Investments (Mortgage Loans by Maturity Date) (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 9,441	$ 8,952
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	100.00%	100.00%
Commercial Real Estate
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 9,359	$ 8,952
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	99.10%	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		$ 3,984
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	45.00%	44.50%
Due within five years | Commercial Real Estate
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 4,215
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		$ 3,959
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	46.00%	44.20%
Due after five years through ten years | Commercial Real Estate
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 4,301
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		$ 1,009
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	9.00%	11.30%
Due after ten years | Commercial Real Estate
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 843