Income Taxes - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Oct. 26, 2013	Oct. 27, 2012	Oct. 26, 2013	Oct. 27, 2012
Income Taxes [Line Items]
Income Tax Expense (Benefit)	$ 1,201	$ 306	$ 16,727	$ (21,093)
Income (Loss) before taxes	14,430	807	(57,066)	(60,420)
Effective income tax rate	8.30%	37.90%	(29.30%)	34.90%
Unrecognized tax benefits, all of which, if recognized, would affect effective tax rate	28,945		28,945
Accrued interest and penalties included in unrecognized tax benefits	10,705		10,705
Unrecognized tax benefits	$ 28,945		$ 28,945