CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Impact of CECL Adoption	[1]	Common Stock	Additional Paid-in Capital	Accumulated Retained Earnings	Accumulated Retained Earnings Impact of CECL Adoption	[1]	Accumulated Other Comprehensive Income (Loss)
Balance at Dec. 31, 2018	$ 1,969,697			$ 617	$ 1,674,274	$ 300,407			$ (5,601)
Balance (in shares) at Dec. 31, 2018				62,480,755
Increase (Decrease) in Stockholders' Equity
Net (loss) income	77,245					77,245
Other comprehensive income	27,959								27,959
Repurchase and retirement of common stock	(65,969)			$ (22)	(59,253)	(6,694)
Repurchase and retirement of common stock (in shares)				(2,219,246)
Cash dividends declared	(27,541)					(27,541)
Dividend equivalents declared	0				51	(51)
Share-based compensation expense	5,313				5,313
Issuance of restricted stock, net	0
Issuance of restricted stock, net (in shares)				304,754
Restricted stock surrendered and canceled	(2,629)				(2,629)
Restricted stock surrendered and canceled (in shares)				(99,206)
Exercise of stock options	381				381
Exercise of stock options (in shares)				42,937
Balance at Jun. 30, 2019	1,984,456			$ 595	1,618,137	343,366			22,358
Balance (in shares) at Jun. 30, 2019				60,509,994
Balance at Dec. 31, 2018	1,969,697			$ 617	1,674,274	300,407			(5,601)
Balance (in shares) at Dec. 31, 2018				62,480,755
Balance at Dec. 31, 2019	$ 2,012,594	$ (45,625)		$ 586	1,594,434	396,051	$ (45,625)		21,523
Balance (in shares) at Dec. 31, 2019	59,506,057			59,506,057
Increase (Decrease) in Stockholders' Equity
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Balance at Mar. 31, 2019	$ 2,007,064			$ 617	1,676,024	325,363			5,060
Balance (in shares) at Mar. 31, 2019				62,773,299
Increase (Decrease) in Stockholders' Equity
Net (loss) income	38,527					38,527
Other comprehensive income	17,298								17,298
Repurchase and retirement of common stock	(65,969)			$ (22)	(59,253)	(6,694)
Repurchase and retirement of common stock (in shares)				(2,219,246)
Cash dividends declared	(13,792)					(13,792)
Dividend equivalents declared	0				38	(38)
Share-based compensation expense	2,860				2,860
Issuance of restricted stock, net	0
Issuance of restricted stock, net (in shares)				15,000
Restricted stock surrendered and canceled	(1,582)				(1,582)
Restricted stock surrendered and canceled (in shares)				(61,927)
Exercise of stock options	50				50
Exercise of stock options (in shares)				2,868
Balance at Jun. 30, 2019	1,984,456			$ 595	1,618,137	343,366			22,358
Balance (in shares) at Jun. 30, 2019				60,509,994
Balance at Dec. 31, 2019	$ 2,012,594	(45,625)		$ 586	1,594,434	396,051	(45,625)		21,523
Balance (in shares) at Dec. 31, 2019	59,506,057			59,506,057
Increase (Decrease) in Stockholders' Equity
Net (loss) income	$ 25,740
Other comprehensive income	22,886
Balance at Mar. 31, 2020	2,002,917			$ 586	1,596,680	361,242			44,409
Balance (in shares) at Mar. 31, 2020				59,975,281
Balance at Dec. 31, 2019	$ 2,012,594	$ (45,625)		$ 586	1,594,434	396,051	$ (45,625)		21,523
Balance (in shares) at Dec. 31, 2019	59,506,057			59,506,057
Increase (Decrease) in Stockholders' Equity
Net (loss) income	$ (73,351)					(73,351)
Other comprehensive income	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	0
Issuance of restricted stock, net (in shares)				473,509
Issuance of common stock - acquisition	749,603			$ 344	749,259
Issuance of common stock - acquisition (in shares)				34,407,403
Restricted stock surrendered and canceled	(1,273)				(1,273)
Restricted stock surrendered and canceled (in shares)				(94,306)
Exercise of stock options	1,024				1,024
Exercise of stock options (in shares)				58,239
Balance at Jun. 30, 2020	$ 2,654,647			$ 930	2,348,415	247,078			58,224
Balance (in shares) at Jun. 30, 2020	94,350,902			94,350,902
Balance at Mar. 31, 2020	$ 2,002,917			$ 586	1,596,680	361,242			44,409
Balance (in shares) at Mar. 31, 2020				59,975,281
Increase (Decrease) in Stockholders' Equity
Net (loss) income	(99,091)					(99,091)
Other comprehensive income	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	0
Issuance of restricted stock, net (in shares)				23,229
Issuance of common stock - acquisition	749,603			$ 344	749,259
Issuance of common stock - acquisition (in shares)				34,407,403
Restricted stock surrendered and canceled	(265)				(265)
Restricted stock surrendered and canceled (in shares)				(61,367)
Exercise of stock options	121				121
Exercise of stock options (in shares)				6,356
Balance at Jun. 30, 2020	$ 2,654,647			$ 930	$ 2,348,415	$ 247,078			$ 58,224
Balance (in shares) at Jun. 30, 2020	94,350,902			94,350,902

[1] Related to the adoption of Accounting Standards Update 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. See Note 2 - Recently Issue Accounting Pronouncements for further discussion.