CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Cumulative Effect, Period Of Adoption, Adjustment		Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Retained Earnings Cumulative Effect, Period Of Adoption, Adjustment		Treasury Stock	Accumulated Other Comprehensive Income
Beginning balance - Shares at Dec. 31, 2018				(6,000,000)	(50,201,127)					(417)
Beginning balance - Amount at Dec. 31, 2018	$ 2,480,308			$ 150,000	$ 502	$ 967,890	$ 1,361,406			$ (8)	$ 518
Comprehensive income:
Net income	159,513						159,513
Change in unrealized gain (loss) on available-for-sale securities, net of taxes	7,795										7,795
Comprehensive income/(loss)	167,308
Stock-based compensation expense recognized in earnings	5,542					5,542
Preferred stock dividend	(4,875)						(4,875)
Issuance of stock related to stock-based awards - Shares					88,074
Issuance of stock related to stock-based awards - Amount	(1,212)				$ 1	(1,213)
Issuance of common stock related to warrants - shares					8,768
Issuance of common stock related to warrants	0
Ending balance - Amount at Jun. 30, 2019	2,647,071			$ 150,000	$ 503	972,219	1,516,044			$ (8)	8,313
Ending balance - Shares at Jun. 30, 2019				(6,000,000)	(50,297,969)					(417)
Beginning balance - Shares at Mar. 31, 2019				(6,000,000)	(50,264,028)					(417)
Beginning balance - Amount at Mar. 31, 2019	2,560,718			$ 150,000	$ 503	969,079	1,440,669			$ (8)	475
Comprehensive income:
Net income	77,812						77,812
Change in unrealized gain (loss) on available-for-sale securities, net of taxes	7,838										7,838
Comprehensive income/(loss)	85,650
Stock-based compensation expense recognized in earnings	3,119					3,119
Preferred stock dividend	(2,437)						(2,437)
Issuance of stock related to stock-based awards - Shares					33,941
Issuance of stock related to stock-based awards - Amount	21					21
Ending balance - Amount at Jun. 30, 2019	2,647,071			$ 150,000	$ 503	972,219	1,516,044			$ (8)	8,313
Ending balance - Shares at Jun. 30, 2019				(6,000,000)	(50,297,969)					(417)
Beginning balance - Shares at Dec. 31, 2019				(6,000,000)	(50,338,158)					(417)
Beginning balance - Amount at Dec. 31, 2019	2,801,321	$ (7,154)	[1]	$ 150,000	$ 503	978,205	1,663,671	$ (7,154)	[1]	$ (8)	8,950
Comprehensive income:
Net income	(51,003)						(51,003)
Change in unrealized gain (loss) on available-for-sale securities, net of taxes	(8,474)										(8,474)
Comprehensive income/(loss)	(59,477)
Stock-based compensation expense recognized in earnings	6,549					6,549
Preferred stock dividend	(4,875)						(4,875)
Issuance of stock related to stock-based awards - Shares					97,931
Issuance of stock related to stock-based awards - Amount	(1,609)				$ 1	(1,610)
Ending balance - Amount at Jun. 30, 2020	2,734,755			$ 150,000	$ 504	983,144	1,600,639			$ (8)	476
Ending balance - Shares at Jun. 30, 2020				(6,000,000)	(50,436,089)					(417)
Beginning balance - Shares at Mar. 31, 2020				(6,000,000)	(50,408,195)					(417)
Beginning balance - Amount at Mar. 31, 2020	2,772,596	$ 0	[2]	$ 150,000	$ 504	979,939	1,637,392	$ 0	[2]	$ (8)	4,769
Comprehensive income:
Net income	(34,316)						(34,316)
Change in unrealized gain (loss) on available-for-sale securities, net of taxes	(4,293)										(4,293)
Comprehensive income/(loss)	(38,609)
Stock-based compensation expense recognized in earnings	3,322					3,322
Preferred stock dividend	(2,437)						(2,437)
Issuance of stock related to stock-based awards - Shares					27,894
Issuance of stock related to stock-based awards - Amount	(117)					(117)
Ending balance - Amount at Jun. 30, 2020	$ 2,734,755			$ 150,000	$ 504	$ 983,144	$ 1,600,639			$ (8)	$ 476
Ending balance - Shares at Jun. 30, 2020				(6,000,000)	(50,436,089)					(417)

[1] Represents the impact of adopting Accounting Standard Update ("ASU") 2016-13. See Note 1 to the consolidated financial statements for more information.

[2] Represents the impact of adopting Accounting Standard Update ("ASU") 2016-13. See Note 1 to the consolidated financial statements for more information.