Policyholders' Liabilities - Policyholder Account Balance (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Policyholder Account Balance [Roll Forward]
Policyholder Account Balance, Ending Balance	$ 211,715	$ 199,786
Supplemental Contracts Without Life Contingencies
Policyholder Account Balance [Roll Forward]
Policyholder Account Balance, Beginning Balance	44,569	32,995
Policyholder Account Balance, Issuance	5,721	4,788
Policyholder Account Balance, Premium Received	27	18
Policyholder Account Balance, Interest Credited	474	343
Policyholder Account Balance, Surrender and Withdrawal	0	0
Policyholder Account Balance, Benefit Payment	2,121	2,309
Policyholder Account Balance, Ending Balance	$ 48,670	$ 35,835
Weighted-average crediting rates	3.96%	4.05%
Policyholder Account Balance, Cash Surrender Value	$ 48,670	$ 35,835
Fixed Annuity
Policyholder Account Balance [Roll Forward]
Policyholder Account Balance, Beginning Balance	87,134	86,807
Policyholder Account Balance, Issuance	594	763
Policyholder Account Balance, Premium Received	985	1,170
Policyholder Account Balance, Interest Credited	663	668
Policyholder Account Balance, Surrender and Withdrawal	2,572	2,247
Policyholder Account Balance, Benefit Payment	0	0
Policyholder Account Balance, Ending Balance	$ 86,804	$ 87,161
Weighted-average crediting rates	3.57%	3.57%
Policyholder Account Balance, Cash Surrender Value	$ 86,804	$ 87,161
Dividend Accumulations
Policyholder Account Balance [Roll Forward]
Policyholder Account Balance, Beginning Balance	44,960	41,663
Policyholder Account Balance, Issuance	138	148
Policyholder Account Balance, Premium Received	1,358	1,384
Policyholder Account Balance, Interest Credited	472	324
Policyholder Account Balance, Surrender and Withdrawal	1,168	851
Policyholder Account Balance, Benefit Payment	0	0
Policyholder Account Balance, Ending Balance	$ 45,760	$ 42,668
Weighted-average crediting rates	3.28%	3.05%
Policyholder Account Balance, Cash Surrender Value	$ 45,760	$ 42,668
Premiums Paid In Advance
Policyholder Account Balance [Roll Forward]
Policyholder Account Balance, Beginning Balance	31,039	34,603
Policyholder Account Balance, Issuance	806	905
Policyholder Account Balance, Premium Received	194	145
Policyholder Account Balance, Interest Credited	431	226
Policyholder Account Balance, Surrender and Withdrawal	1,989	1,757
Policyholder Account Balance, Benefit Payment	0	0
Policyholder Account Balance, Ending Balance	$ 30,481	$ 34,122
Weighted-average crediting rates	2.93%	2.98%
Policyholder Account Balance, Cash Surrender Value	$ 30,481	$ 34,122