Investments (Schedule of Securities Pledged by Contractual Maturity) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Lending	$ 116	$ 114
Total gross secured borrowings	116	114
Corporate Bonds [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Lending	114	114
Foreign Government Bonds [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Lending	2
Overnight and Continuous [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Total gross secured borrowings	116	114
Overnight and Continuous [Member] \| Corporate Bonds [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Lending	114	$ 114
Overnight and Continuous [Member] \| Foreign Government Bonds [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Lending	$ 2

Amount, before effects of master netting arrangements, of financial assets loaned to entities in exchange for collateral and funds outstanding borrowed in the form of a financial asset repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same financial assets at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

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- Definition

Amount, before effects of master netting arrangements, of financial assets loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and financial assets transferred other than securities that qualify as secured borrowings.

+ References

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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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