VACATION OWNERSHIP NOTES RECEIVABLE - Recorded Investment in Non-accrual Notes Receivable that are Ninety Days or More Past Due (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Legacy-MVW
Financing Receivable, Past Due [Line Items]
Investment in notes receivable on non-accrual status	$ 97	$ 54
Legacy-MVW | Non-Securitized
Financing Receivable, Past Due [Line Items]
Investment in notes receivable on non-accrual status	86	43
Legacy-MVW | Securitized
Financing Receivable, Past Due [Line Items]
Investment in notes receivable on non-accrual status	11	11
Legacy-ILG
Financing Receivable, Past Due [Line Items]
Investment in notes receivable on non-accrual status	108	49
Legacy-ILG | Non-Securitized
Financing Receivable, Past Due [Line Items]
Investment in notes receivable on non-accrual status	96	40
Legacy-ILG | Securitized
Financing Receivable, Past Due [Line Items]
Investment in notes receivable on non-accrual status	$ 12	$ 9