Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 107,172	$ (111,033)
Other comprehensive income (loss) before income taxes:
Net change in unrealized gain or loss on securities available for sale and cash flow hedges	(145,490)	165,297
Reclassification of net gain or loss realized and included in earnings	286	368
Amortization of unrealized net loss or gain on securities transferred to held to maturity	(56)	(195)
Other comprehensive income (loss) before income taxes	(145,260)	165,470
Income tax expense (benefit)	(33,748)	37,480
Other comprehensive income (loss) net of income taxes	(111,512)	127,990
Comprehensive income (loss)	$ (4,340)	$ 16,957