Stockholders' Equity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended			9 Months Ended
	Oct. 25, 2015	Jul. 26, 2015	Oct. 26, 2014	Oct. 25, 2015	Oct. 26, 2014
Accelerated Share Repurchases [Line Items]
Stock repurchase program, additional authorized amount	$ 1,620
Accelerated Share Repurchases, Payment	$ 400			$ 400
Stock Repurchased During Period, Shares	4	14		18
Accelerated Share Repurchases, Final Price Paid Per Share				$ 21.63
Aggregate number of shares repurchased under stock repurchase program (in shares)				226
Aggregated cost of shares repurchased	$ 3,720			$ 3,720
Stock Repurchase Program, Remaining Authorized Repurchase Amount	1,600			1,600
Dividends, Cash [Abstract]
Payments of Dividends	$ 53			$ 152	$ 140
Cash dividends declared and paid per common share	$ 0.0975		$ 0.0850	$ 0.2800	$ 0.2550
Authorized number of shares of common stock (in shares)	2,000			2,000
Par value of common stock	$ 0.001			$ 0.001