CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment	Retained Earnings	Common Stock Held in Treasury	Cumulative Effect, Period of Adoption, Adjustment	Total
Balance at beginning of period at Jan. 31, 2019	$ 264	$ 464,112	$ (15,194)		$ 758,881	$ (19,054)		$ 1,189,009
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity awards exercised/vested, net		(12,124)				12,240		116
Share-based compensation expense		13,657						13,657
Taxes paid for net share settlements		(8,367)						(8,367)
Other comprehensive loss, net			(7,866)					(7,866)
Repurchases of common stock						(35,216)		(35,216)
Net income (loss)					118,549			118,549
Balance at end of period (ASC 842) at Oct. 31, 2019				$ (9,580)			$ (9,580)
Balance at end of period at Oct. 31, 2019	264	457,278	(23,060)		867,850	(42,030)		1,260,302
Balance at beginning of period at Jul. 31, 2019	264	456,195	(16,848)		772,463	(44,254)		1,167,820
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity awards exercised/vested, net		(2,224)				2,224
Share-based compensation expense		4,308						4,308
Taxes paid for net share settlements		(1,001)						(1,001)
Other comprehensive loss, net			(6,212)					(6,212)
Net income (loss)					95,387			95,387
Balance at end of period (ASC 842) at Oct. 31, 2019				$ (9,580)			$ (9,580)
Balance at end of period at Oct. 31, 2019	264	457,278	(23,060)		867,850	(42,030)		1,260,302
Balance at beginning of period at Jan. 31, 2020	264	452,142	(18,008)		893,138	(36,864)		1,290,672
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity awards exercised/vested, net		(9,178)				9,358		180
Share-based compensation expense		4,015						4,015
Taxes paid for net share settlements		(317)						(317)
Other comprehensive loss, net			6,814					6,814
Net income (loss)					8,903			8,903
Balance at end of period at Oct. 31, 2020	264	446,662	(11,194)		902,041	(27,506)		1,310,267
Balance at beginning of period at Jul. 31, 2020	264	444,384	(18,260)		838,867	(27,506)		1,237,749
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense		2,278						2,278
Other comprehensive loss, net			7,066					7,066
Net income (loss)					63,174			63,174
Balance at end of period at Oct. 31, 2020	$ 264	$ 446,662	$ (11,194)		$ 902,041	$ (27,506)		$ 1,310,267