Reinsurance (Reinsurance amounts included in the Statement of Operations and Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Premiums:
Direct	$ 473,928	$ 486,877
Assumed	1,397	43
Ceded	(401,080)	(442,515)
Net premiums	74,245	44,405
Policy charges and fee income:
Direct	902,324	909,889
Assumed	150,821	140,113
Ceded	(861,583)	(898,137)
Net policy charges and fee income	191,562	151,865
Net investment income:
Direct	195,511	100,395
Assumed	453	359
Ceded	(16,664)	(1,887)
Net investment income	179,300	98,867
Asset administration fees:
Direct	97,457	96,614
Assumed	0	0
Ceded	(18,225)	(90,403)
Net asset administration fees	79,232	6,211
Other income (loss):
Direct	(348,688)	17,100
Assumed	39	(73)
Ceded	(378)	65
Amortization of reinsurance income	21,423	1,152
Net Other income (loss)	(327,604)	18,244
Realized investment gains (losses), net:
Direct	1,260,511	6,157,747
Assumed	(225,262)	0
Ceded	(251,142)	(6,081,139)
Realized investment gains (losses), net	784,107	76,608
Policyholders’ benefits (including change in reserves):
Direct	905,137	997,824
Assumed	238,667	191,805
Ceded	(924,040)	(1,095,716)
Net policyholders’ benefits (including change in reserves)	219,764	93,913
Interest credited to policyholders’ account balances:
Direct	202,026	179,435
Assumed	72,502	32,986
Ceded	(111,002)	(156,251)
Net interest credited to policyholders’ account balances	163,526	56,170
Reinsurance expense allowances and general and administrative expenses, net of capitalization and amortization	(135,852)	(468,435)
Unaffiliated activity
Premiums:
Assumed	0	0
Ceded	(7,000)	(7,000)
Policy charges and fee income:
Ceded	(18,000)	(14,000)
Other income (loss):
Assumed	0	0
Realized investment gains (losses), net:
Ceded	(37,000)	(141,000)
Policyholders’ benefits (including change in reserves):
Assumed	100	100
Ceded	$ (20,000)	$ (81,000)