Financial Instruments (Schedule Of Carrying Amounts And Estimated Fair Values) (Detail) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt and current portion of long-term debt	$ 27	$ 19
Long-term debt	4,678	3,990
Carrying Amount \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt and current portion of long-term debt	27	19
Long-term debt	4,678	3,990
Carrying Amount \| Interest rate caps \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swaps and interest rate caps	48	14
Carrying Amount \| Vehicle-backed debt due to Avis Budget Rental Car Funding \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vehicle-backed debt	2,308	2,528
Carrying Amount \| Avis budget rental car funding \| Vehicle-backed debt due to Avis Budget Rental Car Funding \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vehicle-backed debt	9,743	8,848
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	26	18
Long-term debt	4,701	4,153
Estimated Fair Value \| Interest rate caps \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swaps and interest rate caps	48	14
Estimated Fair Value \| Vehicle-backed debt due to Avis Budget Rental Car Funding \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vehicle-backed debt	2,313	2,559
Estimated Fair Value \| Avis budget rental car funding \| Vehicle-backed debt due to Avis Budget Rental Car Funding \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vehicle-backed debt	$ 9,610	$ 9,009

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

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