Financial Instruments (Details 3) (USD $) In Millions, unless otherwise specified	9 Months Ended											9 Months Ended
	Jul. 31, 2012	Oct. 31, 2011	Jul. 31, 2011 U.S. Treasury securities	Jul. 31, 2012 Other Current Assets	Oct. 31, 2011 Other Current Assets	Jul. 31, 2012 Long-term Financing Receivables and Other Assets	Oct. 31, 2011 Long-term Financing Receivables and Other Assets	Jul. 31, 2012 Other Accrued Liabilities	Oct. 31, 2011 Other Accrued Liabilities	Jul. 31, 2012 Other Liabilities	Oct. 31, 2011 Other Liabilities	Jul. 31, 2012 Cash flow hedges M Year	Jul. 31, 2012 Derivatives designated as hedging instruments	Oct. 31, 2011 Derivatives designated as hedging instruments	Jul. 31, 2012 Derivatives designated as hedging instruments Other Current Assets	Oct. 31, 2011 Derivatives designated as hedging instruments Other Current Assets	Jul. 31, 2012 Derivatives designated as hedging instruments Long-term Financing Receivables and Other Assets	Oct. 31, 2011 Derivatives designated as hedging instruments Long-term Financing Receivables and Other Assets	Jul. 31, 2012 Derivatives designated as hedging instruments Other Accrued Liabilities	Oct. 31, 2011 Derivatives designated as hedging instruments Other Accrued Liabilities	Jul. 31, 2012 Derivatives designated as hedging instruments Other Liabilities	Oct. 31, 2011 Derivatives designated as hedging instruments Other Liabilities	Jul. 31, 2012 Derivatives designated as hedging instruments Fair value hedges Interest rate contracts	Oct. 31, 2011 Derivatives designated as hedging instruments Fair value hedges Interest rate contracts	Jul. 31, 2012 Derivatives designated as hedging instruments Fair value hedges Interest rate contracts Other Current Assets	Oct. 31, 2011 Derivatives designated as hedging instruments Fair value hedges Interest rate contracts Other Current Assets	Jul. 31, 2012 Derivatives designated as hedging instruments Fair value hedges Interest rate contracts Long-term Financing Receivables and Other Assets	Oct. 31, 2011 Derivatives designated as hedging instruments Fair value hedges Interest rate contracts Long-term Financing Receivables and Other Assets	Jul. 31, 2012 Derivatives designated as hedging instruments Cash flow hedges Foreign exchange contracts	Oct. 31, 2011 Derivatives designated as hedging instruments Cash flow hedges Foreign exchange contracts	Jul. 31, 2012 Derivatives designated as hedging instruments Cash flow hedges Foreign exchange contracts Other Current Assets	Oct. 31, 2011 Derivatives designated as hedging instruments Cash flow hedges Foreign exchange contracts Other Current Assets	Jul. 31, 2012 Derivatives designated as hedging instruments Cash flow hedges Foreign exchange contracts Long-term Financing Receivables and Other Assets	Oct. 31, 2011 Derivatives designated as hedging instruments Cash flow hedges Foreign exchange contracts Long-term Financing Receivables and Other Assets	Jul. 31, 2012 Derivatives designated as hedging instruments Cash flow hedges Foreign exchange contracts Other Accrued Liabilities	Oct. 31, 2011 Derivatives designated as hedging instruments Cash flow hedges Foreign exchange contracts Other Accrued Liabilities	Jul. 31, 2012 Derivatives designated as hedging instruments Cash flow hedges Foreign exchange contracts Other Liabilities	Oct. 31, 2011 Derivatives designated as hedging instruments Cash flow hedges Foreign exchange contracts Other Liabilities	Jul. 31, 2012 Derivatives designated as hedging instruments Net investment hedges Foreign exchange contracts	Oct. 31, 2011 Derivatives designated as hedging instruments Net investment hedges Foreign exchange contracts	Jul. 31, 2012 Derivatives designated as hedging instruments Net investment hedges Foreign exchange contracts Other Current Assets	Oct. 31, 2011 Derivatives designated as hedging instruments Net investment hedges Foreign exchange contracts Other Current Assets	Jul. 31, 2012 Derivatives designated as hedging instruments Net investment hedges Foreign exchange contracts Long-term Financing Receivables and Other Assets	Oct. 31, 2011 Derivatives designated as hedging instruments Net investment hedges Foreign exchange contracts Long-term Financing Receivables and Other Assets	Jul. 31, 2012 Derivatives designated as hedging instruments Net investment hedges Foreign exchange contracts Other Accrued Liabilities	Oct. 31, 2011 Derivatives designated as hedging instruments Net investment hedges Foreign exchange contracts Other Accrued Liabilities	Jul. 31, 2012 Derivatives designated as hedging instruments Net investment hedges Foreign exchange contracts Other Liabilities	Oct. 31, 2011 Derivatives designated as hedging instruments Net investment hedges Foreign