Quarterly report pursuant to Section 13 or 15(d)

Segment Information (Summary of Net Revenues and Adjusted EBITDA by Segment) (Details)

v3.8.0.1
Segment Information (Summary of Net Revenues and Adjusted EBITDA by Segment) (Details) - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Dec. 31, 2017
Segment Reporting Information [Line Items]      
Net Revenues $ 302 $ 289 $ 1,280
Adjusted EBITDA 92 78  
Reportable Segments      
Segment Reporting Information [Line Items]      
Net Revenues 302 289  
Adjusted EBITDA 102 87  
Reportable Segments | Hotel Franchising      
Segment Reporting Information [Line Items]      
Net Revenues 203 191  
Adjusted EBITDA 86 78  
Reportable Segments | Hotel Management      
Segment Reporting Information [Line Items]      
Net Revenues 99 98  
Adjusted EBITDA 16 9  
Corporate and Other      
Segment Reporting Information [Line Items]      
Net Revenues 0 0  
Adjusted EBITDA $ (10) $ (9)