaries. We consolidate all legal entities in which we have an absolute controlling financial interest. All intercompany balances and transactions have been eliminated in consolidation. The preparation of the condensed consolidated 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 and nine months ended September 30, 2023, as compared to the significant accounting policies described in the Form 10-K.
Recently Adopted and Recently Issued Accounting Standards	Recently Adopted and Recently Issued Accounting Standards There were no recently adopted accounting standards which would have a material effect on our condensed consolidated financial statements and accompanying disclosures, and no recently issued accounting standards that are expected to have a material impact on our condensed consolidated financial statements and accompanying disclosures.

Revenue Recognition (Tables)

Revenue Recognition (Tables)	9 Months Ended
	Sep. 30, 2023
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following table presents our revenue disaggregated by major product and service lines (in millions): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Product $ 465.9 $ 468.7 $ 1,439.2 $ 1,240.4 Service: Security subscription 494.6 369.8 1,373.6 1,023.1 Technical support and other 374.1 311.0 1,076.9 870.9 Total service revenue 868.7 680.8 2,450.5 1,894.0 Total revenue $ 1,334.6 $ 1,149.5 $ 3,889.7 $ 3,134.4

Financial Instruments and Fai_2

Financial Instruments and Fair Value (Tables)	9 Months Ended
	Sep. 30, 2023
Financial Instruments and Fair Value [Abstract]
Summary of Investments	The following tables summarize our available-for-sale securities (in millions): September 30, 2023 Amortized Unrealized Unrealized Fair U.S. government and agency securities $ 423.4 $ 0.1 $ (0.5) $ 423.0 Commercial paper 400.0 — (0.3) 399.7 Certificates of deposit and term deposits 73.5 — — 73.5 Corporate debt securities 68.0 — (0.5) 67.5 Total available-for-sale securities $ 964.9 $ 0.1 $ (1.3) $ 963.7 December 31, 2022 Amortized Unrealized Unrealized Fair U.S. government and agency securities $ 198.0 $ — $ (4.4) $ 193.6 Commercial paper 26.5 — (0.1) 26.4 Certificates of deposit and term deposits 34.2 — — 34.2 Corporate debt securities 293.0 — (4.1) 288.9 Municipal bonds 5.1 — (0.1) 5.0 Total available-for-sale securities $ 556.8 $ — $ (8.7) $ 548.1
Schedule of Unrealized Loss on Investments	The following tables show the gross unrealized losses and the related fair values of our available-for-sale securities that have been in a continuous unrealized loss position (in millions): September 30, 2023 Less Than 12 Months 12 Months or Greater Total Fair Unrealized Fair Unrealized Fair Unrealized U.S. government and agency securities $ 159.1 $ (0.1) $ 32.6 $ (0.4) $ 191.7 $ (0.5) Commercial paper 376.6 (0.3) — — 376.6 (0.3) Corporate debt securities 15.3 — 46.4 (0.5) 61.7 (0.5) Total available-for-sale securities $ 551.0 $ (0.4) $ 79.0 $ (0.9) $ 630.0 $ (1.3) December 31, 2022 Less Than 12 Months 12 Months or Greater Total Fair Unrealized Fair Unrealized Fair Unrealized U.S. government and agency securities $ 3.9 $ (0.1) $ 189.8 $ (4.3) $ 193.7 $ (4.4) Commercial paper 26.4 (0.1) — — 26.4 (0.1) Corporate debt securities 90.5 (0.8) 190.0 (3.3) 280.5 (4.1) Municipal bonds 5.0 (0.1) — — 5.0 (0.1) Total available-for-sale securities $ 125.8 $ (1.1) $ 379.8 $ (7.6) $ 505.6 $ (8.7)
Investments Classified by Contractual Maturity Date	The contractual maturities of our investments were (in millions): September 30, December 31, Due within one year $ 962.2 $ 502.6 Due within one to three years 1.5 45.5 Total $ 963.7 $ 548.1
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following tables present the fair value of our financial assets measured at fair value on a recurring basis (in millions): September 30, 2023 December 31, 2022 Aggregate Quoted Significant Significant Aggregate Quoted Significant Significant (Level 1) (Level 2) (Level 3) (Level 1) (Level 2) (Level 3) Assets: U.S. government and agency securities $ 474.1 $ 402.4 $ 71.7 $ — $ 268.6 $ 259.3 $ 9.3 $ — Commercial paper 439.5 — 439.5 — 115.8 — 115.8 — Certificates of deposit and term deposits 93.5 — 93.5 — 50.4 — 50.4 — Corporate debt securities 67.5 — 67.5 — 288.9 — 288.9 — Money market funds 325.0 325.0 — — 593.9 593.9 — — Municipal bonds — — — — 5.0 — 5.0 — Marketable equity securities 19.8 19.8 — — 25.5 25.5 — — Total $ 1,419.4 $ 747.2 $ 672.2 $ — $ 1,348.1 $ 878.7 $ 469.4 $ — Reported as: Cash equivalents $ 435.9 $ 774.5 Marketable equity securities 19.8 25.5 Short-term investments 962.2 502.6 Long-term investments 1.5 45.5 Total $ 1,419.4 $ 1,348.1

Inventory (Tables)

Inventory (Tables)	9 Months Ended
	Sep. 30, 2023
Inventory Disclosure [Abstract]
Inventory	Inventory consisted of (in millions): September 30, December 31, Raw materials $ 77.5 $ 46.3 Work in process 8.0 12.0 Finished goods 382.0 206.3 Inventory $ 467.5 $ 264.6

