Investments - Schedule of Change in Net Unrealized Gains (Losses) on Available-for-Sale Securities Reported in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
AOCI, Debt Securities, Available-for-Sale, Adjustment, After Tax [Roll Forward]
Beginning balance	$ (1,987)	$ (3,156)
Unrealized gains (losses) arising during the period:
Unrealized gains (losses) on fixed maturity securities	(730)	649
Adjustments to policyholder contract balances	11	(10)
(Provision) benefit for income taxes	153	(136)
Change in unrealized gains (losses) on investment securities	(566)	503
Reclassification adjustments to net investment (gains) losses	17	3
Change in net unrealized investment gains (losses)	(549)	506
Less: change in net unrealized investment gains (losses) attributable to noncontrolling interests	(10)	10
Ending balance	(2,526)	(2,660)
Reclassification adjustments to net investment (gains) losses, taxes	$ (4)	$ (1)

AOCI, Debt Securities, Available-for-Sale, Adjustment, After Tax

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Includes amounts related to other than temporary impairment (OTTI) loss.

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Other comprehensive income unrealized holding gain loss on policyholder contract balances arising during period before tax.

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Amount, after tax, of accumulated unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, after tax and reclassification adjustment, of gain (loss) in value of unsold investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), attributable to noncontrolling interest.

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Amount, after tax and before adjustment, of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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Amount, before adjustment, of tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount, before tax and adjustment, of unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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