Financing Receivables and Operating Leases - Summary of the Aging and Non-accrual Status of Gross Financing Receivables (Details) - USD ($) $ in Millions	Jan. 31, 2018	Oct. 31, 2017
Billed:
Current 1-30 days	$ 298	$ 257
Past due 31-60 days	49	52
Past due 61-90 days	25	15
Past due 90 days	68	58
Unbilled sales-type and direct-financing lease receivables	7,738	7,462
Financing receivables, gross	8,178	7,844
Gross financing receivables on non-accrual status	256	188
Gross financing receivables 90 days past due and still accruing interest	$ 154	$ 133