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Income Taxes - Reconciliation of effective tax rate (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Expected income tax expense (benefit) computed on pre-tax income at weighted average income tax rate	$ 774	$ 424	$ 300
Addition (reduction) in income tax expense (benefit) resulting from:
Sale of subsidiaries/Bargain purchase option		(45)	0
Investment income	(54)	(39)	(14)
Change in tax rate	(65)	12	(1,179)
Share based compensation		(11)	(13)
Tax credits		(5)	(3)
Base eroding tax/Alternative minimum tax		5	9
State taxes, net of U.S. federal tax benefit		4	6
Change in valuation allowance		3	4
Uncertain tax position		3	0
Dividend withholding taxes		3	9
Other		8	8
Income tax expense (benefit)	$ 760	$ 362	$ (873)

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