Policy Liabilities - Schedule of Policyholder Account Balance (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Interest Sensitive Life
Policyholder Account Balance [Roll Forward]
Beginning Balance	$ 732,948	$ 739,105
Issuances	0	0
Premiums received	5,624	6,030
Policy charges	(3,111)	(3,319)
Surrenders and withdrawals	(6,309)	(5,384)
Benefit payments	(9,140)	(7,844)
Interest credited	7,016	7,135
Other	2,693	2,177
Ending Balance	$ 729,721	$ 737,900
Weighted-average credit rate	3.89%	3.92%
Net amount at risk	$ 1,740,325	$ 1,847,128
Cash surrender value	669,721	676,247
Deferred Annuity
Policyholder Account Balance [Roll Forward]
Beginning Balance	773,039	954,318
Issuances	198	202
Premiums received	3,573	4,776
Policy charges	0	0
Surrenders and withdrawals	(31,563)	(43,533)
Benefit payments	(12,771)	(15,784)
Interest credited	6,243	7,560
Other	300	258
Ending Balance	$ 739,019	$ 907,797
Weighted-average credit rate	3.34%	3.29%
Cash surrender value	$ 739,019	$ 907,797
Other Policy-holders' Funds
Policyholder Account Balance [Roll Forward]
Beginning Balance	236,958	123,236
Issuances	0	0
Premiums received	166,700	21,662
Policy charges	0	0
Surrenders and withdrawals	(3,517)	(3,303)
Benefit payments	0	0
Interest credited	3,521	1,238
Other	(2,393)	(147)
Ending Balance	$ 401,269	$ 142,686
Weighted-average credit rate	4.49%	3.78%
Cash surrender value	$ 401,269	$ 142,686