CONTINGENCIES AND COMMITMENTS (Details) $ in Millions	Sep. 30, 2020 USD ($) vacation_ownership_unit
Commitments and Contingencies Disclosure [Line Items]
Purchase commitment obligation due, thereafter	$ 3
Surety bonds issued	75
Vacation ownership projects currently under development	4
Time share, accrued costs	$ (2)
Lease not yet commenced, term of contract	16 years
Lease not yet commenced, right-of-use asset	$ 129
Revolving corporate credit facility, net
Commitments and Contingencies Disclosure [Line Items]
Letters of credit outstanding	3
Letter of credit
Commitments and Contingencies Disclosure [Line Items]
Letters of credit outstanding	2
New York City, New York
Commitments and Contingencies Disclosure [Line Items]
Purchase commitment	97
Bali Indonesia Resort Two
Commitments and Contingencies Disclosure [Line Items]
Purchase commitment obligation due, 2020	1
Purchase commitment obligation due, 2021	21
Purchase commitment obligation due, 2022	$ 2
Number of vacation ownership units expected to be acquired | vacation_ownership_unit	88
San Francisco, California
Commitments and Contingencies Disclosure [Line Items]
Purchase commitment	$ 88
Purchase commitment obligation due, 2021	32
Purchase commitment obligation due, 2022	24
Purchase commitment obligation due, 2023	32
Waikiki Hawaii
Commitments and Contingencies Disclosure [Line Items]
Purchase commitment obligation due, 2021	98
Information technology hardware and software
Commitments and Contingencies Disclosure [Line Items]
Purchase commitment	83
Purchase commitment obligation due, 2020	16
Purchase commitment obligation due, 2021	26
Purchase commitment obligation due, 2022	19
Purchase commitment obligation due, 2023	13
Purchase commitment obligation due, 2024	6
Exchange & Third-Party Management
Commitments and Contingencies Disclosure [Line Items]
Guarantor obligations, maximum exposure	28
Guarantor obligations, maximum exposure. due remainder of fiscal year	3
Guarantor obligations, maximum exposure, due in second year	10
Guarantor obligations, maximum exposure, due in third year	6
Guarantor obligations, maximum exposure, due in fourth year	3
Guarantor obligations, maximum exposure, due in five year	2
Guarantor obligations, maximum exposure, due after fifth year	$ 4