Certain Long-Duration Contracts with Guarantees Liabilities for Guarantee Benefits (Details) - Annuity Contracts - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Beginning balance	$ 18,127,859	$ 12,526,898	$ 8,992,937
Incurred guarantee benefits	(4,932,855)	5,637,113	3,562,205
Paid guarantee benefits	(42,808)	(73,138)	(54,895)
Change in unrealized investment gains and losses	(38,282)	36,986	26,651
Other	(8,832,528)
Ending balance	4,281,386	18,127,859	12,526,898
GMDB
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Beginning balance	788,455	681,504	638,403
Incurred guarantee benefits	(4,690)	139,032	68,142
Paid guarantee benefits	(42,808)	(68,693)	(51,418)
Change in unrealized investment gains and losses	(37,925)	36,612	26,377
Other	(486,734)
Ending balance	216,298	788,455	681,504
GMAB/GMWB/ GMIWB
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Beginning balance	17,314,004	11,822,998	8,332,474
Incurred guarantee benefits	(4,923,835)	5,491,006	3,490,524
Paid guarantee benefits	0	0	0
Change in unrealized investment gains and losses	0	0	0
Other	(8,329,954)
Ending balance	4,060,215	17,314,004	11,822,998
GMIB
Movement in Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross [Roll Forward]
Beginning balance	25,400	22,396	22,060
Incurred guarantee benefits	(4,330)	7,075	3,539
Paid guarantee benefits	0	(4,445)	(3,477)
Change in unrealized investment gains and losses	(357)	374	274
Other	(15,840)
Ending balance	$ 4,873	$ 25,400	$ 22,396