ACQUISITIONS AND DISPOSITIONS - Additional Information (Details) $ in Millions	1 Months Ended	3 Months Ended	6 Months Ended
	Dec. 31, 2019 USD ($)	Mar. 31, 2020 USD ($) vacation_ownership_unit	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)
Business Acquisition [Line Items]
Purchase of vacation ownership units			$ 61	$ 0
New York City, New York
Business Acquisition [Line Items]
Number of vacation ownership units acquired | vacation_ownership_unit		57
Asset acquisition, consideration transferred		$ 89
Purchase of vacation ownership units	$ 20	22
Asset acquisition, recognized identifiable assets acquired, inventory		22
Asset acquisition, recognized identifiable assets acquired, property and equipment		$ 67
San Francisco, California
Business Acquisition [Line Items]
Number of vacation ownership units acquired | vacation_ownership_unit		34
Asset acquisition, consideration transferred		$ 26
Purchase of vacation ownership units		5
Asset acquisition, recognized identifiable assets acquired, inventory		18
Asset acquisition, recognized identifiable assets acquired, other assets		5
Asset acquisition, recognized identifiable assets acquired, property and equipment		$ 3