Investments (Concentrations of Credit Risk - Narrative) (Details) - Foreign government - USD ($) $ in Billions	Mar. 31, 2022	Dec. 31, 2021
Japan
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Government and agency fixed maturity securities	$ 30.1	$ 32.7
Republic of Korea
Fair Value, Concentration of Risk, Financial Statement Captions [Line Items]
Government and agency fixed maturity securities	$ 6.5	$ 7.1

This item represents disclosure of all significant concentrations of credit risk or market risk arising from the subject financial instrument (as defined), whether from an individual counterparty or groups of counterparties.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13531-108611

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