Quarterly Results (Unaudited) - Summary of Quarterly Results (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Apr. 26, 2014	Jan. 25, 2014	Oct. 26, 2013	Jul. 27, 2013	Apr. 27, 2013	Jan. 26, 2013	Oct. 27, 2012	Jul. 28, 2012	Apr. 26, 2014	Apr. 27, 2013	Apr. 28, 2012
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 1,102,077	$ 1,082,679	$ 998,834	$ 880,125	$ 964,933	$ 915,861	$ 867,193	$ 889,225	$ 4,063,715	$ 3,637,212	$ 3,535,661
Gross profit	315,868	311,461	289,431	281,518	324,177	300,293	280,599	285,700	1,198,278	1,190,769	1,162,514
Operating income	92,601	96,651	75,223	81,281	104,456	89,538	77,869	82,592	345,756	354,455	358,009
Net income	$ 55,671	$ 57,021	$ 42,028	$ 45,892	$ 63,562	$ 53,630	$ 45,542	$ 47,538	$ 200,612	$ 210,272	$ 212,815
Earnings per share - basic	$ 0.56	$ 0.56	$ 0.42	$ 0.45	$ 0.63	$ 0.53	$ 0.44	$ 0.45	$ 1.99	$ 2.04	$ 1.93
Earnings per share - diluted	$ 0.55	$ 0.56	$ 0.41	$ 0.45	$ 0.62	$ 0.52	$ 0.44	$ 0.45	$ 1.97	$ 2.03	$ 1.92