Income Taxes Income Taxes - Effect of Income Taxes on Net Income and Stockholders' Equity (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Expense (Benefit) [Roll Forward]
Income tax expense (benefit)	$ (3)	$ 32	$ 5
Net Unrealized Losses On Securities Tax Effect	3	14	12
Valuation Allowances And Reserves Charged To Equity	(3)	(23)	9
Income Tax Effects Allocated Directly to Equity	1	(8)	3
Unrealized Loss on FX Tax Effect	0	0	0
Income Tax Effects Allocated Directly to Equity, Other	$ (1)	$ 24	$ 8