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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- Definition

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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- Definition

Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Investments (Mortgage Loans by Credit Quality Indicator) (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024	Mar. 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
Construction Loan	$ 50	$ 53
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	99.10%	100.00%
Financial Asset, Equal to or Greater than 90 Days Past Due
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Financing Receivable, before Allowance for Credit Loss	$ 6		$ 23
Mortgage Loans By Credit Quality Indicator Range One [Member] \| 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	4,455	$ 4,255
Construction Loan	$ 4	$ 7
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	47.60%	47.50%
Mortgage Loans By Credit Quality Indicator Range Two [Member] \| 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	$ 2,774	$ 2,579
Construction Loan	$ 46	$ 46
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	29.60%	28.80%
Mortgage Loans By Credit Quality Indicator Range Three [Member] \| 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	$ 1,465	$ 1,430
Construction Loan	$ 0	$ 0
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	15.70%	16.00%
Mortgage Loans By Credit Quality Indicator Range Four [Member] \| 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	$ 665	$ 688
Construction Loan	$ 0	$ 0
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total	7.10%	7.70%
Debt Service Coverage Ratio Range One [Member] \| 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	$ 8,231	$ 8,043
Debt Service Coverage Ratio Range One [Member] \| Mortgage Loans By Credit Quality Indicator Range One [Member] \| 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	4,186	4,017
Debt Service Coverage Ratio Range One [Member] \| Mortgage Loans By Credit Quality Indicator Range Two [Member] \| 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	2,420	2,298
Debt Service Coverage Ratio Range One [Member] \| Mortgage Loans By Credit Quality Indicator Range Three [Member] \| 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	1,179	1,205
Debt Service Coverage Ratio Range One [Member] \| Mortgage Loans By Credit Quality Indicator Range Four [Member] \| 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	446	523
Debt Service Coverage Ratio Range Two [Member] \| 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	653	596
Debt Service Coverage Ratio Range Two [Member] \| Mortgage Loans By Credit Quality Indicator Range One [Member] \| 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	167	189
Debt Service Coverage Ratio Range Two [Member] \| Mortgage Loans By Credit Quality Indicator Range Two [Member] \| 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	232	184
Debt Service Coverage Ratio Range Two [Member] \| Mortgage Loans By Credit Quality Indicator Range Three [Member] \| 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	218	178
Debt Service Coverage Ratio Range Two [Member] \| Mortgage Loans By Credit Quality Indicator Range Four [Member] \| 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	36	45
Debt Service Coverage Ratio Range Three [Member] \| 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	425	260
Debt Service Coverage Ratio Range Three [Member] \| Mortgage Loans By Credit Quality Indicator Range One [Member] \| 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	98	42
Debt Service Coverage Ratio Range Three [Member] \| Mortgage Loans By Credit Quality Indicator Range Two [Member] \| 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	76	51
Debt Service Coverage Ratio Range Three [Member] \| Mortgage Loans By Credit Quality Indicator Range Three [Member] \| 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	68	47
Debt Service Coverage Ratio Range Three [Member] \| Mortgage Loans By Credit Quality Indicator Range Four [Member] \| 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	$ 183	$ 120