BUSINESS SEGMENTS - Assets (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Total assets	$ 9,432	$ 9,214
Operating Segments
Segment Reporting Information [Line Items]
Total assets	8,519	8,507
Operating Segments | Vacation Ownership
Segment Reporting Information [Line Items]
Total assets	7,446	7,345
Operating Segments | Exchange & Third-Party Management
Segment Reporting Information [Line Items]
Total assets	1,073	1,162
Corporate and other
Segment Reporting Information [Line Items]
Total assets	$ 913	$ 707