Reserves for Future Policy Benefits and Claims Payable - Weighted Average Duration, Closed Block Life (Details)	Mar. 31, 2023	Dec. 31, 2022
Closed Block Life
Liability for Future Policy Benefit, Activity [Line Items]
Weighted average duration (years)	7 years 8 months 12 days	8 years 1 month 6 days

Weighted-average duration of present value of total expected payment to policyholder in excess of present value of total expected assessment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Excludes benefit classified as market risk benefit or under provisions of Topic 815 on derivative and hedging.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 6
-Subparagraph (b)(5)
-URI https://asc.fasb.org/extlink&oid=124506351&loc=d3e14931-158439

Name:	us-gaap_AdditionalLiabilityLongDurationInsuranceWeightedAverageDuration
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant