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.

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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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The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. 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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Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

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Amount of investment in equity security without readily determinable fair value.

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Acquisitions and Other Investments - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Jul. 27, 2017
Business Acquisition [Line Items]
Weighted average life of acquired intangible assets	2 years 10 months 24 days
Business acquisition, cash acquired	$ 1
Investments without readily determinable fair values	476	$ 371
Traveloka Holding Limited
Business Acquisition [Line Items]
Investments without readily determinable fair values	$ 70		$ 350
Travel Related Companies
Business Acquisition [Line Items]
Weighted average life of acquired intangible assets		3 years 9 months 18 days
Business acquisition, cash acquired		$ 6
Equity method investment, non-cash consideration		10
Business acquisitions, equity interest		8
Deductible for tax purposes		$ 12