Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings	Treasury Stock [Member]
Balances at Jan. 31, 2015	$ 702,916	$ 4	$ 668,989	$ (502)	$ 53,710	$ (19,285)
Balances, shares at Jan. 31, 2015		39,892,540				292,263
Stock-based compensation	24,223		24,223
Issuance of restricted stock	0	$ 0	0	0	0	$ 0
Issuance of restricted stock, Shares		6,535
Vested and delivered restricted stock units	(4,863)		(4,863)
Vested and delivered restricted stock units, Shares		78,769
Exercise of stock options—including tax benefit	35,885		35,885
Exercise of stock options-including tax benefit, Shares		608,056
Repurchases of common stock	$ (238)					$ (238)
Repurchases of common stock, Shares	(2,625)	(2,625)				2,625
Equity component value of convertible note issuance-net	$ 77,192		77,192
Sale of common stock warrant	30,390		30,390
Purchase of convertible note hedge	(68,250)		(68,250)
Net income	91,103				91,103
Net gains (losses) from foreign currency translation	(2,164)			(2,164)
Net unrealized holding gains (losses) on investments	(34)			(34)
Balances at Jan. 30, 2016	886,160	$ 4	763,566	(2,700)	144,813	$ (19,523)
Balances, shares at Jan. 30, 2016		40,583,275				294,888
Stock-based compensation	28,930		28,930
Issuance of restricted stock	0	$ 0	0	0	0	$ 0
Issuance of restricted stock, Shares		33,555
Vested and delivered restricted stock units	(1,531)		(1,531)
Vested and delivered restricted stock units, Shares		88,538
Exercise of stock options—including tax benefit	(99)		(99)
Exercise of stock options-including tax benefit, Shares		123,265
Net income	5,401				5,401
Net gains (losses) from foreign currency translation	1,003			1,003
Net unrealized holding gains (losses) on investments	5			5
Balances at Jan. 28, 2017	919,869	$ 4	790,866	(1,692)	150,214	$ (19,523)
Balances, shares at Jan. 28, 2017		40,828,633				294,888
Stock-based compensation	50,283		50,283
Issuance of restricted stock, Shares		15,631
Vested and delivered restricted stock units	(4,504)		(4,504)
Vested and delivered restricted stock units, Shares		197,660
Exercise of stock options—including tax benefit	23,643		23,643
Exercise of stock options-including tax benefit, Shares		695,546
Repurchases of common stock	(1,000,328)	$ (2)				$ (1,000,326)
Repurchases of common stock, Shares		(20,220,132)				20,220,132
Retirement of treasury stock, Shares						(294,888)
Net income	2,180				2,180
Net gains (losses) from foreign currency translation	1,510			1,510
Net unrealized holding gains (losses) on investments	11			11
Balances at Feb. 03, 2018	$ (7,336)	$ 2	$ 860,288	$ (171)	$ 152,394	$ (1,019,849)
Balances, shares at Feb. 03, 2018		21,517,338				20,220,132