Condensed Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Additional Paid-in Capital	Treasury Stock	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Income (Loss)
Beginning balance (in shares) at Dec. 31, 2018			48,809		2,166
Beginning balance at Dec. 31, 2018	$ 638,990		$ 488	$ 452,730	$ (100,438)	$ 286,059		$ 151
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase of common stock into treasury (in shares)					(378)
Repurchase of common stock into treasury	(17,930)				$ (17,930)
Equity awards vested and exercised, net of shares withheld for payroll taxes (in shares)			313
Equity awards vested and exercised, net of shares withheld for payroll taxes	(10,281)		$ 3	(10,284)
Share-based compensation	5,186			5,186
Comprehensive income (loss)	34,021					34,122		(101)
Ending balance (in shares) at Mar. 31, 2019			49,122		2,544
Ending balance at Mar. 31, 2019	649,986		$ 491	447,632	$ (118,368)	320,181		50
Beginning balance (in shares) at Dec. 31, 2018			48,809		2,166
Beginning balance at Dec. 31, 2018	638,990		$ 488	452,730	$ (100,438)	286,059		151
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	86,448
Ending balance (in shares) at Sep. 30, 2019			49,271		2,561
Ending balance at Sep. 30, 2019	705,104		$ 493	451,096	$ (119,143)	372,565		93
Beginning balance (in shares) at Dec. 31, 2018			48,809		2,166
Beginning balance at Dec. 31, 2018	638,990		$ 488	452,730	$ (100,438)	286,059		151
Ending balance (in shares) at Dec. 31, 2019			49,283		2,561
Ending balance at Dec. 31, 2019	$ 736,742	$ (1,154)	$ 493	455,193	$ (119,143)	400,047	$ (1,154)	152
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
Beginning balance (in shares) at Mar. 31, 2019			49,122		2,544
Beginning balance at Mar. 31, 2019	$ 649,986		$ 491	447,632	$ (118,368)	320,181		50
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Repurchase of common stock into treasury (in shares)					(17)
Repurchase of common stock into treasury	(775)				$ (775)
Equity awards vested and exercised, net of shares withheld for payroll taxes (in shares)			101
Equity awards vested and exercised, net of shares withheld for payroll taxes	(1,253)		$ 1	(1,254)
Share-based compensation	3,702			3,702
Comprehensive income (loss)	28,780					28,869		(89)
Ending balance (in shares) at Jun. 30, 2019			49,223		2,561
Ending balance at Jun. 30, 2019	680,440		$ 492	450,080	$ (119,143)	349,050		(39)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity awards vested and exercised, net of shares withheld for payroll taxes (in shares)			48
Equity awards vested and exercised, net of shares withheld for payroll taxes	(1,808)		$ 1	(1,809)
Share-based compensation	2,825			2,825
Comprehensive income (loss)	23,647					23,515		132
Ending balance (in shares) at Sep. 30, 2019			49,271		2,561
Ending balance at Sep. 30, 2019	705,104		$ 493	451,096	$ (119,143)	372,565		93
Beginning balance (in shares) at Dec. 31, 2019			49,283		2,561
Beginning balance at Dec. 31, 2019	736,742	(1,154)	$ 493	455,193	$ (119,143)	400,047	(1,154)	152
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity awards vested and exercised, net of shares withheld for payroll taxes (in shares)			140
Equity awards vested and exercised, net of shares withheld for payroll taxes	(4,353)		$ 1	(4,354)
Share-based compensation	4,927			4,927
Comprehensive income (loss)	12,918					12,965		(47)
Ending balance (in shares) at Mar. 31, 2020			49,423		2,561
Ending balance at Mar. 31, 2020	749,080		$ 494	455,766	$ (119,143)	411,858		105
Beginning balance (in shares) at Dec. 31, 2019			49,283		2,561
Beginning balance at Dec. 31, 2019	736,742	$ (1,154)	$ 493	455,193	$ (119,143)	400,047	$ (1,154)	152
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	61,238
Ending balance (in shares) at Sep. 30, 2020			49,550		2,561
Ending balance at Sep. 30, 2020	807,073		$ 495	465,438	$ (119,143)	460,250		33
Beginning balance (in shares) at Mar. 31, 2020			49,423		2,561
Beginning balance at Mar. 31, 2020	749,080		$ 494	455,766	$ (119,143)	411,858		105
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity awards vested and exercised, net of shares withheld for payroll taxes (in shares)			119
Equity awards vested and exercised, net of shares withheld for payroll taxes	(288)		$ 1	(289)
Share-based compensation	6,347			6,347
Comprehensive income (loss)	22,267					22,325		(58)
Ending balance (in shares) at Jun. 30, 2020			49,542		2,561
Ending balance at Jun. 30, 2020	777,406		$ 495	461,824	$ (119,143)	434,183		47
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity awards vested and exercised, net of shares withheld for payroll taxes (in shares)			8
Equity awards vested and exercised, net of shares withheld for payroll taxes	(158)			(158)
Share-based compensation	3,772			3,772
Comprehensive income (loss)	26,053					26,067		(14)
Ending balance (in shares) at Sep. 30, 2020			49,550		2,561
Ending balance at Sep. 30, 2020	$ 807,073		$ 495	$ 465,438	$ (119,143)	$ 460,250		$ 33