Summary of Significant Accounting Policies - Deferred Merchant Payables, Certain Risks and Concentrations, Earnings (Loss) per Common Share (Details) shares in Millions, $ in Millions |
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Dec. 31, 2018
USD ($)
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shares
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Dec. 31, 2017
USD ($)
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shares
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Dec. 31, 2016
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shares
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| Earnings (Loss) Per Common Share (EPS) | |||
| Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | 2 | 2 | 2 |
| Basic EPS (In Shares) | 74 | 75 | 75 |
| Diluted EPS (In Shares) | 74 | 75 | 75 |
| TripAdvisor | |||
| Product Information [Line Items] | |||
| Deferred merchant payable | $ | $ 164 | $ 156 | |
| Number of most significant travel partners | item | 2 | 2 | 2 |
| TripAdvisor | Expedia and Booking Holdings Inc. | Customer | Revenue | |||
| Product Information [Line Items] | |||
| Customer concentration (as a percent) | 37.00% | 43.00% | 46.00% |
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- Definition Cash, net of commissions, received by travelers at the time of booking that is due to hotels and vacation rental owners after the traveler's use. No definition available.
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- Definition The number of most significant travel partners. No definition available.
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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. No definition available.
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- Definition The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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