Investments - Summary of Debt Securities with a Decline in Fair Value (Details) $ in Millions |
Jun. 30, 2026
USD ($)
position
|
Dec. 31, 2025
USD ($)
position
|
|---|---|---|
| Total | ||
| Fair Value | $ 4,858 | $ 3,733 |
| Total Amortized Cost | 5,259 | 4,100 |
| Unrealized Depreciation | $ (401) | $ (367) |
| Number of Issues | position | 1,882 | 1,273 |
| Investment grade | ||
| One year or less | ||
| Fair Value | $ 1,902 | $ 384 |
| Amortized Cost | 1,925 | 386 |
| Unrealized Depreciation | $ (23) | $ (2) |
| Number of Issues | position | 640 | 149 |
| More than one year | ||
| Fair Value | $ 2,637 | $ 3,044 |
| Amortized Cost | 2,998 | 3,382 |
| Unrealized Depreciation | $ (361) | $ (338) |
| Number of Issues | position | 703 | 799 |
| Below investment grade | ||
| One year or less | ||
| Fair Value | $ 214 | $ 120 |
| Amortized Cost | 219 | 125 |
| Unrealized Depreciation | $ (5) | $ (5) |
| Number of Issues | position | 472 | 239 |
| More than one year | ||
| Fair Value | $ 105 | $ 185 |
| Amortized Cost | 117 | 207 |
| Unrealized Depreciation | $ (12) | $ (22) |
| Number of Issues | position | 67 | 86 |
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- Definition Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months Or Longer No definition available.
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- Definition Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, 12 Months Or Longer, Amortized Cost No definition available.
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- Definition Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Amortized Cost No definition available.
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- Definition Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less Than 12 Months No definition available.
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- Definition Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, Less Than 12 Months, Amortized Cost No definition available.
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- Definition Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Total No definition available.
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset. Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without an allowance for credit loss. Includes beneficial interest in securitized financial asset. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount 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. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of accumulated unrealized loss on 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. Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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- Definition Number of investments in debt securities 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. Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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