Fair Value Measurements - Level 3 Reconciliation (Details) (Guarantees [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Oct. 31, 2014	Oct. 31, 2013
Guarantees [Member]
Fair Value Assets And Liablities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset (Liability) Beginning Value	$ (6)	$ (7)
Transfers out of Level 3	0	0
Issuances	(2)	0
Settlements	0	1
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset (Liability) Ending Value	(8)	(6)
Change in unrealized gains on assets and liabilities still held	$ 0	$ 0