exchange contracts Other Liabilities	Jul. 31, 2012 Derivatives not designated as hedging instruments	Oct. 31, 2011 Derivatives not designated as hedging instruments	Jul. 31, 2012 Derivatives not designated as hedging instruments Other Current Assets	Oct. 31, 2011 Derivatives not designated as hedging instruments Other Current Assets	Jul. 31, 2012 Derivatives not designated as hedging instruments Long-term Financing Receivables and Other Assets	Oct. 31, 2011 Derivatives not designated as hedging instruments Long-term Financing Receivables and Other Assets	Jul. 31, 2012 Derivatives not designated as hedging instruments Other Accrued Liabilities	Oct. 31, 2011 Derivatives not designated as hedging instruments Other Accrued Liabilities	Jul. 31, 2012 Derivatives not designated as hedging instruments Other Liabilities	Oct. 31, 2011 Derivatives not designated as hedging instruments Other Liabilities	Jul. 31, 2012 Derivatives not designated as hedging instruments Foreign exchange contracts	Oct. 31, 2011 Derivatives not designated as hedging instruments Foreign exchange contracts	Jul. 31, 2012 Derivatives not designated as hedging instruments Foreign exchange contracts Other Current Assets	Oct. 31, 2011 Derivatives not designated as hedging instruments Foreign exchange contracts Other Current Assets	Jul. 31, 2012 Derivatives not designated as hedging instruments Foreign exchange contracts Long-term Financing Receivables and Other Assets	Oct. 31, 2011 Derivatives not designated as hedging instruments Foreign exchange contracts Long-term Financing Receivables and Other Assets	Jul. 31, 2012 Derivatives not designated as hedging instruments Foreign exchange contracts Other Accrued Liabilities	Oct. 31, 2011 Derivatives not designated as hedging instruments Foreign exchange contracts Other Accrued Liabilities	Jul. 31, 2012 Derivatives not designated as hedging instruments Foreign exchange contracts Other Liabilities	Oct. 31, 2011 Derivatives not designated as hedging instruments Foreign exchange contracts Other Liabilities	Jul. 31, 2012 Derivatives not designated as hedging instruments Interest rate contracts	Oct. 31, 2011 Derivatives not designated as hedging instruments Interest rate contracts	Jul. 31, 2012 Derivatives not designated as hedging instruments Interest rate contracts Long-term Financing Receivables and Other Assets	Oct. 31, 2011 Derivatives not designated as hedging instruments Interest rate contracts Long-term Financing Receivables and Other Assets	Jul. 31, 2012 Derivatives not designated as hedging instruments Interest rate contracts Other Liabilities	Oct. 31, 2011 Derivatives not designated as hedging instruments Interest rate contracts Other Liabilities	Jul. 31, 2012 Derivatives not designated as hedging instruments Other derivatives	Oct. 31, 2011 Derivatives not designated as hedging instruments Other derivatives	Jul. 31, 2012 Derivatives not designated as hedging instruments Other derivatives Other Current Assets	Oct. 31, 2011 Derivatives not designated as hedging instruments Other derivatives Other Current Assets	Jul. 31, 2012 Derivatives not designated as hedging instruments Other derivatives Long-term Financing Receivables and Other Assets	Oct. 31, 2011 Derivatives not designated as hedging instruments Other derivatives Long-term Financing Receivables and Other Assets	Jul. 31, 2012 Derivatives not designated as hedging instruments Other derivatives Other Accrued Liabilities	Oct. 31, 2011 Derivatives not designated as hedging instruments Other derivatives Other Liabilities
Cash flow hedges
Maturity period of foreign currency cash flow hedges (in months)												12
Maximum maturity period for lease-related cash flow hedges (in years)												5
Derivative disclosures
Cash held as collateral from counterparties	$ 613
Number of business days in which the funds held as collateral and posted as collateral, from/to counterparties are transferred	2 days
Cash posted as collateral to counterparties	21
Fair value of derivative instruments under collateralized arrangements			40
Total derivatives, gross notional amount	44,273	49,901											29,185	33,297									7,900	10,075					19,620	21,666									1,665	1,556									15,088	16,604									12,487	13,994									2,200	2,200					401	410
Derivative asset, fair value				585	320	540	608								541	229	450	542							23	30	340	508			496	192	84	30							22	7	26	4							44	91	90	66							42	66	36	5							32	55					2	25	22	6
Derivative liability, fair value								$ 356	$ 612	$ 135	$ 292								$ 249	$ 368	$ 75	$ 182													$ 220	$ 324	$ 53	$ 126							$ 29	$ 44	$ 22	$ 56							$ 107	$ 244	$ 60	$ 110							$ 106	$ 244	$ 23	$ 38					$ 37	$ 71							$ 1	$ 1