Inventory (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended		12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Real Estate, Inventory [Line Items]
Transferred property and equipment to VOI inventory	$ 26	$ 58
Other Inventory, Purchased Goods, Gross	14		$ 27
Inventory sold subject to conditional repurchase	153		155
Cash consideration received	20	0
Vacation ownership inventory	57		62
Repayments of vacation ownership inventory arrangements	5	$ 0
St. Thomas, U.S. Virgin Island Inventory Sale [Member]
Real Estate, Inventory [Line Items]
Inventory sold subject to conditional repurchase			80
Cash consideration received	10		80
Avon, Colorado Inventory [Member]
Real Estate, Inventory [Line Items]
Outstanding obligation	32		32
Outstanding obligation within accrued expenses and other current liabilities	11		11
Outstanding obligation within other non-current liabilities	21		21
Las Vegas, Nevada and St. Thomas, U.S. Virgin Island Inventory Sales [Member]
Real Estate, Inventory [Line Items]
Outstanding obligation	163		157
Outstanding obligation within accrued expenses and other current liabilities	52		33
Outstanding obligation within other non-current liabilities	111		124
Maximum potential future payments	278
Las Vegas, Nevada Inventory [Member]
Real Estate, Inventory [Line Items]
Paid to third-party developer	13
Vacation ownership inventory	6
Repayments of vacation ownership inventory arrangements	5
Interest paid	2
Current [Member]
Real Estate, Inventory [Line Items]
Other Inventory, Purchased Goods, Gross	4		20
Accounts Payable [Member]
Real Estate, Inventory [Line Items]
Other Inventory, Purchased Goods, Gross	10		7
Additional [Member] | Las Vegas, Nevada Inventory [Member]
Real Estate, Inventory [Line Items]
Vacation ownership inventory	7
2015 [Member] | St. Thomas, U.S. Virgin Island Inventory Sale [Member]
Real Estate, Inventory [Line Items]
Cash consideration received			$ 70
2016 [Member] | St. Thomas, U.S. Virgin Island Inventory Sale [Member]
Real Estate, Inventory [Line Items]
Cash consideration received	$ 10