Derivative Instruments (Details 3) (Not Designated as Hedging Instruments, USD $) In Millions, unless otherwise specified	Apr. 30, 2015	Oct. 31, 2014	Apr. 30, 2014
Interest Rate Contracts
Derivatives Not Designated as Hedging Instruments
Notional amounts	$ 2,744	$ 3,076	$ 3,149
Foreign Exchange Contracts
Derivatives Not Designated as Hedging Instruments
Notional amounts	945	1,364	1,391
Cross-Currency Interest Rate Contracts
Derivatives Not Designated as Hedging Instruments
Notional amounts	94	98	88
Interest Rate Caps - Purchased
Derivatives Not Designated as Hedging Instruments
Notional amounts	1,756	1,703	1,597
Interest Rate Caps - Sold
Derivatives Not Designated as Hedging Instruments
Notional amounts	$ 1,756	$ 1,703	$ 1,597