Long-Term Debt And Borrowing Arrangements (Schedule Of Long-Term Debt) (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term debt	$ 1,200	$ 1,200
Other	26	26	$ 28
Short-term debt and current portion of long-term debt	19	19	19
Long-term debt	$ 3,884	$ 3,884	3,416
Long Term Borrowings [Member]
Debt Instrument [Line Items]
Debt instrument stated interest percentage	5.75%	5.75%
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%
Four and three over four Euro-Denominated Senior Notes [Member] \| Long Term Borrowings [Member]
Debt Instrument [Line Items]
Debt instrument stated interest percentage	4.75%	4.75%
Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt			336
Debt Instrument, Maturity Date, Description		July 2027
Senior Notes [Member] \| Five And One Over Two Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 100	$ 100	200
Debt Instrument, Maturity Date, Description		April 2023
Debt Instrument, Face Amount	100	$ 100
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	337	$ 337	336
Debt Instrument, Maturity Date, Description		November 2024
Senior Notes [Member] \| Floating Rate Term Loan Due February Two Thousand Twenty Seven [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	1,200	$ 1,200
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	281	$ 281	280
Debt Instrument, Maturity Date, Description		May 2025
Senior Notes [Member] \| Four and three over four Euro-Denominated Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	393	$ 393	393
Debt Instrument, Maturity Date, Description		January 2026
Senior Notes [Member] \| Ten and One over two
Debt Instrument [Line Items]
Long-term debt	485	$ 485	0
Senior Notes [Member] \| Five and three over four Senior Notes
Debt Instrument [Line Items]
Long-term debt	$ 400	400	400
Loans Payable [Member] \| Floating Rate Term Loan Due February Two Thousand Twenty Seven [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.92%
Long-term debt	$ 1,204	$ 1,204	1,112
Debt Instrument, Maturity Date, Description		August 2027
Debt Instrument, Description of Variable Rate Basis	225 basis points
Percentage Of Margin Aggregate Interest Rate	2.43%
Senior Notes and Loans Payable [Member]
Debt Instrument [Line Items]
Deferred Finance Costs, Net	$ (48)	$ (48)	(39)
Long-term Debt	$ 3,903	$ 3,903	$ 3,435

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

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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120400017&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120391452&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120398452&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

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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

- 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

+ 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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120400017&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120398452&loc=d3e534808-122878

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120391452&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://fasb.org/us-gaap/role/ref/legacyRef
-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=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120400017&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120398452&loc=d3e534808-122878

+ Details

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

- 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_DebtInstrumentAxis=car_FourandthreeoverfourEuroDenominatedSeniorNotesMember
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_FloatingRateTermLoanDueFebruaryTwoThousandTwentySevenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_DebtInstrumentAxis=car_FiveAndThreeOverFourSeniorNotesMember
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_LongtermDebtTypeAxis=car_SeniorNotesandLoansPayableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: