Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 116,143	$ 52,926	$ 223,880	$ (1,799,021)
Available for sale securities:
Unrealized gains (losses) arising during the period	22,821	4,570	(64,524)	112,331
Income tax (expense) benefit related to unrealized gains (losses)	(5,870)	(1,175)	16,595	(28,892)
Reclassification adjustment for net realized gains in earnings	0	(323)	(4)	(190)
Income tax expense related to realized gains	0	83	1	49
Net change in unrealized gains (losses) for available for sale securities	16,951	3,155	(47,932)	83,298
Junior subordinated debentures, at fair value:
Unrealized (losses) gains arising during the period	(5,996)	(37,450)	(32,558)	41,412
Income tax benefit (expense) related to unrealized gains	1,542	9,632	8,374	(10,651)
Net change in unrealized (losses) gains for junior subordinated debentures, at fair value	(4,454)	(27,818)	(24,184)	30,761
Other comprehensive (loss) income, net of tax	12,497	(24,663)	(72,116)	114,059
Comprehensive income (loss)	$ 128,640	$ 28,263	$ 151,764	$ (1,684,962)