Investments (Residential Mortgage Loans By Year Of Origination) (Details) - Residential [Member] - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 95
2019	438
2018	214
Total	747	$ 735
Performing [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	95
2019	402
2018	206
Total	703	718
Nonperforming [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2019	36
2018	8
Total	$ 44	$ 17

Amount of financing receivable originated in current fiscal year.

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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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