Investments (Credit Quality Indicators For Residential Mortgage Loans) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Mortgage loans on real estate, ACL	$ 201	$ 271	$ 2
Residential [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amortized Cost	$ 730		$ 735
Percentage of total mortgage loans on real estate	100.00%		100.00%
Mortgage loans on real estate, ACL	$ 30	$ 37	$ 2
Residential [Member] \| Performing [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amortized Cost	$ 648		$ 718
Percentage of total mortgage loans on real estate	88.80%		97.70%
Residential [Member] \| Nonperforming [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amortized Cost	$ 82		$ 17
Percentage of total mortgage loans on real estate	11.20%		2.30%

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

No definition available.

+ Details

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Period Type:	instant

- 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
-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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.

+ 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
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-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919230-210447

+ Details

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- Details

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- Details

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- Details

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