Condensed Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common stock	Paid-in capital in excess of par value	Retained earnings (deficit)	Accumulated other comprehensive income
Beginning balance at Dec. 31, 2021	$ 547,017	$ 2,420	$ 1,094,020	$ (541,164)	$ (8,259)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	7,815	19	7,796
Shares repurchased and retired related to stock-based compensation	(3,953)		(3,953)
Other comprehensive income (loss)	6,014				6,014
Net income	8,792			8,792
Ending balance at Mar. 31, 2022	565,685	2,439	1,097,863	(532,372)	(2,245)
Beginning balance at Dec. 31, 2021	547,017	2,420	1,094,020	(541,164)	(8,259)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	77,250
Ending balance at Jun. 30, 2022	644,083	2,442	1,105,006	(463,914)	549
Beginning balance at Mar. 31, 2022	565,685	2,439	1,097,863	(532,372)	(2,245)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	7,547	7	7,540
Shares repurchased and retired related to stock-based compensation	(401)	(4)	(397)
Other comprehensive income (loss)	2,794				2,794
Net income	68,458			68,458
Ending balance at Jun. 30, 2022	644,083	2,442	1,105,006	(463,914)	549
Beginning balance at Dec. 31, 2022	789,919	2,340	1,007,492	(226,195)	6,282
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	8,853	35	8,818
Shares repurchased and retired related to stock-based compensation	(9,982)	(11)	(9,971)
Shares repurchased and retired related to stock repurchase program	(53,447)	(59)	(53,388)
Other comprehensive income (loss)	(1,220)				(1,220)
Net income	253,993			253,993
Ending balance at Mar. 31, 2023	988,116	2,305	952,951	27,798	5,062
Beginning balance at Dec. 31, 2022	789,919	2,340	1,007,492	(226,195)	6,282
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Excise tax on share repurchases	(500)
Net income	404,057
Ending balance at Jun. 30, 2023	1,129,251	2,285	942,563	177,862	6,541
Beginning balance at Mar. 31, 2023	988,116	2,305	952,951	27,798	5,062
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	8,226	7	8,219
Shares repurchased and retired related to stock-based compensation	(280)	(4)	(276)
Shares repurchased and retired related to stock repurchase program	(17,857)	(23)	(17,834)
Excise tax on share repurchases	(497)		(497)
Other comprehensive income (loss)	1,479				1,479
Net income	150,064			150,064
Ending balance at Jun. 30, 2023	$ 1,129,251	$ 2,285	$ 942,563	$ 177,862	$ 6,541