BUSINESS SEGMENTS - Assets (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Total Assets	$ 9,018	$ 2,845
Property and equipment	951	583
United States
Segment Reporting Information [Line Items]
Property and equipment	748	506
All other countries
Segment Reporting Information [Line Items]
Property and equipment	203	77
Operating Segments
Segment Reporting Information [Line Items]
Total Assets	8,457	2,279
Operating Segments | Vacation Ownership
Segment Reporting Information [Line Items]
Total Assets	7,275	2,279
Operating Segments | Exchange & Third-Party Management
Segment Reporting Information [Line Items]
Total Assets	1,182	0
Corporate and other
Segment Reporting Information [Line Items]
Total Assets	$ 561	$ 566