Deferred Transaction Costs (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred policy acquisition costs, beginning of year	$ 382,080	$ 723,972	$ 841,704
Deferrals	77,306	69,857	64,824
Amortization, excluding unlocking, net of interest	(84,349)	(107,917)	(117,748)
Unlocking	36,510	(22,358)	8,643
Adjustments related to unrealized gains (losses)	158,292	(261,186)	(73,451)
Reinsurance	0	(20,288)	0
Deferred policy acquisition costs, end of year	569,839	382,080	723,972
Movement in Deferred Sales Inducements [Roll Forward]
Deferred sales inducements, beginning of year	43,845	104,359	133,714
Deferrals	18,118	10,344	3,160
Amortization, excluding unlocking, net of interest	(14,755)	(18,363)	(19,714)
Unlocking	993	(4,445)	(641)
Adjustments related to unrealized gains (losses)	29,935	(43,557)	(12,160)
Reinsurance	0	(4,493)	0
Deferred sales inducements, end of year	78,136	43,845	104,359
Movement Analysis Of Value Of Business Acquired [Roll Forward]
VOBA, beginning of year	162,968	138,071	0
Business acquired	0	0	145,768
Other increase	0	35,125	0
Amortization, excluding unlocking	(8,469)	(10,228)	(7,697)
VOBA, end of year	154,499	162,968	138,071
Present Value of Future Insurance Profits, Amortization Expense [Abstract]
2022	8,075
2023	7,757
2024	7,464
2025	7,289
2026	7,162
Cost of Reinsurance [Abstract]
Balance, beginning of year	102,840	0	0
Additions	0	102,840	0
Amortization	(13,154)	0	0
Balance as of end of year	$ 89,686	$ 102,840	$ 0

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