Equity (Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ 347,435
Income tax benefit (expense)	510,840	$ 52,374	$ (70,806)
Ending balance	(1,581,300)	347,435
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(11,274)	(7,797)	(7,917)
Change in OCI before reclassifications	(9,337)	(3,891)	599
Amounts reclassified from AOCI	0	0	0
Income tax benefit (expense)	604	414	(479)
Ending balance	(20,007)	(11,274)	(7,797)
Net Unrealized Investment Gains (Losses)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	358,709	553,925	289,359
Change in OCI before reclassifications	(2,425,810)	(222,182)	327,819
Amounts reclassified from AOCI	(4,428)	(24,994)	7,074
Income tax benefit (expense)	510,236	51,960	(70,327)
Ending balance	(1,561,293)	358,709	553,925
Total Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	347,435	546,128	281,442
Change in OCI before reclassifications	(2,435,147)	(226,073)	328,418
Amounts reclassified from AOCI	(4,428)	(24,994)	7,074
Income tax benefit (expense)	510,840	52,374	(70,806)
Ending balance	(1,581,300)	347,435	546,128
Cash flow hedges | Net Unrealized Investment Gains (Losses)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	40,000	(8,000)
Ending balance	$ 139,000	$ 40,000	$ (8,000)