VARIABLE INTEREST ENTITIES - Classifications of Consolidated VIE Assets and Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Variable Interest Entity [Line Items]
Financing Receivable, after Allowance for Credit Loss	$ 1,913	$ 2,233
Interest receivable	13	16
Restricted Cash and Cash Equivalents	368	414
TOTAL ASSETS	9,011	9,214
Securitized Debt	1,751	1,871
TOTAL LIABILITIES	6,328	6,183
Variable interest entity
Variable Interest Entity [Line Items]
Financing Receivable, after Allowance for Credit Loss	1,650	1,750
Restricted Cash and Cash Equivalents	69	64
TOTAL ASSETS	1,731
Securitized Debt	1,769	$ 1,871
TOTAL LIABILITIES	1,771
Variable interest entity | Debt
Variable Interest Entity [Line Items]
Securitized Debt	1,769
Variable interest entity | Vacation ownership notes receivable, net of reserves
Variable Interest Entity [Line Items]
Financing Receivable, after Allowance for Credit Loss	1,650
Variable interest entity | Interest receivable
Variable Interest Entity [Line Items]
Interest receivable	12
Variable interest entity | Restricted cash
Variable Interest Entity [Line Items]
Restricted Cash and Cash Equivalents	69
Variable interest entity | Interest payable
Variable Interest Entity [Line Items]
Interest payable	2
Variable interest entity | Vacation Ownership Notes Receivable Securitizations
Variable Interest Entity [Line Items]
TOTAL ASSETS	1,731
TOTAL LIABILITIES	1,771
Variable interest entity | Vacation Ownership Notes Receivable Securitizations | Debt
Variable Interest Entity [Line Items]
Securitized Debt	1,769
Variable interest entity | Vacation Ownership Notes Receivable Securitizations | Vacation ownership notes receivable, net of reserves
Variable Interest Entity [Line Items]
Financing Receivable, after Allowance for Credit Loss	1,650
Variable interest entity | Vacation Ownership Notes Receivable Securitizations | Interest receivable
Variable Interest Entity [Line Items]
Interest receivable	12
Variable interest entity | Vacation Ownership Notes Receivable Securitizations | Restricted cash
Variable Interest Entity [Line Items]
Restricted Cash and Cash Equivalents	69
Variable interest entity | Vacation Ownership Notes Receivable Securitizations | Interest payable
Variable Interest Entity [Line Items]
Interest payable	2
Variable interest entity | Warehouse Credit Facility
Variable Interest Entity [Line Items]
TOTAL ASSETS	0
TOTAL LIABILITIES	0
Variable interest entity | Warehouse Credit Facility | Debt
Variable Interest Entity [Line Items]
Securitized Debt	0
Variable interest entity | Warehouse Credit Facility | Vacation ownership notes receivable, net of reserves
Variable Interest Entity [Line Items]
Financing Receivable, after Allowance for Credit Loss	0
Variable interest entity | Warehouse Credit Facility | Interest receivable
Variable Interest Entity [Line Items]
Interest receivable	0
Variable interest entity | Warehouse Credit Facility | Restricted cash
Variable Interest Entity [Line Items]
Restricted Cash and Cash Equivalents	0
Variable interest entity | Warehouse Credit Facility | Interest payable
Variable Interest Entity [Line Items]
Interest payable	$ 0