Deferred Policy Acquisition Costs, Deferred Reinsurance Losses, Deferred Reinsurance Gains And Deferred Sales Inducements (Balance of and Changes in DAC) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023		Mar. 31, 2022
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred Policy Acquisition Cost, Beginning Balance	$ 6,930,425	[1]	$ 7,029,307
Capitalization	246,738		246,389
Amortization expense	(137,546)		(125,075)
Other adjustments	52		(541,408)
Balance, end of period	7,039,669	[1]	6,609,213
Fixed Annuities
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred Policy Acquisition Cost, Beginning Balance	102,250		84,479
Capitalization	22,902		746
Amortization expense	(4,474)		(3,191)
Other adjustments	0		0
Balance, end of period	120,678		82,034
Variable Annuities
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred Policy Acquisition Cost, Beginning Balance	3,736,456		3,806,733
Capitalization	56,875		77,128
Amortization expense	(87,864)		(84,575)
Other adjustments	0		0
Balance, end of period	3,705,467		3,799,286
Term Life
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred Policy Acquisition Cost, Beginning Balance	648,836		577,084
Capitalization	33,006		33,626
Amortization expense	(15,304)		(11,432)
Other adjustments	0		0
Balance, end of period	666,538		599,278
Variable/Universal Life
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred Policy Acquisition Cost, Beginning Balance	2,442,883		2,561,011
Capitalization	133,955		134,889
Amortization expense	(29,904)		(25,877)
Other adjustments	52		(541,408)
Balance, end of period	$ 2,546,986		$ 2,128,615

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