Fair Value Measurements (Assets And Liabilities Recorded At Fair Value On A Nonrecurring Basis) (Details) - Nonrecurring - Level 3 - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis [Line Items]
Total assets at fair value	$ 150	$ 70
Commercial borrower \| Domestic loans
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis [Line Items]
Loans	134	$ 70
Commercial borrower \| Commercial mortgage loans \| Domestic loans
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis [Line Items]
Loans	$ 16

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- 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.

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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