Reinsurance (Reinsurance amounts included in the Statement of Operations and Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Premiums:
Direct	$ 471,343	$ 486,008	$ 945,271	$ 972,885
Assumed	(9,474)	41	(8,077)	84
Ceded	(404,448)	(441,187)	(805,528)	(883,702)
Net premiums	57,421	44,862	131,666	89,267
Policy charges and fee income:
Direct	900,644	893,456	1,802,968	1,803,345
Assumed	161,372	146,537	312,193	286,650
Ceded	(436,204)	(859,793)	(1,297,787)	(1,757,930)
Net policy charges and fee income	625,812	180,200	817,374	332,065
Net investment income:
Direct	195,480	96,905	390,991	197,300
Assumed	365	371	818	730
Ceded	(3,717)	(1,976)	(20,381)	(3,863)
Net investment income	192,128	95,300	371,428	194,167
Asset administration fees:
Direct	88,655	98,823	186,112	195,437
Assumed	0	0	0	0
Ceded	(16,865)	(92,547)	(35,090)	(182,950)
Net asset administration fees	71,790	6,276	151,022	12,487
Other income (loss):
Direct	(325,563)	24,577	(674,251)	41,677
Assumed	(2,548)	13	(2,509)	(60)
Ceded	(60)	41	(438)	106
Amortization of reinsurance income	16,155	999	37,578	2,151
Net Other income (loss)	(312,016)	25,630	(639,620)	43,874
Realized investment gains (losses), net:
Direct	1,148,607	(1,655,473)	2,355,755	4,502,274
Assumed	(281,646)	0	(485,630)	0
Ceded	(152,252)	1,532,971	(371,309)	(4,548,168)
Realized investment gains (losses), net	714,709	(122,502)	1,498,816	(45,894)
Policyholders’ benefits (including change in reserves):
Direct	1,421,515	801,694	2,326,652	1,799,518
Assumed	761,610	225,704	1,000,277	417,509
Ceded	(2,025,019)	(949,322)	(2,949,059)	(2,045,038)
Net policyholders’ benefits (including change in reserves)	158,106	78,076	377,870	171,989
Interest credited to policyholders’ account balances:
Direct	202,814	100,790	404,840	280,225
Assumed	29,601	32,132	102,103	65,118
Ceded	(109,471)	(85,522)	(220,473)	(241,773)
Net interest credited to policyholders’ account balances	122,944	47,400	286,470	103,570
Reinsurance expense allowances and general and administrative expenses, net of capitalization and amortization	(80,230)	(292,845)	(216,082)	(761,280)
Unaffiliated activity
Premiums:
Assumed	(13,000)	100	(13,000)	100
Ceded	(9,000)	(7,000)	(16,000)	(14,000)
Policy charges and fee income:
Assumed	11,000	0	11,000	0
Ceded	(20,000)	(16,000)	(38,000)	(30,000)
Net investment income:
Ceded	9,000	0	4,000	0
Other income (loss):
Assumed	(3,000)	0	(3,000)	0
Realized investment gains (losses), net:
Assumed	(282,000)	0	(282,000)	0
Ceded	(9,000)	31,000	(14,000)	(110,000)
Policyholders’ benefits (including change in reserves):
Assumed	1,000	200	1,000	300
Ceded	(18,000)	(50,000)	(38,000)	(131,000)
Interest credited to policyholders’ account balances:
Assumed	$ (3,000)	$ 0	$ (3,000)	$ 0