Property and Equipment_Net (Tab

Property and Equipment—Net (Tables)	9 Months Ended
	Sep. 30, 2023
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment - Net	Property and equipment—net consisted of (in millions): September 30, December 31, Land $ 351.7 $ 310.0 Buildings and improvements 591.7 490.3 Computer equipment and software 252.3 222.7 Leasehold improvements 60.6 53.5 Evaluation units 27.5 19.2 Furniture and fixtures 30.5 31.3 Construction-in-progress 55.8 51.7 Total property and equipment 1,370.1 1,178.7 Less: accumulated depreciation (332.1) (280.2) Property and equipment—net $ 1,038.0 $ 898.5

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets - Net (Tables)	9 Months Ended
	Sep. 30, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in Carrying Amount of Goodwill	The following table presents the changes in the carrying amount of goodwill (in millions): Amount Balance—December 31, 2022 $ 128.0 Foreign currency translation adjustments (2.6) Balance—September 30, 2023 $ 125.4
Schedule of Finite-Lived Intangible Assets by Major Class	The following tables present other intangible assets—net (in millions, except years): September 30, 2023 Weighted-Average Useful Life (in Years) Gross Accumulated Amortization Net Other intangible assets—net: Finite-lived intangible assets: Developed technologies 4.3 $ 82.3 $ 59.7 $ 22.6 Customer relationships 7.0 30.0 16.7 13.3 Trade name 10.0 4.7 1.0 3.7 Backlog 1.0 3.7 3.7 — Total other intangible assets—net $ 120.7 $ 81.1 $ 39.6 December 31, 2022 Weighted-Average Useful Life (in Years) Gross Accumulated Amortization Net Other intangible assets—net: Finite-lived intangible assets: Developed technologies 4.1 $ 85.1 $ 50.3 $ 34.8 Customer relationships 7.1 31.0 14.4 16.6 Trade name 10.0 5.3 0.7 4.6 Backlog 1.0 4.2 4.2 — Total other intangible assets—net $ 125.6 $ 69.6 $ 56.0
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The following table summarizes estimated future amortization expense of finite-lived intangible assets—net (in millions): Amount Years: 2023 (the remainder of 2023) $ 4.0 2024 12.7 2025 8.2 2026 4.1 2027 3.8 Thereafter 6.8 Total $ 39.6

Net Income Per Share (Tables)

Net Income Per Share (Tables)	9 Months Ended
	Sep. 30, 2023
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	A reconciliation of the numerator and denominator used in the calculation of basic and diluted net income per share attributable to Fortinet, Inc. is (in millions, except per share amounts): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Numerator: Net income including non-controlling interests $ 322.9 $ 231.1 $ 836.9 $ 542.8 Net loss attributable to non-controlling interests — (0.5) — (0.7) Net income attributable to Fortinet, Inc. $ 322.9 $ 231.6 $ 836.9 $ 543.5 Denominator: Basic shares: Weighted-average common stock outstanding-basic 781.2 786.2 783.1 795.0 Diluted shares: Weighted-average common stock outstanding-basic 781.2 786.2 783.1 795.0 Effect of potentially dilutive securities: RSUs 3.5 4.9 3.8 6.6 Stock options 6.2 7.5 6.4 8.2 PSUs 0.3 — 0.2 — Weighted-average shares used to compute diluted net income per share attributable to Fortinet, Inc. 791.2 798.6 793.5 809.8 Net income per share attributable to Fortinet, Inc.: Basic $ 0.41 $ 0.29 $ 1.07 $ 0.68 Diluted $ 0.41 $ 0.29 $ 1.05 $ 0.67
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following weighted-average shares of common stock were excluded from the computation of diluted net income per share attributable to Fortinet, Inc. for the periods presented, as their effect would have been antidilutive (in millions): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, RSUs — 2.5 0.6 1.1 Stock options 3.0 1.6 2.8 1.4 Total 3.0 4.1 3.4 2.5

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2023
Debt Disclosure [Abstract]
Summary of Outstanding Debt	The total outstanding debt is summarized below (in millions, except percentages): Maturity Coupon Rate Effective Interest Rate September 30, December 31, Debt 2026 Senior Notes March 2026 1.0% 1.3% $ 500.0 $ 500.0 2031 Senior Notes March 2031 2.2% 2.3% 500.0 500.0 Total debt 1,000.0 1,000.0 Less: Unamortized discount and debt issuance costs 8.2 9.6 Total long-term debt $ 991.8 $ 990.4

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Inventory Purchase Commitments, Fiscal Year Maturity Schedule	The following table summarizes our inventory purchase commitments as of September 30, 2023 (in millions): Total 2023 Thereafter Inventory purchase commitments $ 820.6 $ 608.5 $ 212.1

Equity Plans and Share Repurc_2

Equity Plans and Share Repurchase Program (Tables)	9 Months Ended
	Sep. 30, 2023
Share-Based Payment Arrangement [Abstract]
Schedule of Share-based Compensation, Restricted Stock Units Award Activity	The following table summarizes the activity and related information for RSUs for the periods presented below (in millions, except per share amounts): Restricted Stock Units Outstanding Number of Shares Weighted-Average Grant Date Fair Value per Share Balance—December 31, 2022 10.5 $ 40.94 Granted 4.5 60.85 Forfeited (0.6) 48.33 Vested (4.3) 34.88 Balance—September 30, 2023 10.1 $ 51.91
Schedule of Share-based Compensation, Shares Withheld for Taxes	The following summarizes the number and value of the shares withheld for employee taxes (in millions): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Shares withheld for taxes 0.4 0.5 1.5 2.2 Amount withheld for taxes $ 31.0 $ 32.0 $ 90.7 $ 132.1
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The following table summarizes the weighted-average assumptions relating to our employee stock options: Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Expected term in years 4.4 4.4 4.4 4.4 Volatility 42.8 % 42.5 % 42.0 % 41.2 % Risk-free interest rate 4.5 % 3.1 % 4.2 % 2.0 % 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 millions, except exercise prices and contractual life): Options Outstanding Number Weighted- Weighted- Aggregate Balance—December 31, 2022 13.2 $ 24.37 3.5 $ 344.8 Granted 1.3 60.59 Forfeited (0.1) 47.86 Exercised (2.4) 14.89 Balance—September 30, 2023 12.0 $ 29.95 Options vested and expected to vest—September 30, 2023 12.0 $ 29.95 3.4 $ 350.2 Options exercisable—September 30, 2023 8.4 $ 21.24 2.6 $ 317.9
Schedule of Share-based Compensation, Stock Options, Activity, Additional Information	Additional information related to our stock options is summarized below (in millions, except per share amounts): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Weighted-average fair value per share granted $ 23.67 $ 20.22 $ 24.37 $ 22.09 Intrinsic value of options exercised $ 13.9 $ 29.7 $ 110.9 $ 73.3 Fair value of options vested $ 6.1 $ 4.8 $ 23.5 $ 19.8
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions	The following table summarizes the weighted-average assumptions relating to our PSUs for the three months ended March 31, 2023: Three Months Ended March 31, Expected term in years 2.7 Volatility 47.5 % Risk-free interest rate 4.6 % Dividend rate — %
Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs	Stock-based compensation expense, including stock-based compensation expense related to awards classified as liabilities, is included in costs and expenses (in millions): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Cost of product revenue $ 0.4 $ 0.5 $ 1.3 $ 1.3 Cost of service revenue 6.1 4.8 17.2 14.0 Research and development 20.0 16.7 57.0 47.9 Sales and marketing 28.5 25.9 84.1 79.0 General and administrative 9.9 7.4 28.0 22.3 Total stock-based compensation expense $ 64.9 $ 55.3 $ 187.6 $ 164.5
Schedule of Employee Service Share based Compensation Allocation of Recognized Period Costs by Award Type	The following table summarizes stock-based compensation expense, including stock-based compensation expense related to awards classified as liabilities, by award type (in millions): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, RSUs $ 54.2 $ 48.9 $ 158.4 $ 146.2 Stock options 7.5 6.4 21.5 18.3 PSUs 3.2 — 7.7 — Total stock-based compensation expense $ 64.9 $ 55.3 $ 187.6 $ 164.5
Income Tax Benefit from Stock Option Plans	Total income tax benefit associated with stock-based compensation that is recognized in the condensed consolidated statements of income is as follows (in millions): Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Income tax benefit associated with stock-based compensation $ 14.3 $ 12.2 $ 41.4 $ 36.2

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2023
Segment Reporting [Abstract]
Revenue From External Customers by Geographic Region	Revenue by geographic region is based on the billing address of our customers. The following tables set forth revenue and property and equipment—net by geographic region (in millions): Three Months Ended Nine Months Ended Revenue September 30, September 30, September 30, September 30, Americas: United States $ 400.8 $ 344.1 $ 1,189.6 $ 942.8 Other Americas 144.8 123.5 416.5 321.0 Total Americas 545.6 467.6 1,606.1 1,263.8 Europe, Middle East and Africa (“EMEA”) 512.2 443.9 1,497.3 1,181.7 Asia Pacific (“APAC”) 276.8 238.0 786.3 688.9 Total revenue $ 1,334.6 $ 1,149.5 $ 3,889.7 $ 3,134.4
Property and Equipment by Geographic Region	Property and Equipment — net September 30, December 31, Americas: United States $ 696.7 $ 638.1 Canada 209.8 204.4 Latin America 1.2 1.1 Total Americas 907.7 843.6 EMEA 68.7 35.9 APAC 61.6 19.0 Total property and equipment—net $ 1,038.0 $ 898.5
Schedule of Distributor Concentration	The following distributors accounted for 10% or more of our revenue: Three Months Ended Nine Months Ended September 30, September 30, September 30, September 30, Distributor A 28 % 29 % 28 % 29 % Distributor B 15 % 13 % 15 % 13 % Distributor C 13 % 13 % 14 % 13 % The following distributors accounted for 10% or more of net accounts receivable: September 30, December 31, Distributor A 26 % 32 % Distributor B 13 % 12 % Distributor C 13 % 13 %

Revenue Recognition - Disaggreg

Revenue Recognition - Disaggregated Revenues (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Total revenue	$ 1,334.6	$ 1,149.5	$ 3,889.7	$ 3,134.4
Product
Disaggregation of Revenue [Line Items]
Total revenue	465.9	468.7	1,439.2	1,240.4
Service
Disaggregation of Revenue [Line Items]
Total revenue	868.7	680.8	2,450.5	1,894
Security subscription
Disaggregation of Revenue [Line Items]
Total revenue	494.6	369.8	1,373.6	1,023.1
Technical support and other
Disaggregation of Revenue [Line Items]
Total revenue	$ 374.1	$ 311	$ 1,076.9	$ 870.9

