Long-Term Borrowings (Details) (USD $) In Millions, unless otherwise specified	Oct. 31, 2012	Oct. 31, 2011
Long-Term Borrowings
Total senior debt	$ 14,786.6	$ 11,402.6
Unamortized debt discount	(16.7)	(13.0)
Total	14,769.9	11,389.6
Principal Amounts of Long-Term Borrowings Maturing in Each of Next Five Years
2013	3,899
2014	3,528
2015	2,774
2016	1,445
2017	2,400
Medium-term notes due 2013-2023
Long-Term Borrowings
Total senior debt	14,230.3	10,687.7
Principal amount	13,759	10,372
Average interest rates (as a percent)	1.50%	2.00%
5.10% Debentures due 2013
Long-Term Borrowings
Total senior debt		678.8
Debt instrument, stated interest rate (as a percent)		5.10%
Principal amount		650
Portion of debt swapped to variable interest rates, amount		450
Variable interest rates, debt swaps (as a percent)		1.10%
2.75% Senior notes due 2022
Long-Term Borrowings
Total senior debt	518.4
Debt instrument, stated interest rate (as a percent)	2.75%
Principal amount	500
Portion of debt swapped to variable interest rates, amount	500
Variable interest rates, debt swaps (as a percent)	1.10%
Other notes
Long-Term Borrowings
Total senior debt	$ 37.9	$ 36.1