INVENTORY - Additional Information (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Inventory Disclosure [Abstract]
Real estate inventory, increase (decrease) true up (less than)	$ 3	$ 4
Inventory impairment	(5)
Amount of completed vacation ownership units classified as property and equipment	174
Deposits on future purchases of inventory	$ 42		$ 38