CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Additional Paid-In Capital	Retained Earnings Cumulative-effect adjustment	Retained Earnings	Accumulated other comprehensive Income (loss)	Treasury Stock	Cumulative-effect adjustment	Total
Balance (ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments) at Dec. 31, 2019			$ (12,517)				$ (12,517)
Balance at Dec. 31, 2019	$ 1,399	$ 2,503,677		$ 437,072	$ (31,749)	$ (270,141)		$ 2,640,258
Balance (in shares) at Dec. 31, 2019	129,928,479
Increase (Decrease) in Stockholders' Equity
Net income				38,865				38,865
Cash dividends declared				(33,782)				(33,782)
Equity-based awards	$ 2	2,800		(315)		(1,504)		983
Equity-based awards (in shares)	117,248
Common stock repurchased						(5,000)		(5,000)
Common stock repurchased (in shares)	(217,759)
Other comprehensive income (loss), net of tax					35,878			35,878
Balance at Mar. 31, 2020	$ 1,401	2,506,477		429,323	4,129	(276,645)		2,664,685
Balance (in shares) at Mar. 31, 2020	129,827,968
Balance at Dec. 31, 2020	$ 1,402	2,514,014		473,974	31,604	(276,890)		$ 2,744,104
Balance (in shares) at Dec. 31, 2020	129,912,272							129,912,272
Increase (Decrease) in Stockholders' Equity
Net income				57,693				$ 57,693
Cash dividends declared				(33,812)				(33,812)
Equity-based awards	$ 3	3,034		(437)		(2,373)		227
Equity-based awards (in shares)	170,082
Common stock repurchased						(9,543)		(9,543)
Common stock repurchased (in shares)	(332,464)
Other comprehensive income (loss), net of tax					(75,039)			(75,039)
Balance at Mar. 31, 2021	$ 1,405	$ 2,517,048		$ 497,418	$ (43,435)	$ (288,806)		$ 2,683,630
Balance (in shares) at Mar. 31, 2021	129,749,890							129,749,890