Intangible Assets (Change in Goodwill) (Details) $ in Millions |
3 Months Ended |
|---|---|
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Mar. 31, 2018
USD ($)
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| Goodwill [Roll Forward] | |
| Balance as of December 31, 2017 | $ 423 |
| Adjustments to Goodwill | (2) |
| Balance as of March 31, 2018 | 421 |
| Hotel Franchising | |
| Goodwill [Roll Forward] | |
| Balance as of December 31, 2017 | 385 |
| Adjustments to Goodwill | (2) |
| Balance as of March 31, 2018 | 383 |
| Hotel Management | |
| Goodwill [Roll Forward] | |
| Balance as of December 31, 2017 | 38 |
| Adjustments to Goodwill | 0 |
| Balance as of March 31, 2018 | $ 38 |
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- Definition 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://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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