The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before the balance sheet date, whether or not reported to the insurer at that date.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Liability for Unpaid Claims - Schedule of Reconciliation of Policy Claims and Other Benefits Payable (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Policy claims and other benefits payable:
Policy claims and other benefits payable	$ 520,094	$ 514,875
Life insurance
Policy claims and other benefits payable:
Policy claims and other benefits payable	319,049	320,066
Health insurance
Policy claims and other benefits payable:
Policy claims and other benefits payable	$ 201,045	$ 194,809	$ 184,286