XML 35 R25.htm IDEA: XBRL DOCUMENT
v3.25.3

Financial Instruments and Fair Value (Tables) | 9 Months Ended
--- | ---
Sep. 30, 2025
Financial Instruments and Fair Value [Abstract] |
Summary of Investments | The following tables summarize our short-term and long-term investments (in millions):
| September 30, 2025
| Amortized Cost |  | Unrealized Gains |  | Unrealized Losses |  | Fair Value
U.S. government and agency securities | $ | 560.0 |  |  | $ | 0.6 |  |  | $ | (0.1) |  |  | $ | 560.5 |
Commercial paper | 370.4 |  |  | 0.1 |  |  | — |  |  | 370.5 |
Corporate debt securities | 285.2 |  |  | 0.3 |  |  | (0.1) |  |  | 285.4 |
Certificates of deposit and term deposits | 102.2 |  |  | 0.1 |  |  | — |  |  | 102.3 |
Total available-for-sale investments | 1,317.8 |  |  | 1.1 |  |  | (0.2) |  |  | 1,318.7 |
Marketable equity securities |  |  |  |  |  |  | 98.1 |
Total short-term and long-term investments | $ | 1,317.8 |  |  | $ | 1.1 |  |  | $ | (0.2) |  |  | $ | 1,416.8 |
| December 31, 2024
| Amortized Cost |  | Unrealized Gains |  | Unrealized Losses |  | Fair Value
U.S. government and agency securities | $ | 469.1 |  |  | $ | 0.4 |  |  | $ | — |  |  | $ | 469.5 |
Commercial paper | 428.7 |  |  | 0.2 |  |  | (0.2) |  |  | 428.7 |
Corporate debt securities | 166.4 |  |  | 0.1 |  |  | (0.1) |  |  | 166.4 |
Certificates of deposit and term deposits | 61.8 |  |  | — |  |  | — |  |  | 61.8 |
Total available-for-sale investments | 1,126.0 |  |  | 0.7 |  |  | (0.3) |  |  | 1,126.4 |
Marketable equity securities |  |  |  |  |  |  | 64.2 |
Total short-term and long-term investments | $ | 1,126.0 |  |  | $ | 0.7 |  |  | $ | (0.3) |  |  | $ | 1,190.6 |
Schedule of Unrealized Loss on Investments | The following tables show the gross unrealized losses and the related fair values of our available-for-sale investments that have been in a continuous unrealized loss position (in millions):
| September 30, 2025
| Less Than 12 Months |  | 12 Months or Greater |  | Total
| Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses
U.S. government and agency securities | $ | 560.5 |  |  | $ | (0.1) |  |  | $ | — |  |  | $ | — |  |  | $ | 560.5 |  |  | $ | (0.1) |
Commercial paper | 370.5 |  |  | — |  |  | — |  |  | — |  |  | 370.5 |  |  | — |
Corporate debt securities | 285.4 |  |  | (0.1) |  |  | — |  |  | — |  |  | 285.4 |  |  | (0.1) |
Certificates of deposit and term deposits | 102.3 |  |  | — |  |  | — |  |  | — |  |  | 102.3 |  |  | — |
Total available-for-sale investments | $ | 1,318.7 |  |  | $ | (0.2) |  |  | $ | — |  |  | $ | — |  |  | $ | 1,318.7 |  |  | $ | (0.2) |
| December 31, 2024
| Less Than 12 Months |  | 12 Months or Greater |  | Total
| Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses |  | Fair Value |  | Unrealized Losses
U.S. government and agency securities | $ | 27.8 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 27.8 |  |  | $ | — |
Commercial paper | 149.4 |  |  | (0.2) |  |  | — |  |  | — |  |  | 149.4 |  |  | (0.2) |
Corporate debt securities | 63.5 |  |  | (0.1) |  |  | — |  |  | — |  |  | 63.5 |  |  | (0.1) |
Certificates of deposit and term deposits | 10.9 |  |  | — |  |  | — |  |  | — |  |  | 10.9 |  |  | — |
Total available-for-sale investments | $ | 251.6 |  |  | $ | (0.3) |  |  | $ | — |  |  | $ | — |  |  | $ | 251.6 |  |  | $ | (0.3) |
Investments Classified by Contractual Maturity Date | The contractual maturities of our available-for-sale investments were (in millions):
| September 30, 2025 |  | December 31, 2024
Due within one year | $ | 1,029.6 |  |  | $ | 1,126.4 |
Due within one to three years | 289.1 |  |  | — |
Total | $ | 1,318.7 |  |  | $ | 1,126.4 |
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis | The following table presents the fair value of our financial assets measured at fair value on a recurring basis (in millions):
| September 30, 2025 |  | December 31, 2024
| Aggregate Fair Value |  | Quoted Prices in Active Markets For Identical Assets |  | Significant Other Observable Remaining Inputs |  | Significant Other Unobservable Remaining Inputs |  | Aggregate Fair Value |  | Quoted Prices in Active Markets For Identical Assets |  | Significant Other Observable Remaining Inputs |  | Significant Other Unobservable Remaining Inputs
|  |  | (Level 1) |  | (Level 2) |  | (Level 3) |  |  |  | (Level 1) |  | (Level 2) |  | (Level 3)
Cash equivalents: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Money market funds | $ | 170.5 |  |  | $ | 170.5 |  |  | $ | — |  |  | $ | — |  |  | $ | 296.1 |  |  | $ | 296.1 |  |  | $ | — |  |  | $ | — |
Commercial paper | 34.0 |  |  | — |  |  | 34.0 |  |  | — |  |  | 59.7 |  |  | — |  |  | 59.7 |  |  | — |
Certificates of deposit and term deposits | 4.5 |  |  | — |  |  | 4.5 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Total cash equivalents | 209.0 |  |  | 170.5 |  |  | 38.5 |  |  | — |  |  | 355.8 |  |  | 296.1 |  |  | 59.7 |  |  | — |
Short-term investments: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. government and agency securities | 437.1 |  |  | 437.1 |  |  | — |  |  | — |  |  | 469.5 |  |  | 464.5 |  |  | 5.0 |  |  | — |
Commercial paper | 370.5 |  |  | — |  |  | 370.5 |  |  | — |  |  | 428.7 |  |  | — |  |  | 428.7 |  |  | — |
Corporate debt securities | 119.7 |  |  | — |  |  | 119.7 |  |  | — |  |  | 166.4 |  |  | — |  |  | 166.4 |  |  | — |
Certificates of deposit and term deposits | 102.3 |  |  | — |  |  | 102.3 |  |  | — |  |  | 61.8 |  |  | — |  |  | 61.8 |  |  | — |
Marketable equity securities | 98.1 |  |  | 98.1 |  |  | — |  |  | — |  |  | 64.2 |  |  | 64.2 |  |  | — |  |  | — |
Total short-term investments | 1,127.7 |  |  | 535.2 |  |  | 592.5 |  |  | — |  |  | 1,190.6 |  |  | 528.7 |  |  | 661.9 |  |  | — |
Long-term investments: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. government and agency securities | 123.4 |  |  | 113.3 |  |  | 10.1 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Corporate debt securities | 165.7 |  |  | — |  |  | 165.7 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Total long-term investments | 289.1 |  |  | 113.3 |  |  | 175.8 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Total | $ | 1,625.8 |  |  | $ | 819.0 |  |  | $ | 806.8 |  |  | $ | — |  |  | $ | 1,546.4 |  |  | $ | 824.8 |  |  | $ | 721.6 |  |  | $ | — |

X
- Definition Financial Instruments and Fair Value [Abstract] + References No definition available. + Details
Name: | ftnt_FinancialInstrumentsAndFairValueAbstract
Namespace Prefix: | ftnt_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Schedule of Amortized Costs, Unrealized Gains and Losses, and Fair Value of Available For Sale Securities And Equity Securities + References No definition available. + Details
Name: | ftnt_ScheduleOfAmortizedCostsUnrealizedGainsAndLossesAndFairValueOfAvailableForSaleSecuritiesAndEquitySecuritiesTableTextBlock
Namespace Prefix: | ftnt_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479081/326-30-55-8 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-6 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-4 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionFairValueTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of maturities of an entity's investments as well as any other information pertinent to the investments. + References No definition available. + Details
Name: | us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
Name: | us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration