Future Policy Benefit Reserves - Weighted Average Interest Rates (Details)	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023
Insurance [Abstract]
Original locked in discount rate	5.22%	5.22%	5.26%
Upper-medium grade fixed income instrument discount rate	5.20%	4.94%	4.92%

Original weighted-average discount rate at contract issue date used to measure liability for future policy benefit.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 29E
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480046/944-40-55-29E

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Subparagraph (b)(6)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480081/944-40-50-6

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant