Annual report pursuant to Section 13 and 15(d)

Franchising, Marketing and Reservation Activities (Narrative) (Details)

v3.20.4
Franchising, Marketing and Reservation Activities (Narrative) (Details) - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Dec. 31, 2020
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Dec. 31, 2019
Sep. 30, 2019
Jun. 30, 2019
Mar. 31, 2019
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Disaggregation of Revenue [Line Items]                      
Net revenues $ 296 $ 337 $ 258 $ 410 $ 492 $ 560 $ 533 $ 468 $ 1,300 $ 2,053 $ 1,868
Minimum                      
Disaggregation of Revenue [Line Items]                      
Franchise/management agreement term                 10 years    
Maximum                      
Disaggregation of Revenue [Line Items]                      
Franchise/management agreement term                 20 years    
Initial franchise fee revenue                      
Disaggregation of Revenue [Line Items]                      
Net revenues                 $ 20 18 20
Forgiveness of note receivable                      
Disaggregation of Revenue [Line Items]                      
Net revenues                 $ 9 $ 8 $ 7