Derivative Instruments (Details 2) (USD $) In Millions, unless otherwise specified	Jul. 31, 2013	Oct. 31, 2012	Jul. 31, 2012
Interest rate contracts
Derivatives Not Designated as Hedging Instruments
Notional amounts	$ 2,874	$ 2,380	$ 2,100
Foreign Exchange Contracts
Derivatives Not Designated as Hedging Instruments
Notional amounts	1,438	1,298	1,428
Cross-Currency Interest Rate Contracts
Derivatives Not Designated as Hedging Instruments
Notional amounts	79	78	77
Interest Rate Caps- Purchased
Derivatives Not Designated as Hedging Instruments
Notional amounts	1,795	1,445	1,590
Interest Rate Caps- Sold
Derivatives Not Designated as Hedging Instruments
Notional amounts	$ 1,795	$ 1,445	$ 1,590