Income Taxes Income Taxes - Effect of Income Taxes on Net Income and Stockholders' Equity (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Expense (Benefit) [Roll Forward]
Income tax expense (benefit)	$ 7	$ 2	$ 18
Net Unrealized Losses On Securities Tax Effect	12	(47)	(3)
Valuation Allowances And Reserves Charged To Equity	(9)	41	(1)
Income Tax Effects Allocated Directly to Equity	2	(6)	(2)
Change in retirement benefits Tax Effect	(1)	0	0
Credit Risk Changes to Fair Value Options Tax Effect	0	0	0
Income Tax Effects Allocated Directly to Equity, Other	$ 9	$ (4)	$ 16