Finance Receivables - Narrative (Details) $ in Millions	Oct. 31, 2019 USD ($)	Jul. 31, 2019 USD ($) segments
Schedule of Securitization [Line Items]
Loans and Leases Receivable, Net Amount	$ 2,200	$ 1,900
Number of Portfolio Segments for Finance Receivables \| segments		2
Trac Funding Facility [Member]
Schedule of Securitization [Line Items]
Finance Receivables Retail Accounts Collateral For Borrowed Securities	874	$ 709
Cash Collateral for Borrowed Securities	358	148
Financial Services Operations
Schedule of Securitization [Line Items]
Assets Net Of Intercompany Balances	$ 2,800	$ 2,400

Assets Net Of Intercompany Balances

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- Definition

Finance Receivables Retail Accounts Collateral For Borrowed Securities

+ References

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- Definition

Number of Portfolio Segments for Finance Receivables

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- Definition

Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.1)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.(a),2)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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