Asset Impairment - Summary of Goodwill by Reportable Segment (Detail) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Goodwill [Line Items]
Goodwill, Beginning balance	$ 245
Impairment	(230)
Foreign currency translation adjustments	(15)
United States [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	125
Impairment	(125)
Canada [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	67
Impairment	(60)
Foreign currency translation adjustments	(7)
International [Member]
Goodwill [Line Items]
Goodwill, Beginning balance	53
Impairment	(45)
Foreign currency translation adjustments	$ (8)

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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-Section 50
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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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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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