Liability For Future Policy Benefits (Future Policy Benefits) (Details) - USD ($) $ in Thousands	Mar. 31, 2023		Dec. 31, 2022		Mar. 31, 2022	Dec. 31, 2021
Insurance [Abstract]
Future policy benefits	$ 21,759,543	[1]	$ 20,829,033	[1]	$ 20,107,861
Liability for Future Policy Benefit, Activity [Line Items]
Balance prior to transition	13,252,702		12,664,445		11,121,489	$ 11,660,527
Balance, EOP, post-flooring	7,428,204				7,845,870
Other Future Policy Benefits reserves	1,059,906				1,124,291
Total Future policy Benefits	21,759,543	[1]	$ 20,829,033	[1]	20,107,861
Total
Liability for Future Policy Benefit, Activity [Line Items]
Benefit reserves, end of period, post-flooring	7,428,204				7,845,870
Balance prior to transition	13,252,702				11,121,489
Deferred profit liability, end of period, post-flooring	18,731				16,211
Balance, EOP, post-flooring	$ 20,699,637				$ 18,983,570

[1] Prior period amounts adjusted for the implementation of ASU 2018-12: Targeted Improvements to the Accounting for Long-Duration Contracts.