CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Additional Paid-In Capital	Retained Earnings Cumulative-effect adjustment of a change in accounting principle, net of tax: ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments	Retained Earnings	Accumulated other comprehensive Income (Loss)	Treasury Stock	Cumulative-effect adjustment of a change in accounting principle, net of tax: ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments	Total
Balance at Dec. 31, 2019	$ 1,399	$ 2,503,677	$ (12,517)	$ 437,072	$ (31,749)	$ (270,141)	$ (12,517)	$ 2,640,258
Balance (in shares) at Dec. 31, 2019	129,928,479
Increase (Decrease) in Stockholders' Equity
Net income				124,015				124,015
Cash dividends declared				(101,322)				(101,322)
Equity-based awards	$ 3	8,172		(933)		(1,745)		5,497
Equity-based awards (in shares)	201,069
Common stock repurchased						(5,000)		(5,000)
Common stock repurchased (in shares)	(217,759)
Other comprehensive income (loss), net of tax					83,003			83,003
Balance at Sep. 30, 2020	$ 1,402	2,511,849		446,315	51,254	(276,886)		2,733,934
Balance (in shares) at Sep. 30, 2020	129,911,789
Balance at Jun. 30, 2020	$ 1,401	2,509,271		415,296	52,731	(276,802)		2,701,897
Balance (in shares) at Jun. 30, 2020	129,866,898
Increase (Decrease) in Stockholders' Equity
Net income				65,101				65,101
Cash dividends declared				(33,775)				(33,775)
Equity-based awards	$ 1	2,578		(307)		(84)		2,188
Equity-based awards (in shares)	44,891
Other comprehensive income (loss), net of tax					(1,477)			(1,477)
Balance at Sep. 30, 2020	$ 1,402	2,511,849		446,315	51,254	(276,886)		2,733,934
Balance (in shares) at Sep. 30, 2020	129,911,789
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				208,713				$ 208,713
Cash dividends declared				(100,889)				(100,889)
Equity-based awards	$ 4	10,154		(704)		(3,086)		6,368
Equity-based awards (in shares)	252,593
Common stock repurchased						(53,495)		(53,495)
Common stock repurchased (in shares)	(1,909,295)
Other comprehensive income (loss), net of tax					(93,067)			(93,067)
Balance at Sep. 30, 2021	$ 1,406	2,524,168		581,094	(61,463)	(333,471)		$ 2,711,734
Balance (in shares) at Sep. 30, 2021	128,255,570							128,255,570
Balance at Jun. 30, 2021	$ 1,405	2,520,790		550,511	(29,702)	(311,663)		$ 2,731,341
Balance (in shares) at Jun. 30, 2021	129,019,871
Increase (Decrease) in Stockholders' Equity
Net income				64,279				64,279
Cash dividends declared				(33,441)				(33,441)
Equity-based awards	$ 1	3,378		(255)		(241)		2,883
Equity-based awards (in shares)	12,683
Common stock repurchased						(21,567)		(21,567)
Common stock repurchased (in shares)	(776,984)
Other comprehensive income (loss), net of tax					(31,761)			(31,761)
Balance at Sep. 30, 2021	$ 1,406	$ 2,524,168		$ 581,094	$ (61,463)	$ (333,471)		$ 2,711,734
Balance (in shares) at Sep. 30, 2021	128,255,570							128,255,570