Net purchase price.

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Transactions.

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No definition available.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of assets held-for-sale that are not part of a disposal group.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount classified as liabilities attributable to disposal group held for sale or disposed of.

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The number of businesses acquired by the entity during the period.

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Transactions - Additional Information (Detail) $ in Millions		3 Months Ended		12 Months Ended
	Jan. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2019 USD ($) Acquisition	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Transactions [Line Items]
Goodwill		$ 245		$ 245	$ 314	$ 328
Assets held-for-sale		34		34
Liabilities held-for-sale		6		6
Impairment charges		128		128
Held-for-Sale [Member]
Transactions [Line Items]
Assets held-for-sale		34		34
Liabilities held-for-sale		$ 6		6
Impairment charges				9
Held-for-Sale [Member] \| Subsequent Event [Member]
Transactions [Line Items]
Proceeds from sale of business	$ 28
Two Acquisitions [Member]
Transactions [Line Items]
Number of acquisitions \| Acquisition			2
Purchase price consideration			$ 8
Goodwill			6
Intangible assets			$ 2
Two Acquisitions [Member] \| Maximum [Member]
Transactions [Line Items]
Acquisition related costs				$ 1