Comprehensive Income (Loss) and Shareholders' (Deficit) Equity - Amounts Reclassified out of Accumulated Other Comprehensive (Loss) Income (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Gains and other income	$ 0us-gaap_OtherNonoperatingIncomeExpense	$ 0us-gaap_OtherNonoperatingIncomeExpense
Interest expense	(36)us-gaap_InterestExpense	(30)us-gaap_InterestExpense
Income before income taxes	307	231
Provision for income taxes	100us-gaap_IncomeTaxExpenseBenefit	59us-gaap_IncomeTaxExpenseBenefit
NET INCOME	207us-gaap_NetIncomeLoss	172us-gaap_NetIncomeLoss
Foreign Currency Translation Adjustments \| Reclassification of Gains (Losses) from Accumulated Other Comprehensive Loss
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income before income taxes	(3)
Provision for income taxes	0
NET INCOME	(3)
Other Derivative Instrument Adjustments \| Reclassification of Gains (Losses) from Accumulated Other Comprehensive Loss
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income before income taxes	5
Provision for income taxes	0
NET INCOME	5
Interest rate contracts \| Other Derivative Instrument Adjustments \| Reclassification of Gains (Losses) from Accumulated Other Comprehensive Loss
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest expense	(1)
Cash flow hedges \| Other Derivative Instrument Adjustments \| Reclassification of Gains (Losses) from Accumulated Other Comprehensive Loss
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Base management and franchise fees	3
Net investment hedging \| Foreign Currency Translation Adjustments \| Reclassification of Gains (Losses) from Accumulated Other Comprehensive Loss
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Gains and other income	(3)
Net investment hedging \| Other Derivative Instrument Adjustments \| Reclassification of Gains (Losses) from Accumulated Other Comprehensive Loss
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Gains and other income	$ 3

Management Fees: Base Revenue and Franchise Fees

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- Definition

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 940

-SubTopic 20

-Section 25

-Paragraph 1

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Article 5

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

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-Article 4

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a),(b)

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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-Name Accounting Standards Codification

-Topic 942

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-Section S99

-Paragraph 1

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Article 9

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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-Publisher FASB

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Other Comprehensive Income

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Net Income

-URI http://asc.fasb.org/extlink&oid=6518256

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

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-Topic 944

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-Publisher SEC

-Name Regulation S-X (SX)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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- Definition

The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 9

-Article 5

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-Topic 225

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