Debt Under Vehicle Programs And Borrowing Arrangements (Schedule Of Debt Under Vehicle Programs) (Detail) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]
Document Period End Date	Jun. 30, 2018
Debt under vehicle programs	$ 11,776	$ 9,221
Newly Issued European Credit Facility	150
Debt Due To Avis Budget Rental Car Funding (Member)
Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]
Asset-Backed Securities, at Carrying Value	$ 400
Debt Instrument, Maturity Date	Sep. 01, 2023
Leasing Vehicles And Related Assets Pledged As Collateralized Debt	$ 9,800
Debt under vehicle programs	8,298	6,516
Deferred Finance Costs, Net	$ (33)	(36)
Debt, Weighted Average Interest Rate	4.00%
Americas Debt Borrowings [Member]
Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]
Leasing Vehicles And Related Assets Pledged As Collateralized Debt	$ 1,300
Debt under vehicle programs	912	660
International Debt Borrowings [Domain]
Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]
Leasing Vehicles And Related Assets Pledged As Collateralized Debt	2,600
Debt under vehicle programs	2,399	1,942
International Capital Leases [Domain]
Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]
Leasing Vehicles And Related Assets Pledged As Collateralized Debt	200
Debt under vehicle programs	211	146
Other (Member)
Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]
Debt under vehicle programs	4	1
Debt Under Vehicle Programs [Member]
Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]
Deferred Finance Costs, Net	$ (48)	$ (44)

Debt Under Vehicle Programs And Borrowing Arrangements [Line Items]

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- Definition

Leasing Vehicles And Related Assets, Pledged As Collateralized Debt

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- Definition

Newly Issued European Credit Facility

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- Definition

Vehicle Program Outstanding Debt

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No definition available.

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- Definition

The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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Investments in notes or bonds that are collateralized by a specific group of underlying assets owned by the issuer of the notes or bonds which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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- Definition

Weighted average interest rate of debt outstanding.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
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