CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Cumulative Effect of the Change in Accounting Principle	Common Stock	Additional Paid-in Capital	Accumulated Retained Earnings	Accumulated Retained Earnings Cumulative Effect of the Change in Accounting Principle	Accumulated Other Comprehensive Income (Loss)
Balance at beginning of period (in shares) at Dec. 31, 2019			59,506,057
Balance at beginning of period at Dec. 31, 2019	$ 2,012,594	$ (45,625)	$ 586	$ 1,594,434	$ 396,051	$ (45,625)	$ 21,523
Increase (Decrease) in Stockholders' Equity
Net income (loss)	(73,351)				(73,351)
Other comprehensive income (loss)	36,701						36,701
Cash dividends declared	(29,874)				(29,874)
Dividend equivalents declared	0			123	(123)
Share-based compensation expense	4,848			4,848
Issuance of restricted stock, net (in shares)			473,509
Issuance of restricted stock, net	0
Issuance of common stock - acquisition (in shares)			34,407,403
Issuance of common stock - acquisition	749,603		$ 344	749,259
Restricted stock surrendered and canceled (in shares)			(94,306)
Restricted stock surrendered and canceled	(1,273)			(1,273)
Exercise of stock options (in shares)			58,239
Exercise of stock options	1,024			1,024
Balance at end of period (in shares) at Jun. 30, 2020			94,350,902
Balance at end of period at Jun. 30, 2020	2,654,647		$ 930	2,348,415	247,078		58,224
Balance at beginning of period (in shares) at Mar. 31, 2020			59,975,281
Balance at beginning of period at Mar. 31, 2020	2,002,917		$ 586	1,596,680	361,242		44,409
Increase (Decrease) in Stockholders' Equity
Net income (loss)	(99,091)				(99,091)
Other comprehensive income (loss)	13,815						13,815
Cash dividends declared	(14,992)				(14,992)
Dividend equivalents declared	0			81	(81)
Share-based compensation expense	2,539			2,539
Issuance of restricted stock, net (in shares)			23,229
Issuance of restricted stock, net	0
Issuance of common stock - acquisition (in shares)			34,407,403
Issuance of common stock - acquisition	749,603		$ 344	749,259
Restricted stock surrendered and canceled (in shares)			(61,367)
Restricted stock surrendered and canceled	(265)			(265)
Exercise of stock options (in shares)			6,356
Exercise of stock options	121			121
Balance at end of period (in shares) at Jun. 30, 2020			94,350,902
Balance at end of period at Jun. 30, 2020	$ 2,654,647		$ 930	2,348,415	247,078		58,224
Balance at beginning of period (in shares) at Dec. 31, 2020	94,483,136		94,483,136
Balance at beginning of period at Dec. 31, 2020	$ 2,746,649		$ 931	2,354,871	330,555		60,292
Increase (Decrease) in Stockholders' Equity
Net income (loss)	68,668
Other comprehensive income (loss)	(75,481)
Balance at end of period (in shares) at Mar. 31, 2021			94,644,415
Balance at end of period at Mar. 31, 2021	$ 2,703,098		$ 931	2,348,445	368,911		(15,189)
Balance at beginning of period (in shares) at Dec. 31, 2020	94,483,136		94,483,136
Balance at beginning of period at Dec. 31, 2020	$ 2,746,649		$ 931	2,354,871	330,555		60,292
Increase (Decrease) in Stockholders' Equity
Net income (loss)	164,970				164,970
Other comprehensive income (loss)	(33,768)						(33,768)
Repurchase and retirement of common stock (in shares)			(199,674)
Repurchase and retirement of common stock	(6,897)		$ (2)	(4,977)	(1,918)
Cash dividends declared	(59,521)				(59,521)
Dividend equivalents declared	0			234	(234)
Share-based compensation expense	6,562			6,562
Issuance of restricted stock, net (in shares)			435,957
Issuance of restricted stock, net	0		$ 2	(2)
Restricted stock surrendered and canceled (in shares)			(110,027)
Restricted stock surrendered and canceled	(5,308)			(5,308)
Exercise of stock options (in shares)			47,183
Exercise of stock options	$ 732			732
Balance at end of period (in shares) at Jun. 30, 2021	94,656,575		94,656,575
Balance at end of period at Jun. 30, 2021	$ 2,813,419		$ 931	2,352,112	433,852		26,524
Balance at beginning of period (in shares) at Mar. 31, 2021			94,644,415
Balance at beginning of period at Mar. 31, 2021	2,703,098		$ 931	2,348,445	368,911		(15,189)
Increase (Decrease) in Stockholders' Equity
Net income (loss)	96,302				96,302
Other comprehensive income (loss)	41,713						41,713
Cash dividends declared	(31,234)				(31,234)
Dividend equivalents declared	0			127	(127)
Share-based compensation expense	3,457			3,457
Issuance of restricted stock, net (in shares)			16,200
Issuance of restricted stock, net	0
Restricted stock surrendered and canceled (in shares)			(9,477)
Restricted stock surrendered and canceled	(29)			(29)
Exercise of stock options (in shares)			5,437
Exercise of stock options	$ 112			112
Balance at end of period (in shares) at Jun. 30, 2021	94,656,575		94,656,575
Balance at end of period at Jun. 30, 2021	$ 2,813,419		$ 931	$ 2,352,112	$ 433,852		$ 26,524