Variable Interest Entities (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Transfer And Financial Assets [Line Items]
Conveyed property and equipment	$ 191	$ 222	$ 235
Property and equipment transferred to VOI Inventory	50	70
Midtown 45, NYC Property [Member]
Schedule Of Transfer And Financial Assets [Line Items]
Conveyed property and equipment	28	23
Property and equipment transferred to VOI Inventory	36	55
Non Securitized Receivable [Member]
Schedule Of Transfer And Financial Assets [Line Items]
Non-securitized contract receivables	$ 909	$ 829