Policyholders' Liabilities (Additional Insurance Reserves) (Details) - Variable/Universal Life - Policyholder Contract Deposit - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance, beginning of period	$ 3,741,426	$ 3,067,335
Unearned revenue	211,542	200,262
Amortization Expense	(44,470)	(32,752)
Other adjustments	(1)	(90)
Balance, end of period	3,908,497	3,234,755
Less: Reinsurance recoverables	1,762,417	1,583,054
Unearned revenue reserve net of reinsurance recoverables	$ 2,146,080	$ 1,651,701