Revenue Recognition - Additiona

Revenue Recognition - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Threshold period past due	60 days		60 days
Allowance for credit losses	$ 5.3		$ 5.3		$ 3.6
Amortization of deferred contract costs	68	$ 56.7	195.9	$ 163.8
Service
Disaggregation of Revenue [Line Items]
Deferred revenue recognized in period	$ 514.3	$ 401.9	$ 1,800	$ 1,370

Revenue Recognition - Performan

Revenue Recognition - Performance Obligation Satisfaction Period (Details) $ in Millions	Sep. 30, 2023 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 5,300
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 2,660
Performance obligation expected recognition period for three-fourths of remaining obligation	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Remaining performance obligation	$ 2,640
Performance obligation expected recognition period for three-fourths of remaining obligation

Financial Instruments and Fai_3

Financial Instruments and Fair Value , Investments (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 964.9	$ 556.8
Unrealized Gains	0.1	0
Unrealized Losses	(1.3)	(8.7)
Fair Value	963.7	548.1
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	551	125.8
Less Than 12 Months, Unrealized Losses	(0.4)	(1.1)
12 Months or Greater, Fair Value	79	379.8
12 Months or Greater, Unrealized Losses	(0.9)	(7.6)
Total, Fair Value	630	505.6
Total, Unrealized Losses	(1.3)	(8.7)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Due within one year	962.2	502.6
Due within one to three years	1.5	45.5
Fair Value	963.7	548.1
U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	423.4	198
Unrealized Gains	0.1	0
Unrealized Losses	(0.5)	(4.4)
Fair Value	423	193.6
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	159.1	3.9
Less Than 12 Months, Unrealized Losses	(0.1)	(0.1)
12 Months or Greater, Fair Value	32.6	189.8
12 Months or Greater, Unrealized Losses	(0.4)	(4.3)
Total, Fair Value	191.7	193.7
Total, Unrealized Losses	(0.5)	(4.4)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	423	193.6
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	400	26.5
Unrealized Gains	0	0
Unrealized Losses	(0.3)	(0.1)
Fair Value	399.7	26.4
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	376.6	26.4
Less Than 12 Months, Unrealized Losses	(0.3)	(0.1)
12 Months or Greater, Fair Value	0	0
12 Months or Greater, Unrealized Losses	0	0
Total, Fair Value	376.6	26.4
Total, Unrealized Losses	(0.3)	(0.1)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	399.7	26.4
Certificates of deposit and term deposits
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	73.5	34.2
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	73.5	34.2
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	73.5	34.2
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	68	293
Unrealized Gains	0	0
Unrealized Losses	(0.5)	(4.1)
Fair Value	67.5	288.9
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value	15.3	90.5
Less Than 12 Months, Unrealized Losses	0	(0.8)
12 Months or Greater, Fair Value	46.4	190
12 Months or Greater, Unrealized Losses	(0.5)	(3.3)
Total, Fair Value	61.7	280.5
Total, Unrealized Losses	(0.5)	(4.1)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value	$ 67.5	288.9
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		5.1
Unrealized Gains		0
Unrealized Losses		(0.1)
Fair Value		5
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months, Fair Value		5
Less Than 12 Months, Unrealized Losses		(0.1)
12 Months or Greater, Fair Value		0
12 Months or Greater, Unrealized Losses		0
Total, Fair Value		5
Total, Unrealized Losses		(0.1)
Available-for-sale Securities, Debt Maturities, Fair Value [Abstract]
Fair Value		$ 5

Financial Instruments and Fai_4

Financial Instruments and Fair Value , Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 963.7		$ 963.7		$ 548.1
Recognized gain (loss) on marketable equity securities	(2.3)	$ 2.6	(5.7)	$ (11.7)
Marketable equity securities | Reported as [Member] | Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 19.8		$ 19.8		$ 25.5

