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Investments (Mortgage Loans by Maturity Date) (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Dec. 31, 2019
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Document Period End Date | Mar. 31, 2020 |
Financing Receivable, before Allowance for Credit Loss | $ 6,063 | $ 5,727
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 | $ 2,011 | $ 1,841
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total | 33.20% | 32.20%
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 | $ 3,107 | $ 2,944
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total | 51.20% | 51.40%
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 | $ 945 | $ 942
Mortgage Loans On Real Estate Commercial And Consumer Net Percentage Of Total | 15.60% | 16.40%

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- Definition The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD. + References No definition available. + Details
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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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- Definition Amount, before allowance for credit loss, of financing receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919230-210447 + Details
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