Investments - Investments - ACL on Mortgages (Details) - Commercial Loan [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Financing Receivable, Allowance for Credit Loss [Line Items]
Beginning balance	$ (36)	$ (29)
Current period provision	0	2
Financing Receivable, Allowance for Credit Loss	$ (36)	$ (31)

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Name:	us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant