Liability For Future Policy Benefits (Future Policy Benefits) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022		Jun. 30, 2022	Dec. 31, 2021
Insurance [Abstract]
Benefit reserves, end of period, post-flooring	$ 7,365,740			$ 7,480,875
Deferred profit liability, end of period, post-flooring	14,502			16,632
Additional insurance reserves, including amounts in AOCI, end of period, post-flooring	13,488,863	$ 12,664,445		12,493,593	$ 11,660,527
Subtotal of amounts disclosed above	20,869,105			19,991,100
Other Future Policy Benefits reserves	1,108,889			1,035,166
Total Future policy Benefits	$ 21,977,994	$ 20,829,033	[1]	$ 21,026,266

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