Financial Instruments and Fai_5

Financial Instruments and Fair Value , Fair Value Measurements (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 963.7	$ 548.1
U.S. government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	423	193.6
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	399.7	26.4
Certificates of deposit and term deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	73.5	34.2
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	67.5	288.9
Municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value		5
Recurring Basis [Member] | Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	1,419.4	1,348.1
Recurring Basis [Member] | Fair Value [Member] | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	747.2	878.7
Recurring Basis [Member] | Fair Value [Member] | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	672.2	469.4
Recurring Basis [Member] | Fair Value [Member] | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	0	0
Recurring Basis [Member] | Fair Value [Member] | U.S. government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	474.1	268.6
Recurring Basis [Member] | Fair Value [Member] | U.S. government and agency securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	402.4	259.3
Recurring Basis [Member] | Fair Value [Member] | U.S. government and agency securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	71.7	9.3
Recurring Basis [Member] | Fair Value [Member] | U.S. government and agency securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring Basis [Member] | Fair Value [Member] | Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	439.5	115.8
Recurring Basis [Member] | Fair Value [Member] | Commercial paper | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring Basis [Member] | Fair Value [Member] | Commercial paper | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	439.5	115.8
Recurring Basis [Member] | Fair Value [Member] | Commercial paper | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring Basis [Member] | Fair Value [Member] | Certificates of deposit and term deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	93.5	50.4
Recurring Basis [Member] | Fair Value [Member] | Certificates of deposit and term deposits | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring Basis [Member] | Fair Value [Member] | Certificates of deposit and term deposits | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	93.5	50.4
Recurring Basis [Member] | Fair Value [Member] | Certificates of deposit and term deposits | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring Basis [Member] | Fair Value [Member] | Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	67.5	288.9
Recurring Basis [Member] | Fair Value [Member] | Corporate debt securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring Basis [Member] | Fair Value [Member] | Corporate debt securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	67.5	288.9
Recurring Basis [Member] | Fair Value [Member] | Corporate debt securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring Basis [Member] | Fair Value [Member] | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	325	593.9
Recurring Basis [Member] | Fair Value [Member] | Money market funds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	325	593.9
Recurring Basis [Member] | Fair Value [Member] | Money market funds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring Basis [Member] | Fair Value [Member] | Money market funds | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring Basis [Member] | Fair Value [Member] | Municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	5
Recurring Basis [Member] | Fair Value [Member] | Municipal bonds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring Basis [Member] | Fair Value [Member] | Municipal bonds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	5
Recurring Basis [Member] | Fair Value [Member] | Municipal bonds | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring Basis [Member] | Fair Value [Member] | Marketable equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	19.8	25.5
Recurring Basis [Member] | Fair Value [Member] | Marketable equity securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	19.8	25.5
Recurring Basis [Member] | Fair Value [Member] | Marketable equity securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring Basis [Member] | Fair Value [Member] | Marketable equity securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	0	0
Recurring Basis [Member] | Reported as [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Assets, Fair Value Disclosure	1,419.4	1,348.1
Recurring Basis [Member] | Reported as [Member] | Cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	435.9	774.5
Recurring Basis [Member] | Reported as [Member] | Marketable equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	19.8	25.5
Recurring Basis [Member] | Reported as [Member] | Short-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	962.2	502.6
Recurring Basis [Member] | Reported as [Member] | Long-term investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	$ 1.5	$ 45.5

Inventory (Details)

Inventory (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Inventory, Net [Abstract]
Raw materials	$ 77.5	$ 46.3
Work in process	8	12
Finished goods	382	206.3
Inventory	$ 467.5	$ 264.6

Property and Equipment_Net (Det

Property and Equipment—Net (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	$ 1,370.1			$ 1,370.1		$ 1,178.7
Less: accumulated depreciation	(332.1)			(332.1)		(280.2)
Property and equipment—net	1,038			1,038		898.5
Purchase of property and equipment				177.2	$ 250.3
Depreciation expense	23.9		$ 21.2	69.6	$ 59.4
Spain and U.S.
Property, Plant and Equipment, Net, by Type [Abstract]
Purchase of property and equipment		$ 51.9
Australia
Property, Plant and Equipment, Net, by Type [Abstract]
Purchase of property and equipment	41.3
Land
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	351.7			351.7		310
Land | Spain and U.S.
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment		6.5
Land | Australia
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	21.5			21.5
Buildings and improvements
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	591.7			591.7		490.3
Buildings and improvements | Spain and U.S.
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment		$ 45.4
Computer equipment and software
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	252.3			252.3		222.7
Leasehold improvements
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	60.6			60.6		53.5
Evaluation units
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	27.5			27.5		19.2
Furniture and fixtures
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	30.5			30.5		31.3
Construction-in-progress
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	55.8			55.8		$ 51.7
Construction-in-progress | Australia
Property, Plant and Equipment, Net, by Type [Abstract]
Total property and equipment	$ 19.8			$ 19.8

Investments in Privately Held_2

Investments in Privately Held Companies (Details) - USD ($) $ in Millions		3 Months Ended			9 Months Ended		12 Months Ended
	Aug. 01, 2023	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Cash investment in privately held company					$ 8.5	$ 0
Loss from equity method investments		$ (5.2)		$ (6.3)	(32.6)	$ (22.9)
Linksys
Schedule of Equity Method Investments [Line Items]
Cash investment in privately held company							$ 160
Ownership interest percentage							50.80%
Equity method investment carrying value		$ 51.6	$ 84.3		$ 51.6
Other than temporary impairment charge			22.2
Valuation allowance on deferred tax assets related to equity method investment			$ 17.5
Privately Held Company
Schedule of Equity Method Investments [Line Items]
Cash investment in privately held company	$ 8.5
Ownership interest percentage	19.50%

Business Combinations - Additio

Business Combinations - Additional Information (Details) - Alaxala - USD ($) $ in Millions	Oct. 03, 2022	Aug. 31, 2021
Business Acquisition [Line Items]
Equity interests acquired	25%	75%
Cash consideration	$ 13.5	$ 64.2

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Net - Changes in Carrying Amount of Goodwill (Details) $ in Millions	9 Months Ended
	Sep. 30, 2023 USD ($)
Goodwill [Roll Forward]
Balance - beginning of period	$ 128
Foreign currency translation adjustments	(2.6)
Balance - end of period	$ 125.4

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Net - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill impairment			$ 0	$ 0
Amortization expense	$ 4,400,000	$ 5,200,000	$ 13,600,000	$ 17,600,000

