Investments (Mortgage Loans by Credit Quality Indicator) (Details) - USD ($) $ in Millions	Sep. 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	$ 7,320	$ 6,653
Construction Loan	$ 45	$ 18
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	100.00%	100.00%
Mortgage Loans By Credit Quality Indicator Range One [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 4,346	$ 3,755
Construction Loan	$ 45	$ 18
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	59.30%	56.40%
Mortgage Loans By Credit Quality Indicator Range Two [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 2,112	$ 2,084
Construction Loan	$ 0	$ 0
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	28.90%	31.30%
Mortgage Loans By Credit Quality Indicator Range Three [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 586	$ 615
Construction Loan	$ 0	$ 0
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	8.00%	9.30%
Mortgage Loans By Credit Quality Indicator Range Four [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 276	$ 199
Construction Loan	$ 0	$ 0
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	3.80%	3.00%
Debt Service Coverage Ratio Range One [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 6,499	$ 5,916
Debt Service Coverage Ratio Range One [Member] | Mortgage Loans By Credit Quality Indicator Range One [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	3,947	3,466
Debt Service Coverage Ratio Range One [Member] | Mortgage Loans By Credit Quality Indicator Range Two [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	1,929	1,894
Debt Service Coverage Ratio Range One [Member] | Mortgage Loans By Credit Quality Indicator Range Three [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	518	475
Debt Service Coverage Ratio Range One [Member] | Mortgage Loans By Credit Quality Indicator Range Four [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	105	81
Debt Service Coverage Ratio Range Two [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	533	383
Debt Service Coverage Ratio Range Two [Member] | Mortgage Loans By Credit Quality Indicator Range One [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	301	215
Debt Service Coverage Ratio Range Two [Member] | Mortgage Loans By Credit Quality Indicator Range Two [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	154	119
Debt Service Coverage Ratio Range Two [Member] | Mortgage Loans By Credit Quality Indicator Range Three [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	35	49
Debt Service Coverage Ratio Range Two [Member] | Mortgage Loans By Credit Quality Indicator Range Four [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	43	0
Debt Service Coverage Ratio Range Three [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	243	336
Debt Service Coverage Ratio Range Three [Member] | Mortgage Loans By Credit Quality Indicator Range One [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	53	56
Debt Service Coverage Ratio Range Three [Member] | Mortgage Loans By Credit Quality Indicator Range Two [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	29	71
Debt Service Coverage Ratio Range Three [Member] | Mortgage Loans By Credit Quality Indicator Range Three [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	33	91
Debt Service Coverage Ratio Range Three [Member] | Mortgage Loans By Credit Quality Indicator Range Four [Member]
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 128	$ 118