Business and Basis of Presentation (Summary of Adoption of New Guidance on Consolidated Statement of Cash Flows) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022		Dec. 31, 2021
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income (Loss)	$ 461,691	$ (766,705)	[1]	$ (1,394,701)	[1]
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Policy charges and fee income	69,986	131,936	[1]	165,675	[1]
Interest credited to policyholders’ account balances	655,445	445,215	[1]	(151,389)	[1]
Realized investment gains (losses), net	1,083,660	(336,382)	[1]	386,894	[2]
Change in value of market risk benefits, net of related hedging (gains) losses	94,368	700,581	[2]	4,222,530	[1]
Change in:
Future policy benefits and other insurance liabilities	2,241,530	3,743,780	[1]	1,831,520	[1]
Reinsurance recoverables	(639,002)	(2,254,290)	[1]	(1,134,683)	[1]
Deferred policy acquisition costs	(560,471)	(442,303)	[1]	(4,067,946)	[1]
Income taxes	(37,886)	(334,769)	[1]	(842,107)	[1]
Other, net	(395,372)	1,567,947	[1]	1,376,588	[1]
Net Cash Provided by (Used in) Operating Activities	$ 2,459,895	1,824,964		(883,941)
As Originally Reported
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income (Loss)		341,749		(2,209,730)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Policy charges and fee income		(78,754)		(21,763)
Interest credited to policyholders’ account balances		517,488		(114,585)
Realized investment gains (losses), net		(1,041,435)		5,295,406
Change in value of market risk benefits, net of related hedging (gains) losses		0		0
Change in:
Future policy benefits and other insurance liabilities		2,407,887		2,080,967
Reinsurance recoverables		(1,181,692)		(1,304,306)
Deferred policy acquisition costs		(105,194)		(3,926,121)
Income taxes		(40,095)		(1,082,459)
Other, net		1,635,056		1,674,972
Net Cash Provided by (Used in) Operating Activities		1,824,964		(883,941)
Effect of Change
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income (Loss)		(1,108,454)		815,029
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Policy charges and fee income		210,690		187,438
Interest credited to policyholders’ account balances		(72,273)		(36,804)
Realized investment gains (losses), net		705,053		(4,908,512)
Change in value of market risk benefits, net of related hedging (gains) losses		700,581		4,222,530
Change in:
Future policy benefits and other insurance liabilities		1,335,893		(249,447)
Reinsurance recoverables		(1,072,598)		169,623
Deferred policy acquisition costs		(337,109)		(141,825)
Income taxes		(294,674)		240,352
Other, net		(67,109)		(298,384)
Net Cash Provided by (Used in) Operating Activities		$ 0		$ 0

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

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