Schedule of intangible assets.

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

+ Details

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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- Definition

Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, from an acquisition.

+ References

No definition available.

+ Details

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Intangible Assets - Additional Information (Detail) - USD ($)					12 Months Ended
	Jul. 31, 2019	May 10, 2019	Jul. 31, 2018	Jul. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Intangible Assets [Line Items]
Impairment of intangible assets	$ 0		$ 0	$ 0
eFront [Member] \| Customer Relationships [Member]
Schedule Of Intangible Assets [Line Items]
Finite-lived intangible assets, acquired					$ 400,000,000
Acquired finite-lived intangible assets weighted-average useful life		10 years			10 years
eFront [Member] \| Technology-Related [Member]
Schedule Of Intangible Assets [Line Items]
Finite-lived intangible assets, acquired					$ 203,000,000
Acquired finite-lived intangible assets weighted-average useful life		8 years			8 years
eFront [Member] \| Trade Names [Member]
Schedule Of Intangible Assets [Line Items]
Finite-lived intangible assets, acquired					$ 14,000,000
Acquired finite-lived intangible assets weighted-average useful life		4 years			4 years
TCP Transaction [Member]
Schedule Of Intangible Assets [Line Items]
Finite-lived intangible assets, acquired						$ 48,000,000
Acquired finite-lived intangible assets weighted-average useful life						6 years
Acquired indefinite-lived management contracts						$ 145,000,000
Citibanamex Transaction [Member]
Schedule Of Intangible Assets [Line Items]
Finite-lived intangible assets, acquired						$ 31,000,000
Acquired finite-lived intangible assets weighted-average useful life						8 years
Acquired indefinite-lived management contracts						$ 255,000,000