Investments (Credit Quality Indicators For Residential Mortgage Loans) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Mortgage Loans Credit Quality [Line Items]
Mortgage loans on real estate, ACL	$ 202	$ 273	$ 2
Residential [Member]
Mortgage Loans Credit Quality [Line Items]
Amortized Cost	$ 730		$ 735
Percent of total	100.00%		100.00%
Mortgage loans on real estate, ACL	$ 30	$ 37	$ 2
Performing [Member] \| Residential [Member]
Mortgage Loans Credit Quality [Line Items]
Amortized Cost	$ 648		$ 718
Percent of total	88.80%		97.70%
Nonperforming [Member] \| Residential [Member]
Mortgage Loans Credit Quality [Line Items]
Amortized Cost	$ 82		$ 17
Percent of total	11.20%		2.30%

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.

No definition available.

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- Definition

Reflects the percentage derived from dividing mortgage loans with a specified loan-to-value ratio by total principal amount of mortgage loans.

+ References

No definition available.

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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