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets - Net - Other Intangible Assets, Net (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 120.7	$ 125.6
Accumulated Amortization	81.1	69.6
Total	$ 39.6	$ 56
Developed technologies
Finite-Lived Intangible Assets [Line Items]
Weighted-Average Useful Life (in Years)	4 years 3 months 18 days	4 years 1 month 6 days
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 82.3	$ 85.1
Accumulated Amortization	59.7	50.3
Total	$ 22.6	$ 34.8
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Weighted-Average Useful Life (in Years)	7 years	7 years 1 month 6 days
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 30	$ 31
Accumulated Amortization	16.7	14.4
Total	$ 13.3	$ 16.6
Trade name
Finite-Lived Intangible Assets [Line Items]
Weighted-Average Useful Life (in Years)	10 years	10 years
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 4.7	$ 5.3
Accumulated Amortization	1	0.7
Total	$ 3.7	$ 4.6
Backlog
Finite-Lived Intangible Assets [Line Items]
Weighted-Average Useful Life (in Years)	1 year	1 year
Finite-Lived Intangible Assets, Net [Abstract]
Gross	$ 3.7	$ 4.2
Accumulated Amortization	3.7	4.2
Total	$ 0	$ 0

Goodwill and Other Intangible_6

Goodwill and Other Intangible Assets - Net - Estimated Future Amortization Expense (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Fiscal Years:
2023 (the remainder of 2023)	$ 4
2024	12.7
2025	8.2
2026	4.1
2027	3.8
Thereafter	6.8
Total	$ 39.6	$ 56

Net Income Per Share , Calculat

Net Income Per Share , Calculation of Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Earnings Per Share [Line Items]
Net income including non-controlling interests	$ 322.9	$ 231.1	$ 836.9	$ 542.8
Net loss attributable to non-controlling interests	0	(0.5)	0	(0.7)
Net income	$ 322.9	$ 231.6	$ 836.9	$ 543.5
Basic shares:
Weighted-average common shares outstanding-basic (in shares)	781.2	786.2	783.1	795
Diluted shares:
Weighted-average common shares outstanding-basic (in shares)	781.2	786.2	783.1	795
Effect of potentially dilutive securities:
Weighted-average shares used to compute diluted net income per share (in shares)	791.2	798.6	793.5	809.8
Net income per share attributable to Fortinet, Inc.:
Basic (in dollars per share)	$ 0.41	$ 0.29	$ 1.07	$ 0.68
Diluted (in dollars per share)	$ 0.41	$ 0.29	$ 1.05	$ 0.67
RSUs
Effect of potentially dilutive securities:
RSUs and stock options (in shares)	3.5	4.9	3.8	6.6
Stock options
Effect of potentially dilutive securities:
RSUs and stock options (in shares)	6.2	7.5	6.4	8.2
PSUs
Effect of potentially dilutive securities:
RSUs and stock options (in shares)	0.3	0	0.2	0

Net Income Per Share , Anti Dil

Net Income Per Share , Anti Dilutive Securities (Details) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	3	4.1	3.4	2.5
RSUs | Share-based Payment Arrangement
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	0	2.5	0.6	1.1
Stock options | Share-based Payment Arrangement
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	3	1.6	2.8	1.4

Debt - Narrative (Details)

Debt - Narrative (Details) - Senior Notes - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Mar. 05, 2021
Debt Instrument [Line Items]
Aggregate principal amount						$ 1,000,000,000
Accrued interest payable	$ 700,000		$ 700,000		$ 4,700,000
Interest expense	4,500,000	$ 4,400,000	13,500,000	$ 13,400,000
Interest costs capitalized			0	$ 0
Level 2
Debt Instrument [Line Items]
Estimated fair value of outstanding debt	$ 834,800,000		$ 834,800,000
2026 Senior Notes
Debt Instrument [Line Items]
Aggregate principal amount						$ 500,000,000
Stated interest rate	1%		1%			1%
2031 Senior Notes
Debt Instrument [Line Items]
Aggregate principal amount						$ 500,000,000
Stated interest rate	2.20%		2.20%			2.20%

Debt - Summary of Outstanding D

Debt - Summary of Outstanding Debt (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Mar. 05, 2021
Debt Instrument [Line Items]
Total debt	$ 1,000	$ 1,000
Less: Unamortized discount and debt issuance costs	8.2	9.6
LONG-TERM DEBT	$ 991.8	990.4
Senior Notes | 2026 Senior Notes
Debt Instrument [Line Items]
Coupon Rate	1%		1%
Effective Interest Rate	1.30%
Total debt	$ 500	500
Senior Notes | 2031 Senior Notes
Debt Instrument [Line Items]
Coupon Rate	2.20%		2.20%
Effective Interest Rate	2.30%
Total debt	$ 500	$ 500

Commitments and Contingencies -

Commitments and Contingencies - Summary of Inventory Purchase Commitments (Details) $ in Millions	Sep. 30, 2023 USD ($)
Inventory purchase commitments
Total	$ 820.6
2023	608.5
Thereafter	$ 212.1

Commitments and Contingencies_2

Commitments and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2023	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Inventory purchase commitments	$ 820.6	$ 820.6
Accrued inventory purchase commitments	64.6	64.6	$ 0
Inventory purchase expense	36.9	59.3
Other contractual commitments and open purchase orders	76.8	$ 76.8
Non-cancelable remaining contract term (in excess of)		1 year
Operating lease liability	$ 89.5	$ 89.5

