Investments (Mortgage Loans by Maturity Date) (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 7,109	$ 6,653
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	100.00%	100.00%
Due within five years
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 3,085	$ 2,652
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	43.40%	39.90%
Due after five years through ten years
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 3,058	$ 2,930
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	43.00%	44.00%
Due after ten years
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 966	$ 1,071
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	13.60%	16.10%