Reconciliation of Basic and Diluted Income (Loss) Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Jul. 29, 2017	Jul. 30, 2016
Numerator for basic loss per share:
Net loss	$ (10,778)	$ (14,416)
Less allocation of dividends to participating securities	(11)	(203)
Net loss available to common shareholders	(10,789)	(14,619)
Numerator for diluted loss per share:
Net loss available to common shareholders	$ (10,789)	$ (14,619)
Denominator for basic and diluted loss per share:
Basic and diluted weighted average common shares	72,453	72,903
Loss per common share:
Basic	$ (0.15)	$ (0.20)
Diluted	$ (0.15)	$ (0.20)