Equity Plans and Share Repurc_3

Equity Plans and Share Repurchase Program (Deficit) , Restricted Stock Units Activity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Weighted-Average Grant Date Fair Value per Share
Shares withheld for taxes	0.4	0.5	1.5	2.2
Amount withheld for taxes	$ 31	$ 32	$ 90.7	$ 132.1
Stock-based Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining shares available for grant under the plans	53.3		53.3
RSUs
Number of Shares
Balance, beginning (shares)			10.5
Granted (shares)			4.5
Forfeited (shares)			(0.6)
Vested (shares)			(4.3)
Balance, ending (shares)	10.1		10.1
Weighted-Average Grant Date Fair Value per Share
Balance, beginning (in dollars per share)			$ 40.94
Granted (in dollars per share)			60.85
Forfeited (in dollars per share)			48.33
Vested (in dollars per share)			34.88
Balance, ending (in dollars per share)	$ 51.91		$ 51.91
Compensation cost not yet recognized	$ 460.9		$ 460.9
Compensation cost not yet recognized period of recognition			2 years 8 months 12 days

Equity Plans and Share Repurc_4

Equity Plans and Share Repurchase Program (Deficit) - Employee Stock Options (Details) - Stock options - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected term in years	4 years 4 months 24 days	4 years 4 months 24 days	4 years 4 months 24 days	4 years 4 months 24 days
Volatility	42.80%	42.50%	42%	41.20%
Risk-free interest rate	4.50%	3.10%	4.20%	2%
Dividend rate	0%	0%	0%	0%
Number of Shares
Balance - Beginning (in shares)			13.2
Granted (in shares)			1.3
Forfeited (in shares)			(0.1)
Exercised (in shares)			(2.4)
Balance - Ending (in shares)	12		12		13.2
Weighted- Average Exercise Price
Balance - Beginning (in dollars per share)			$ 24.37
Granted (in dollars per share)			60.59
Forfeited (in dollars per share)			47.86
Exercised (in dollars per share)			14.89
Balance - Ending (in dollars per share)	$ 29.95		$ 29.95		$ 24.37
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options outstanding, Weighted average remaining contractual life (in years)					3 years 6 months
Options outstanding, Aggregate intrinsic value					$ 344.8
Options vested and expected to vest, Outstanding (in shares)	12		12
Options vested and expected to vest, Weighted average exercise price (in dollars per share)	$ 29.95		$ 29.95
Options vested and expected to vest, Weighted average remaining contractual life (in years)			3 years 4 months 24 days
Options vested and expected to vest, Aggregate intrinsic value	$ 350.2		$ 350.2
Options exercisable, Outstanding (in shares)	8.4		8.4
Options exercisable, Weighted average exercise price (in dollars per share)	$ 21.24		$ 21.24
Options exercisable, Weighted average remaining contractual life (in years)			2 years 7 months 6 days
Options exercisable, Aggregate intrinsic value	$ 317.9		$ 317.9
Compensation cost not yet recognized	$ 61.4		$ 61.4
Compensation cost not yet recognized period of recognition			2 years 7 months 6 days
Weighted-average fair value per share granted	$ 23.67	$ 20.22	$ 24.37	$ 22.09
Intrinsic value of options exercised	$ 13.9	$ 29.7	$ 110.9	$ 73.3
Fair value of options vested	$ 6.1	$ 4.8	$ 23.5	$ 19.8

Equity Plans and Share Repurc_5

Equity Plans and Share Repurchase Program (Deficit) , Market Based PSUs (Details) - PSUs - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended	9 Months Ended
	Mar. 31, 2023	Sep. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term in years	2 years 8 months 12 days
Volatility	47.50%
Risk-free interest rate	4.60%
Dividend rate	0%
Granted (shares)	0.3
Granted (in dollars per share)	$ 90.96
Forfeited (shares)		0
Vested (shares)		0
Compensation cost not yet recognized		$ 19.4
Compensation cost not yet recognized period of recognition		2 years 4 months 24 days
Share-Based Payment Arrangement, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period		1 year
Vesting percentage		20%
Award vesting period		1 year
Share-Based Payment Arrangement, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period		2 years
Vesting percentage		20%
Award vesting period		2 years
Share-Based Payment Arrangement, Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period		3 years
Vesting percentage		20%
Award vesting period		3 years
Share-Based Payment Arrangement, Tranche Four
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period		4 years
Vesting percentage		40%
Award vesting period		4 years
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Market-based vesting percentage range		0%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Market-based vesting percentage range		200%

Equity Plans and Share Repurc_6

Equity Plans and Share Repurchase Program (Deficit) , Allocation of Stock-Based Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 64.9	$ 55.3	$ 187.6	$ 164.5
Income tax benefit associated with stock-based compensation	14.3	12.2	41.4	36.2
RSUs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	54.2	48.9	158.4	146.2
Stock options
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	7.5	6.4	21.5	18.3
PSUs
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	3.2	0	7.7	0
Cost of product revenue
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	0.4	0.5	1.3	1.3
Cost of service revenue
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	6.1	4.8	17.2	14
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	20	16.7	57	47.9
Sales and marketing
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	28.5	25.9	84.1	79
General and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 9.9	$ 7.4	$ 28	$ 22.3

