Investments - Commercial Mortgage Loan Participations, Allowance for Credit Loss (Details) - Commercial mortgage loan participations $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($) loan	Dec. 31, 2021 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Number of loans \| loan	22
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses beginning balance	$ 827	$ 3,505
Provision (reversal) for credit losses	962	(2,678)
Allowance for credit losses ending balance	$ 1,789	$ 827

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