Investments (Residential Mortgage Loans By Year Of Origination) (Details) - Residential [Member] - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 73
2019	472
2018	229
Total	774	$ 735
Performing [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	73
2019	454
2018	223
Total	750	718
Nonperforming [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2019	18
2018	6
Total	$ 24	$ 17

Amount of financing receivable originated in current fiscal year.

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-Publisher FASB
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Amount of financing receivable originated in fiscal year prior to latest fiscal year.

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Amount, before allowance for credit loss, of financing receivable.

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