Quarterly report pursuant to Section 13 or 15(d)

Transactions With Former Parent (Narrative) (Details)

v3.10.0.1
Transactions With Former Parent (Narrative) (Details) - Wyndham Worldwide - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2018
Sep. 30, 2017
Dec. 31, 2017
Related Party Transaction [Line Items]        
Outstanding borrowings from Parent       $ 184
Revenue from former parent $ 4 $ 4    
Information technology support, financial services, human resources and other shared services        
Related Party Transaction [Line Items]        
Expense for services provided by Parent   13 $ 21  
Indirect general corporate overhead allocations        
Related Party Transaction [Line Items]        
Expense for services provided by Parent   12 25  
Insurance        
Related Party Transaction [Line Items]        
Expense for services provided by Parent   1 2  
Defined contribution benefit plan        
Related Party Transaction [Line Items]        
Expense for services provided by Parent   $ 2 $ 4