Shareholders' Equity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Apr. 27, 2012	Apr. 29, 2011	Apr. 27, 2012	Apr. 29, 2011	Jul. 29, 2011
Shareholders Equity [Abstract]
Exercise of share-based compensation awards			$ 16,729
Statement [Line Items]
Cash dividends declared (in dollars per share)	$ 0.65	$ 0.22	$ 1.15	$ 0.66
Change in the fair value of interest rate swap, net of tax	4,540	2,329	10,902	11,905
Accumulated change in fair value of interest rate swaps, net of tax	27,130		27,130		38,032	[1]
Share-based compensation expense			9,430
Tax benefit realized upon exercise of share-based compensation awards			1,921
Preferred stock, shares authorized (in shares)	100,000,000		100,000,000		100,000,000
Common Stock [Member]
Statement [Line Items]
Exercise of share-based compensation awards (in shares)			605,193
Shares of common stock repurchased (in shares)			220,400
Cost of shares repurchased			$ 12,279
Cash dividends paid (in dollars per share)			$ 0.72
Cash dividends declared (in dollars per share)	$ 0.25
Additional Cash dividends declared (in dollars per share)	$ 0.40
Dividend payment date	May 07, 2012
Additional Dividend payment date	Aug. 06, 2012
Preferred Stock [Member]
Statement [Line Items]
Preferred stock, shares authorized (in shares)	100,000,000		100,000,000
Series A Junior Participating Preferred Stock [Member]
Statement [Line Items]
Preferred stock, shares authorized (in shares)	300,000		300,000

[1] This Condensed Consolidated Balance Sheet has been derived from the audited Consolidated Balance Sheet as of July 29, 2011, as filed in the Company's Annual Report on Form 10-K for the fiscal year ended July 29, 2011.