Share Repurchases (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Nov. 01, 2015	Nov. 02, 2014
Statement [Line Items]
Shares repurchased, value	$ 32	$ 73
June 2011 Program [Member]
Statement [Line Items]
Authorized amount for shares repurchase	1,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 525
Treasury Stock [Member]
Statement [Line Items]
Treasury stock purchased, shares	1	2
Shares repurchased, value	$ 32	$ 73
Treasury Stock [Member] | June 2011 Program [Member]
Statement [Line Items]
Shares repurchased, value	$ 25