Financial Instruments - Offsetting Assets and Liabilities (Details) - USD ($) $ in Millions	Jul. 31, 2017	Oct. 31, 2016
Derivative assets
Gross Amount Recognized	$ 238	$ 720
Gross Amount Offset	0	0
Net Amount Presented	238	720
Gross Amounts Not Offset
Derivatives	196	207
Financial Collateral	50	465
Net Amount	(8)	48
Derivative liabilities
Gross Amount Recognized	709	219
Gross Amount Offset	0	0
Net Amount Presented	709	219
Gross Amounts Not Offset
Derivatives	196	207
Financial Collateral	374	10
Net Amount	139	$ 2
Cash collateral	335
Counterparty collateral	$ 39