ACQUISITIONS AND DISPOSITIONS - Preliminary Fair Values of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Millions		6 Months Ended
	Sep. 01, 2018	Jun. 30, 2019	Dec. 31, 2018
September 1, 2018 (as reported at December 31, 2018)
Goodwill		$ 2,824	$ 2,828
Adjustments
Adjustments		(4)
September 1, 2018 (as adjusted at June 30, 2019)
Goodwill		2,824	$ 2,828
ILG
September 1, 2018 (as reported at December 31, 2018)
Vacation ownership notes receivable	$ 753
Inventory	474
Property and equipment	373
Intangible assets	1,163
Other assets	662
Deferred revenue	(217)
Deferred taxes	(175)
Debt	(392)
Securitized debt from VIEs	(702)
Other liabilities	(548)
Net assets acquired	1,391
Goodwill	2,824
Assets acquired	4,215	4,215
Adjustments
Vacation ownership notes receivable	0
Inventory	0
Property and equipment	(1)
Intangible assets	(3)
Other assets	42
Deferred revenue	0
Deferred taxes	4
Debt	0
Securitized debt from VIEs	0
Other liabilities	(37)
Net assets acquired	5
Adjustments	(4)
Assets acquired	1
September 1, 2018 (as adjusted at June 30, 2019)
Vacation ownership notes receivable	753
Inventory	474
Property and equipment	373
Intangible assets	1,163
Other assets	662
Deferred revenue	(217)
Deferred taxes	(175)
Debt	(392)
Securitized debt from VIEs	(702)
Other liabilities	(548)
Net assets acquired	1,391
Goodwill	2,824
Assets acquired	4,215	$ 4,215
Previously Reported [Member] | ILG
September 1, 2018 (as reported at December 31, 2018)
Vacation ownership notes receivable	753
Inventory	474
Property and equipment	374
Intangible assets	1,166
Other assets	620
Deferred revenue	(217)
Deferred taxes	(179)
Debt	(392)
Securitized debt from VIEs	(702)
Other liabilities	(511)
Net assets acquired	1,386
Goodwill	2,828
Assets acquired	4,214
September 1, 2018 (as adjusted at June 30, 2019)
Vacation ownership notes receivable	753
Inventory	474
Property and equipment	374
Intangible assets	1,166
Other assets	620
Deferred revenue	(217)
Deferred taxes	(179)
Debt	(392)
Securitized debt from VIEs	(702)
Other liabilities	(511)
Net assets acquired	1,386
Goodwill	2,828
Assets acquired	$ 4,214