Commitment to Purchase a percentage of Equity Ownership at a future point in time.

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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-Name Accounting Standards Codification
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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

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- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Acquisitions and Other Investments (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Goodwill	$ 1,064			$ 1,064		$ 1,073
Income (Loss) from Equity Method Investments	0		$ 0	0	$ 0
2018 Avis and Budget Licensees [Member]
Schedule of Equity Method Investments [Line Items]
Business Combination, Consideration Transferred				$ 31
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life				2 years
Morini S.p.A. [Member]
Schedule of Equity Method Investments [Line Items]
Business Combination, Consideration Transferred				$ 40
Business Combination, Contingent Consideration, Liability	6			6
Payments to Acquire Businesses, Gross	32
Goodwill	21			$ 21
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life				14 years
Greece [Member]
Schedule of Equity Method Investments [Line Items]
Payments to Acquire Equity Method Investments	$ 18	$ 19
Equity Method Investment, Ownership Percentage	40.00%	20.00%		40.00%
Equity Method Investment, Commitment to Purchase Ownership Percentage		20.00%
Income (Loss) from Equity Method Investments				$ 7
Commitment to Purchase within next 12 months [Member] \| Greece [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Commitment to Purchase Ownership Percentage		10.00%
Commitment to Purchase in year 2 [Member] \| Greece [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Commitment to Purchase Ownership Percentage		10.00%
Licensing Agreements [Member] \| 2018 Avis and Budget Licensees [Member]
Schedule of Equity Method Investments [Line Items]
Finite-lived Intangible Assets Acquired				36
Licensing Agreements [Member] \| Morini S.p.A. [Member]
Schedule of Equity Method Investments [Line Items]
Finite-lived Intangible Assets Acquired				19
Customer Relationships [Member] \| Morini S.p.A. [Member]
Schedule of Equity Method Investments [Line Items]
Finite-lived Intangible Assets Acquired				3
Other Intangible Assets [Member] \| Morini S.p.A. [Member]
Schedule of Equity Method Investments [Line Items]
Finite-lived Intangible Assets Acquired				$ 3