Derivative Instruments (Details 2) (USD $) In Millions, unless otherwise specified	Jan. 31, 2013	Oct. 31, 2012	Jan. 31, 2012
Interest rate contracts
Derivatives Not Designated as Hedging Instruments
Notional amounts	$ 2,265	$ 2,380	$ 1,916
Foreign Exchange Contracts
Derivatives Not Designated as Hedging Instruments
Notional amounts	1,615	1,298	1,164
Cross-Currency Interest Rate Contracts
Derivatives Not Designated as Hedging Instruments
Notional amounts	82	78	61
Interest Rate Caps- Purchased
Derivatives Not Designated as Hedging Instruments
Notional amounts	1,263	1,445	1,505
Interest Rate Caps- Sold
Derivatives Not Designated as Hedging Instruments
Notional amounts	$ 1,263	$ 1,445	$ 1,505