Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Capital Surplus	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Beginning Balance at Dec. 31, 2021	$ 3,145,424	$ 55,057	$ 1,110,520	$ 2,176,998	$ 126,314	$ (323,465)
Total comprehensive income (loss)	(447,598)			243,519	(691,117)
Dividends	(36,063)			(36,063)
Purchase of treasury stock	(31,806)					(31,806)
Issuances of equity awards, net of forfeitures	679		(6,630)			7,309
Recognition of equity-based compensation	11,223		11,223
Sale of treasury stock	285		174			111
Exercise of stock options	744		217			527
Ending Balance at Jun. 30, 2022	2,642,888	55,057	1,115,504	2,384,454	(564,803)	(347,324)
Beginning Balance at Mar. 31, 2022	2,748,405	55,057	1,109,585	2,265,129	(343,128)	(338,238)
Total comprehensive income (loss)	(84,119)			137,556	(221,675)
Dividends	(18,231)			(18,231)
Purchase of treasury stock	(9,319)					(9,319)
Recognition of equity-based compensation	5,738		5,738
Sale of treasury stock	147		90			57
Exercise of stock options	267		91			176
Ending Balance at Jun. 30, 2022	2,642,888	55,057	1,115,504	2,384,454	(564,803)	(347,324)
Beginning Balance at Dec. 31, 2022	2,667,093	55,057	1,125,949	2,536,086	(702,735)	(347,264)
Total comprehensive income (loss)	199,451			182,547	16,904
Dividends	(37,185)			(37,185)
Purchase of treasury stock	(7,902)					(7,902)
Issuances of equity awards, net of forfeitures	719		(9,764)			10,483
Recognition of equity-based compensation	8,455		8,455
Sale of treasury stock	255		115			140
Exercise of stock options	742		222			520
Ending Balance at Jun. 30, 2023	2,831,628	55,057	1,124,977	2,681,448	(685,831)	(344,023)
Beginning Balance at Mar. 31, 2023	2,814,659	55,057	1,120,877	2,609,928	(626,776)	(344,427)
Total comprehensive income (loss)	31,055			90,110	(59,055)
Dividends	(18,590)			(18,590)
Recognition of equity-based compensation	3,939		3,939
Sale of treasury stock	128		44			84
Exercise of stock options	437		117			320
Ending Balance at Jun. 30, 2023	$ 2,831,628	$ 55,057	$ 1,124,977	$ 2,681,448	$ (685,831)	$ (344,023)