Investments - Repurchase Agreements (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Investments [Abstract]
Securities Sold under Agreements to Repurchase, Gross	$ 663	$ 262
Securities Sold Under Agreements to Repurchase, Collateral, Obligation to Return	679	267
Securities Sold under Agreements to Repurchase, Fair Value of Collateral	$ 44	$ 28

Securities Sold Under Agreements to Repurchase, Collateral, Obligation to Return

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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- Definition

Fair value of securities pledged as collateral against securities sold under agreement to repurchase.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226013-175313

+ Details

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Period Type:	instant

- Definition

Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226000-175313

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

+ Details

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