Financial Instruments - Offsetting Assets and Liabilities (Details) - USD ($) $ in Millions	Jan. 31, 2018	Oct. 31, 2017
Derivative assets
Gross Amount Recognized	$ 121	$ 260
Gross Amount Offset	0	0
Net Amount Presented	121	260
Gross Amounts Not Offset
Derivatives	116	209
Financial Collateral	3	34
Net Amount	2	17
Derivative liabilities
Gross Amount Recognized	1,059	477
Gross Amount Offset	0	0
Net Amount Presented	1,059	477
Gross Amounts Not Offset
Derivatives	116	209
Financial Collateral	785	242
Net Amount	158	26
Cash collateral	782	220
Counterparty collateral	$ 3	$ 22