Financial Instruments - Schedule of Information Related to the Potential Effect of Entity's Master Netting Agreements and Collateral Security Agreements (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 31, 2018	Oct. 31, 2017
Derivative assets
Gross Amount Recognized	$ 55	$ 121
Gross Amount Offset	0	0
Net Amount Presented	55	121
Gross Amounts Not Offset
Derivatives	51	108
Financial Collateral	0	4
Net Amount	4	9
Derivative liabilities
Gross Amount Recognized	839	372
Gross Amount Offset	0	0
Net Amount Presented	839	372
Gross Amounts Not Offset
Derivatives	51	108
Financial Collateral	770	219
Net Amount	$ 18	$ 45
Period to collateralize	2 days