Investments (Mortgage Loans by Credit Quality Indicator) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 8,493	$ 7,459
Construction Loan	$ 58	$ 46
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	$ 4,625	$ 4,017
Construction Loan	$ 13	$ 46
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	54.50%	53.90%
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	$ 2,493	$ 2,145
Construction Loan	$ 45	$ 0
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	29.40%	28.80%
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	$ 875	$ 929
Construction Loan	$ 0	$ 0
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	10.20%	12.40%
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	$ 500	$ 368
Construction Loan	$ 0	$ 0
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	5.90%	4.90%
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	$ 7,551	$ 6,660
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	4,327	3,672
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	2,148	1,947
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	737	843
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	339	198
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	596	548
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	202	272
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	237	154
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	102	52
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	55	70
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	288	205
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	83	27
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	63	44
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	36	34
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	$ 106	$ 100

The amount represents the total percentage of each property type in comparison to the total of mortgage loans whose balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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This element represents the carrying value of a short-term real estate loan to finance building costs. The funds are disbursed as needed or in accordance with a prearranged plan; generally, a portion of the funds is disbursed at inception and the remainder as construction progresses. The money is repaid on completion of the project, usually from the proceeds of a mortgage loan. The rate is normally higher than the prime rate, and there is usually an origination fee. The effective yield on these loans tends to be high, and the lender has a security interest in the real property. Note that there are separate concepts for the current and noncurrent portions of long-term construction loans.

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