Acquisitions - Acquisitions (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($) joint_venture
Business Acquisition [Line Items]
Number of joint ventures acquired \| joint_venture	2
Management and Franchise Contracts
Business Acquisition [Line Items]
Finite lived intangible assets term	24 years
Finite lived intangible assets acquired	$ 34
Brand Assets
Business Acquisition [Line Items]
Indefinite lived intangible assets acquired	$ 156

Asset Acquisition, Number of Acquisitions

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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

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.

+ References

No definition available.

+ 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

+ Details

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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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- Details

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