Commitments and Contingencies - Guarantees (Details) € in Millions, SGD in Millions, $ in Millions	9 Months Ended
	Sep. 30, 2016 SGD	Sep. 30, 2016 USD ($)	Sep. 30, 2016 EUR (€)	Dec. 30, 2011 USD ($)	Sep. 09, 2005 EUR (€)
Primary Obligor
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings		$ 251
Recorded Liability for Guarantees		60
Secondarily Liable
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings		48
Secondarily Liable | MVW Spin-off
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings	SGD 5	4
Guarantee obligations, carrying value		1
Other noncurrent liabilities | Primary Obligor
Commitments and Contingencies Disclosure [Line Items]
Recorded Liability for Guarantees		60
Debt service | Primary Obligor
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings		122
Recorded Liability for Guarantees		22
Debt service | Primary Obligor | New York City EDITION Hotel
Commitments and Contingencies Disclosure [Line Items]
Guarantor obligations, term	2 years
Guarantor obligations, extended term	3 years
Debt service | Primary Obligor | Not Yet In Effect Condition
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings		14
Debt service | Primary Obligor | Not Yet In Effect Condition | New York City EDITION Hotel
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings		315
Operating profit | Primary Obligor
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings		121
Recorded Liability for Guarantees		37
Operating profit | Primary Obligor | Not Yet In Effect Condition
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings		51
Other | Primary Obligor
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings		8
Recorded Liability for Guarantees		1
Lease Obligations and Debt Securities Payable | Secondarily Liable
Commitments and Contingencies Disclosure [Line Items]
Guarantee obligations, carrying value		2
Debt Securities Payable | Secondarily Liable
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings		13
Debt Securities Payable | Secondarily Liable | Sunrise Senior Living Inc
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings		2
Debt Securities Payable | Secondarily Liable | CNL Retirement Properties Inc
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings		11
Property Lease Guarantee | Secondarily Liable | Sunrise Senior Living Inc
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings		35
Guarantee obligations, cash collateralized				$ 1
Collateral for continuing lease obligation contingency, future minimum annual payments due from 2014 until 2018				1
Property Lease Guarantee | Secondarily Liable | Sunrise Senior Living Inc | Key Bank | Letter of Credit
Commitments and Contingencies Disclosure [Line Items]
Letter of credit provided by Sunrise, amount available				$ 85
Letter of credit provided by Sunrise, amount available at period end		45
Property Lease Guarantee | Secondarily Liable | Renaissance Hotel Group N.V.
Commitments and Contingencies Disclosure [Line Items]
Guarantee obligations, cash collateralized		2	€ 2		€ 35
Annual rent payments, approximately		4
Remaining rent payments, approximately		16
Property Lease Guarantee | Secondarily Liable | Lease is Terminated by End of 2019 | ExecuStay
Commitments and Contingencies Disclosure [Line Items]
Maximum Potential Amount of Future Fundings		$ 6
Minimum
Commitments and Contingencies Disclosure [Line Items]
Funding guarantees, term	3 years
Maximum
Commitments and Contingencies Disclosure [Line Items]
Funding guarantees, term	10 years