Cash, Cash Equivalents and Investments (Summary of Cash, Cash Equivalents and Investments) (Details) - USD ($) $ in Millions	Jan. 31, 2016	Oct. 25, 2015	Jan. 25, 2015	Oct. 26, 2014
Summary of Cash, Cash Equivalents and Investments
Cash	$ 1,861	$ 1,010
Total Cash equivalents	1,101	3,787
Total Cash and Cash equivalents	2,962	4,797	$ 2,929	$ 3,002
Short-term and long-term investments, Cost	1,131	1,095
Short-term and long-term investments, Gross Unrealized Gains	21	19
Short-term and long-term investments, Gross Unrealized Losses	2	0
Short-term and long-term investments, Estimated Fair Value	1,150	1,114
Equity investments in privately-held companies	58	78
Cash, Cash Equivalents and Investments, Cost	4,093	5,892
Cash, Cash Equivalents and Investments, Gross Unrealized Gains	21	19
Cash, Cash Equivalents and Investments, Gross Unrealized Losses	2	0
Cash, Cash Equivalents and Investments, Estimated Fair Value	4,112	5,911
Total fixed income securities [Member]
Summary of Cash, Cash Equivalents and Investments
Short-term and long-term investments, Cost	1,040	989
Short-term and long-term investments, Gross Unrealized Gains	2	2
Short-term and long-term investments, Gross Unrealized Losses	1	0
Short-term and long-term investments, Estimated Fair Value	1,041	991
U.S. Treasury and agency securities [Member]
Summary of Cash, Cash Equivalents and Investments
Short-term and long-term investments, Cost	101	84
Short-term and long-term investments, Gross Unrealized Gains	0	0
Short-term and long-term investments, Gross Unrealized Losses	0	0
Short-term and long-term investments, Estimated Fair Value	101	84
Non-US government securities [Member]
Summary of Cash, Cash Equivalents and Investments
Short-term and long-term investments, Cost	9	9
Short-term and long-term investments, Gross Unrealized Gains	0	0
Short-term and long-term investments, Gross Unrealized Losses	0	0
Short-term and long-term investments, Estimated Fair Value	9	9
Municipal securities [Member]
Summary of Cash, Cash Equivalents and Investments
Short-term and long-term investments, Cost	408	384
Short-term and long-term investments, Gross Unrealized Gains	2	2
Short-term and long-term investments, Gross Unrealized Losses	0	0
Short-term and long-term investments, Estimated Fair Value	410	386
Commercial paper, corporate bonds and medium-term notes [Member]
Summary of Cash, Cash Equivalents and Investments
Short-term and long-term investments, Cost	248	250
Short-term and long-term investments, Gross Unrealized Gains	0	0
Short-term and long-term investments, Gross Unrealized Losses	1	0
Short-term and long-term investments, Estimated Fair Value	247	250
Asset-backed and mortgage-backed securities [Member]
Summary of Cash, Cash Equivalents and Investments
Short-term and long-term investments, Cost	274	262
Short-term and long-term investments, Gross Unrealized Gains	0	0
Short-term and long-term investments, Gross Unrealized Losses	0	0
Short-term and long-term investments, Estimated Fair Value	274	262
Publicly traded equity securities [Member]
Summary of Cash, Cash Equivalents and Investments
Short-term and long-term investments, Cost	33	28
Short-term and long-term investments, Gross Unrealized Gains	19	17
Short-term and long-term investments, Gross Unrealized Losses	1	0
Short-term and long-term investments, Estimated Fair Value	51	45
Money market funds [Member]
Summary of Cash, Cash Equivalents and Investments
Total Cash equivalents	856	3,272
Non-U.S. government securities [Member]
Summary of Cash, Cash Equivalents and Investments
Total Cash equivalents	10	60
Municipal securities [Member]
Summary of Cash, Cash Equivalents and Investments
Total Cash equivalents	71	73
Commercial paper, corporate bonds and medium-term notes [Member]
Summary of Cash, Cash Equivalents and Investments
Total Cash equivalents	$ 164	$ 382