VACATION OWNERSHIP NOTES RECEIVABLE - Aging of Recorded Investment in Principal, Vacation Ownership Notes Receivable (Details) - Legacy-MVW - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
Total past due	$ 132	$ 94
Current	1,289	1,476
Total vacation ownership notes receivable	1,421	1,570
Non-Securitized
Financing Receivable, Past Due [Line Items]
Total past due	93	50
Current	167	222
Total vacation ownership notes receivable	260	272
Securitized
Financing Receivable, Past Due [Line Items]
Total past due	39	44
Current	1,122	1,254
Total vacation ownership notes receivable	1,161	1,298
31 – 90 days past due
Financing Receivable, Past Due [Line Items]
Total past due	35	40
31 – 90 days past due | Non-Securitized
Financing Receivable, Past Due [Line Items]
Total past due	8	7
31 – 90 days past due | Securitized
Financing Receivable, Past Due [Line Items]
Total past due	27	33
91 – 150 days past due
Financing Receivable, Past Due [Line Items]
Total past due	17	15
91 – 150 days past due | Non-Securitized
Financing Receivable, Past Due [Line Items]
Total past due	5	4
91 – 150 days past due | Securitized
Financing Receivable, Past Due [Line Items]
Total past due	12	11
Greater than 150 days past due
Financing Receivable, Past Due [Line Items]
Total past due	80	39
Greater than 150 days past due | Non-Securitized
Financing Receivable, Past Due [Line Items]
Total past due	80	39
Greater than 150 days past due | Securitized
Financing Receivable, Past Due [Line Items]
Total past due	$ 0	$ 0