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Investments (Mortgage Loans by Maturity Date) (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Document Period End Date | Mar. 31, 2021 |
Financing Receivable, before Allowance for Credit Loss | $ 6,058 | $ 5,861
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 | $ 2,478 | $ 2,276
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total | 40.90% | 38.80%
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 | $ 2,674 | $ 2,768
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total | 44.10% | 47.30%
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 | $ 906 | $ 817
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total | 15.00% | 13.90%

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- Definition 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. + References No definition available. + Details
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