Long-Term Debt And Borrowing Arrangements (Schedule Of Long-Term Debt) (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Document Fiscal Year Focus		2017
Other	$ 51	$ 51	$ 57
Long-term Debt, Current Maturities	26	26	279
Long-term debt	$ 3,565	$ 3,565	3,244
Five and One over Eight Senior Notes [Member] \| Long Term Borrowings [Member]
Debt Instrument [Line Items]
Debt instrument stated interest percentage	5.125%	5.125%
Five And One Over Two Senior Notes [Member] \| Long Term Borrowings [Member]
Debt Instrument [Line Items]
Debt instrument stated interest percentage	5.50%	5.50%
Six And Three Over Eight Senior Notes [Member] \| Long Term Borrowings [Member]
Debt Instrument [Line Items]
Debt instrument stated interest percentage	6.375%	6.375%
Four and One over Eight Euro-Denominated Senior Notes [Member] \| Long Term Borrowings [Member]
Debt Instrument [Line Items]
Debt instrument stated interest percentage	4.125%	4.125%
Five And One Over Four Senior Notes [Member] \| Long Term Borrowings [Member]
Debt Instrument [Line Items]
Debt instrument stated interest percentage	5.25%	5.25%
Four and One over Two Euro-Denominated Senior Notes [Member] \| Long Term Borrowings [Member]
Debt Instrument [Line Items]
Debt instrument stated interest percentage	4.50%	4.50%
Senior Notes [Member] \| Floating Rate Senior Notes Due December 2017 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 0	$ 0	249
Debt Instrument, Maturity Date, Description		December 2017
Senior Notes [Member] \| Six Euro-Denominated Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	0	$ 0	194
Debt Instrument, Maturity Date, Description		March 2021
Senior Notes [Member] \| Five and One over Eight Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	400	$ 400	400
Debt Instrument, Maturity Date, Description		June 2022
Senior Notes [Member] \| Five And One Over Two Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	675	$ 675	675
Debt Instrument, Maturity Date, Description		April 2023
Senior Notes [Member] \| Six And Three Over Eight Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	350	$ 350	350
Debt Instrument, Maturity Date, Description		April 2024
Senior Notes [Member] \| Four and One over Eight Euro-Denominated Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	354	$ 354	316
Debt Instrument, Maturity Date, Description		November 2024
Senior Notes [Member] \| Five And One Over Four Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	375	$ 375	375
Debt Instrument, Maturity Date, Description		March 2025
Senior Notes [Member] \| Four and One over Two Euro-Denominated Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	295	$ 295	0
Debt Instrument, Maturity Date, Description		May 2025
Loans Payable [Member] \| Floating Rate Term Loan Due March Two Thousand Nineteen [Member]
Debt Instrument [Line Items]
Long-term debt	$ 0	$ 0	144
Debt Instrument, Maturity Date, Description		March 2019
Loans Payable [Member] \| Floating Rate Term Loan Due March Two Thousand Twenty Two [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.75%
Long-term debt	$ 1,139	$ 1,139	816
Debt Instrument, Maturity Date, Description		March 2022
Debt Instrument, Description of Variable Rate Basis	200 basis points
Percentage Of Margin Aggregate Interest Rate	3.40%
Senior Notes and Loans Payable [Member]
Debt Instrument [Line Items]
Deferred Finance Costs, Net	$ (48)	$ (48)	(53)
Long-term Debt	$ 3,591	$ 3,591	$ 3,523

Percentage Of Margin Aggregate Interest Rate.

No definition available.

Name:	car_PercentageOfMarginAggregateInterestRate
Namespace Prefix:	car_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This is focus fiscal year of the document report in CCYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006.

+ References

No definition available.

+ Details

Name:	dei_DocumentFiscalYearFocus
Namespace Prefix:	dei_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ 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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

Name:	us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentDescriptionOfVariableRateBasis
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

+ References

+ Details

Name:	us-gaap_DebtInstrumentMaturityDateDescription
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DeferredFinanceCostsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: 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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

+ Details

Name:	us-gaap_LongTermDebtCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

+ Details

Name:	us-gaap_LongTermDebtNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of long-term debt classified as other.

+ 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))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

Name:	us-gaap_OtherLongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_DebtInstrumentAxis=car_FiveandOneoverEightSeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	car_LongTermBorrowingByTypeAxis=car_LongTermBorrowingsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=car_FiveAndOneOverTwoSeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=car_SixAndThreeOverEightSeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=car_FourandOneoverEightEuroDenominatedSeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=car_FiveAndOneOverFourSeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=car_FourandOneoverTwoEuroDenominatedSeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=car_FloatingRateSeniorNotesDueDecember2017Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=car_SixEuroDenominatedSeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LoansPayableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=car_FloatingRateTermLoanDueMarchTwoThousandNineteenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=car_FloatingRateTermLoanDueMarchTwoThousandTwentyTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=car_SeniorNotesandLoansPayableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: