Cash and Cash Equivalents, Investments, and Funds Held for Customers - Classification on Balance Sheets (Details) - USD ($) $ in Millions	Oct. 31, 2018	Jul. 31, 2018	Oct. 31, 2017
Cash and Cash Equivalents Items [Line Items]
Cash and cash equivalents	$ 1,084	$ 1,464	$ 529
Cash and cash equivalents, fair value	1,084	1,464
Available-for-sale debt securities, amortized cost	450	454
Available-for-sale debt securities	448	452
Total cash and cash equivalents, investments, and funds held for customers, Amortized Cost	1,785	2,098
Total cash and cash equivalents, investments, and funds held for customers, Fair Value	1,783	2,096
Investments
Cash and Cash Equivalents Items [Line Items]
Available-for-sale debt securities, amortized cost	250	253
Available-for-sale debt securities	248	252
Funds held for customers
Cash and Cash Equivalents Items [Line Items]
Available-for-sale debt securities, amortized cost	438	368
Available-for-sale debt securities	438	367
Long-term investments
Cash and Cash Equivalents Items [Line Items]
Available-for-sale debt securities, amortized cost	13	13
Available-for-sale debt securities	$ 13	$ 13

Cash And Cash Equivalents And Available For Sale Securities, Amortized Cost Basis

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- Definition

Cash and Cash Equivalents and Available-for-sale Securities, Fair Value Disclosure

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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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.

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Fair value portion 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.

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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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No definition available.

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