Cash, Cash Equivalents and Investments (Contractual Maturities) (Details) $ in Millions	Oct. 25, 2015 USD ($)
Cash and Cash Equivalents [Abstract]
Due in one year or less, Cost	$ 155
Due after one through five years, Cost	572
No single maturity date, Cost	368	[1]
Investments maturities amortized, Cost	1,095
Due in one year or less, Estimated Fair Value	156
Due after one through five years, Estimated Fair Value	573
No single maturity date, Estimated Fair Value	385	[1]
Investments maturities, Estimated Fair Value	$ 1,114

[1] Securities with no single maturity date include publicly-traded and privately-held equity securities, and asset-backed and mortgage-backed securities.