Acquisitions and Dispositions - Dispositions and Planned Dispositions (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current assets of dispositions	$ 31	$ 78
North American, plot of land
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash received from sale of land	46
Miami Beach EDITION Residences
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current assets of dispositions	31
Current liabilities of dispositions	$ 2