Income Taxes (Details)	3 Months Ended		9 Months Ended
	Jan. 25, 2013	Jan. 27, 2012	Jan. 25, 2013	Jan. 27, 2012
Income Taxes [Abstract]
Effective income tax rate	35.20%	40.20%	36.60%	40.20%
Federal statutory income tax rate			35.00%