Summary of Significant Accounting Policies - Variable Interest Entities (Details) - USD ($) $ in Millions	Apr. 30, 2019	Oct. 31, 2018
Variable Interest Entity [Line Items]
Cash and cash equivalents	$ 977	$ 1,320
Variable Interest Entity Primary Beneficiary, Blue Diamond Parts [Member]
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	27	39
Cash and cash equivalents	11	4
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities	4	4
Variable Interest Entity Primary Beneficiary Securitizations Treated As Borrowings [Member] \| Financial Services Operations
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	1,300	994
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities	1,064	852
Transaction Does Not Qualify for Sale Accounting [Member] \| Financial Services Operations
Variable Interest Entity [Line Items]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	433	370
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities	$ 234	$ 205

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

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The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

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