Reconciliation of Basic and Diluted Earnings Per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Jul. 28, 2012	Jul. 30, 2011
Numerator for basic loss per share:
Net loss	$ (40,980)	$ (56,606)
Preferred stock dividends	(3,942)
Accretion of dividends on preferred stock	(316)
Net loss available to common shareholders	(45,238)	(56,606)
Numerator for diluted loss per share:
Net loss available to common shareholders	$ (45,238)	$ (56,606)
Denominator for basic and diluted loss per share:
Basic weighted average common shares	58,021	57,153
Average dilutive options
Diluted weighted average common shares	58,021	57,153
Loss per common share
Basic	$ (0.78)	$ (0.99)
Diluted	$ (0.78)	$ (0.99)