Long-Term Borrowings (Details) - USD ($) $ in Millions	Oct. 31, 2016	Oct. 31, 2015
Long-Term Borrowings
Total senior debt	$ 16,576.3	$ 16,995.2
Unamortized debt discount	(7.4)	(14.7)
Total	16,568.9	16,980.5
Principal Amounts of Long-Term Borrowings Maturing in Each of Next Five Years
2017	4,509.8
2018	4,408.9
2019	4,250.7
2020	2,328.8
2021	2,000.0
Medium-term notes due 2017-2026
Long-Term Borrowings
Total senior debt	16,046.0	16,482.8
Principal amount	$ 15,821.1	$ 16,243.4
Average interest rates (as a percent)	1.70%	1.30%
2.75% Senior notes due 2022
Long-Term Borrowings
Total senior debt	$ 519.0	$ 512.4
Debt instrument, stated interest rate (as a percent)	2.75%	2.75%
Principal amount	$ 500.0	$ 500.0
Portion of debt swapped to variable interest rates, amount	$ 500.0	$ 500.0
Variable interest rates, debt swaps (as a percent)	1.60%	1.10%
Other notes
Long-Term Borrowings
Total senior debt	$ 11.3