Financial Instruments - Schedule Of Carrying Amounts And Estimated Fair Values (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt and current portion of long-term debt	$ 19	$ 19
Long-term debt	3,990	4,191
Carrying Amount \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt and current portion of long-term debt	19	19
Long-term debt	3,990	4,191
Carrying Amount \| Level 2 \| Interest rate swaps and interest rate caps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swaps and interest rate caps	14	2
Carrying Amount \| Vehicle-Backed Debt \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vehicle-backed debt	2,528	1,775
Carrying Amount \| Vehicle-backed debt due to Avis Budget Rental Car Funding \| Vehicle-Backed Debt \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vehicle-backed debt	8,848	5,080
Estimated Fair Value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt and current portion of long-term debt	18	18
Long-term debt	4,153	4,337
Estimated Fair Value \| Level 2 \| Interest rate swaps and interest rate caps
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swaps and interest rate caps	14	2
Estimated Fair Value \| Vehicle-Backed Debt \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vehicle-backed debt	2,559	1,796
Estimated Fair Value \| Vehicle-backed debt due to Avis Budget Rental Car Funding \| Vehicle-Backed Debt \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vehicle-backed debt	$ 9,009	$ 5,317

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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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.

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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.

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