Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Income Tax Contingency [Line Items]
Effective income tax rate	13.20%	(32.40%)	12.50%	(6.40%)	117.00%
Income tax expense	$ 130	$ (19)	$ 155	$ (14)
Unrealized Tax Losses, Available-For-Sale Securities
Income Tax Contingency [Line Items]
Increase to valuation allowance	431		538
Tax expense recorded to other comprehensive income	398		503
Income tax expense	33		35
Deferred tax assets valuation allowance	$ 1,024		$ 1,024		$ 486

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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+ Details

- Definition

Amount of tax expense (benefit) allocated to other comprehensive income (loss).

+ References

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+ Details