Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Deficit [Member]	Retained Deficit [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance (in shares) at Dec. 31, 2018			39,506,000
Balance at Dec. 31, 2018	$ 223,590		$ 40	$ 453,193	$ (218,646)		$ (10,997)
Net income	261,575		0	0	261,575		0
Foreign currency translation	2,295		0	0	0		2,295
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax	552
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax	(1,657)		$ 0	0	0		(1,657)
Repurchases of common stock, net of retirements (in shares)			(155,000)
Repurchases of common stock, net of retirements	(23,188)		$ 0	0	(23,188)		0
Share-based compensation	13,472		$ 0	13,472	0		0
Issuance of stock under share-based compensation plans (in shares)			723,000
Issuance of stock under share-based compensation plans	18,574		$ 0	18,574	0		0
Declaration of cash dividends	(83,772)		$ 0	0	(83,772)		0
Balance (in shares) at Dec. 31, 2019			40,074,000
Balance at Dec. 31, 2019	410,180	$ (709)	$ 40	485,239	(64,740)	$ (709)	(10,359)
Net income	366,738		0	0	366,738		0
Foreign currency translation	5,210		0	0	0		5,210
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax	2,957
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax	(8,870)		$ 0	0	0		(8,870)
Repurchases of common stock, net of retirements (in shares)			(401,000)
Repurchases of common stock, net of retirements	(76,199)		$ 0	0	(76,199)		0
Share-based compensation	14,516		$ 0	14,516	0		0
Issuance of stock under share-based compensation plans (in shares)			559,000
Issuance of stock under share-based compensation plans	19,824		$ 0	19,824	0		0
Declaration of cash dividends	$ (91,929)		$ 0	0	(91,929)		0
Balance (in shares) at Dec. 31, 2020	40,232,210		40,232,000
Balance at Dec. 31, 2020	$ 639,470		$ 40	519,579	133,870		(14,019)
Net income	650,624		0	0	650,624		0
Foreign currency translation	(4,663)		0	0	0		(4,663)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax	(3,733)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax	11,198		$ 0	0	0		11,198
Repurchases of common stock, net of retirements (in shares)			(360,000)
Repurchases of common stock, net of retirements	(138,039)		$ 0	0	(138,039)		0
Share-based compensation	15,187		$ 0	15,187	0		0
Issuance of stock under share-based compensation plans (in shares)			321,000
Issuance of stock under share-based compensation plans	17,197		$ 0	17,197	0		0
Declaration of cash dividends	$ (119,581)		$ 0	0	(119,581)		0
Balance (in shares) at Dec. 31, 2021	40,192,901		40,193,000
Balance at Dec. 31, 2021	$ 1,071,393		$ 40	$ 551,963	$ 526,874		$ (7,484)