Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 108,066	$ 124,871	$ 331,946	$ (1,674,150)
Available for sale securities:
Unrealized (losses) gains arising during the period	(29,009)	2,996	(93,533)	115,327
Income tax benefit (expense) related to unrealized (losses) gains	7,463	(771)	24,058	(29,663)
Reclassification adjustment for net realized gains in earnings	0	0	(4)	(190)
Income tax expense related to realized gains	0	0	1	49
Net change in unrealized (losses) gains for available for sale securities	(21,546)	2,225	(69,478)	85,523
Junior subordinated debentures, at fair value:
Unrealized (losses) gains arising during the period	(11,946)	(14,555)	(44,504)	26,857
Income tax benefit (expense) related to unrealized gains	3,072	3,744	11,446	(6,907)
Net change in unrealized (losses) gains for junior subordinated debentures, at fair value	(8,874)	(10,811)	(33,058)	19,950
Other comprehensive (loss) income, net of tax	(30,420)	(8,586)	(102,536)	105,473
Comprehensive income (loss)	$ 77,646	$ 116,285	$ 229,410	$ (1,568,677)