Equity Plans and Share Repurc_7

Equity Plans and Share Repurchase Program (Deficit) , Share Repurchase Program (Details) - USD ($) $ / shares in Units, shares in Millions	1 Months Ended		3 Months Ended		9 Months Ended
	Jul. 31, 2023	Apr. 30, 2023	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Share Repurchase Program [Line Items]
Stock repurchased in the period, aggregate purchase price			$ 605,200,000	$ 500,000,000	$ 605,200,000	$ 1,991,200,000
Stock repurchase, excise tax			2,800,000		$ 2,800,000
Repurchase Program
Share Repurchase Program [Line Items]
Increase in authorized stock repurchase amount	$ 500,000,000	$ 1,000,000,000
Stock repurchase program, authorized amount	$ 6,750,000,000
Stock repurchased in the period (in shares)					10.4
Stock repurchased, average price (in dollars per share)					$ 58.43
Stock repurchased in the period, aggregate purchase price					$ 605,200,000
Stock repurchase, excise tax					2,800,000
Stock repurchase program, unused balance			$ 1,420,000,000		$ 1,420,000,000

Income Taxes , Narrative (Detai

Income Taxes , Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Effective tax rate (percent)	0%	10%	5%	4%
U.S. federal and state taxes, withholding taxes and foreign taxes	$ 50.2	$ 75.5	$ 220.9	$ 169.2
Tax benefit from foreign-derived intangible income deduction	41.9	28.9	105.9	62.6
Excess tax benefits on stock compensation	8.6	$ 19.3	48.3	68.7
Release of reserves on uncertain tax positions and interest due			18.1	$ 16.3
Unrecognized tax benefits	65.8		65.8		$ 67.4
Unrecognized tax benefits that would favorably affect effective tax rate	55.9		55.9
Accrued interest and penalties related to uncertain tax benefits	5.9		5.9		$ 9.3
Possible decrease in unrecognized tax benefits	$ 1.8		1.8
Income tax provision adjustment			$ (39.8)

Defined Contribution Plans (Det

Defined Contribution Plans (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Retirement Benefits [Abstract]
Matching contribution on employee contributions, Percent			50%
Maximum contribution percentage of each employee's eligible earnings, Percent			4%
Matching contributions to the RRSP and 401(k) Plans	$ 3.8	$ 3.2	$ 13.9	$ 9.8

Segment Information (Details)

Segment Information (Details) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) business_activity operating_segment reportable_segment segment_manager	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)
Segment Reporting Information [Line Items]
Business activity (in business activities) | business_activity			1
Segment managers responsible for operations (in segment managers) | segment_manager			0
Number of operating segments (in operating segments) | operating_segment			1
Number of reportable segments (in reportable segments) | reportable_segment			1
Total revenue	$ 1,334.6	$ 1,149.5	$ 3,889.7	$ 3,134.4
Property and equipment - net	$ 1,038		$ 1,038		$ 898.5
Distributor A | Customer Concentration Risk | Revenue
Segment Reporting Information [Line Items]
Concentration (percent)	28%	29%	28%	29%
Distributor A | Customer Concentration Risk | Accounts Receivable
Segment Reporting Information [Line Items]
Concentration (percent)			26%		32%
Distributor B | Customer Concentration Risk | Revenue
Segment Reporting Information [Line Items]
Concentration (percent)	15%	13%	15%	13%
Distributor B | Customer Concentration Risk | Accounts Receivable
Segment Reporting Information [Line Items]
Concentration (percent)			13%		12%
Distributor C | Customer Concentration Risk | Revenue
Segment Reporting Information [Line Items]
Concentration (percent)	13%	13%	14%	13%
Distributor C | Customer Concentration Risk | Accounts Receivable
Segment Reporting Information [Line Items]
Concentration (percent)			13%		13%
Americas
Segment Reporting Information [Line Items]
Total revenue	$ 545.6	$ 467.6	$ 1,606.1	$ 1,263.8
Property and equipment - net	907.7		907.7		$ 843.6
United States
Segment Reporting Information [Line Items]
Total revenue	400.8	344.1	1,189.6	942.8
Property and equipment - net	696.7		696.7		638.1
Canada
Segment Reporting Information [Line Items]
Property and equipment - net	209.8		209.8		204.4
Other Americas
Segment Reporting Information [Line Items]
Total revenue	144.8	123.5	416.5	321
Latin America
Segment Reporting Information [Line Items]
Property and equipment - net	1.2		1.2		1.1
EMEA
Segment Reporting Information [Line Items]
Total revenue	512.2	443.9	1,497.3	1,181.7
Property and equipment - net	68.7		68.7		35.9
APAC
Segment Reporting Information [Line Items]
Total revenue	276.8	$ 238	786.3	$ 688.9
Property and equipment - net	$ 61.6		$ 61.6		$ 19

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Nov. 06, 2023	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Subsequent Event [Line Items]
Stock repurchased in the period, aggregate purchase price		$ 605.2	$ 500	$ 605.2	$ 1,991.2
Stock repurchase, excise tax		$ 2.8		$ 2.8
Repurchase Program
Subsequent Event [Line Items]
Stock repurchased in the period (in shares)				10.4
Stock repurchased, average price (in dollars per share)				$ 58.43
Stock repurchased in the period, aggregate purchase price				$ 605.2
Stock repurchase, excise tax				$ 2.8
Subsequent Event | Repurchase Program
Subsequent Event [Line Items]
Stock repurchased in the period (in shares)	11.2
Stock repurchased, average price (in dollars per share)	$ 54.87
Stock repurchased in the period, aggregate purchase price	$ 613.5
Stock repurchase, excise tax	$ 5.7