Net Earnings (Loss) Per Share - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Oct. 28, 2017	Jul. 29, 2017	Oct. 29, 2016	Jul. 30, 2016	Oct. 28, 2017	Oct. 29, 2016	Dec. 14, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Average dilutive performance share units	19,000		0		9,000	0
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	918				506
Net Income (Loss) Attributable to Parent	$ 48,395		$ 29,289		$ 13,612	$ 1,373
Net Income (Loss) Attributable to Parent, Diluted
Stock Repurchase Program, Authorized Amount							$ 50,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 26,669				$ 26,669
Weighted Average Number of Shares Outstanding, Basic	46,705,000		46,170,000		46,611,000	46,259,000
Earnings Per Share, Basic	$ 1.04		$ 0.63		$ 0.29	$ 0.03
Earnings Per Share, Diluted	$ 1.03		$ 0.63		$ 0.29	$ 0.03
Average dilutive restricted stock units	162,000		364,000		389,000	339,000
Average dilutive performance shares	113,000		35,000		127,000	24,000
Average dilutive restricted shares	7,000		24,000		8,000	30,000
Average Dilutive Options	0		0		0	0
Weighted Average Number of Shares Outstanding, Diluted	47,006,000		46,593,000		47,144,000	46,652,000
Undistributed Earnings (Loss) Allocated to Participating Securities, Basic	$ (16)		$ (19)		$ (4)	$ (1)
Net Income (Loss) Available to Common Stockholders, Basic	48,379		29,270		13,608	1,372
Undistributed Earnings, Basic	16		19		4	1
Undistributed Earnings (Loss) Allocated to Participating Securities, Diluted	$ 16		$ 19		$ (4)	$ (1)