Policyholders' Liabilities - Policyholders' Account Balance Reconciliation to Policyholders' Account Balances' Liability (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Policyholder Account Balance [Line Items]
Annuities	$ 145,838	$ 133,216	$ 129,909
Premiums paid in advance	32,420	$ 32,446	35,453
Supplemental Contracts Without Life Contingencies
Policyholder Account Balance [Line Items]
Annuities	57,030		41,804
Fixed Annuity
Policyholder Account Balance [Line Items]
Annuities	87,327		86,581
Unearned Revenue Reserve
Policyholder Account Balance [Line Items]
Annuities	1,481		1,524
Premiums Paid In Advance
Policyholder Account Balance [Line Items]
Premiums paid in advance	30,600		33,312
Other
Policyholder Account Balance [Line Items]
Premiums paid in advance	$ 1,820		$ 2,141