Financial Instruments (Schedule Of Carrying Amounts And Estimated Fair Values) (Detail) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt and current portion of long-term debt	$ 34	$ 27
Long-term debt	4,662	4,644
Carrying Amount \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt and current portion of long-term debt	34	27
Long-term debt	4,662	4,644
Carrying Amount \| Interest Rate Caps \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swaps and interest rate caps	98	111
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	2,473	2,423
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	12,206	11,275
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	34	26
Long-term debt	4,604	4,411
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	98	111
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	2,471	2,422
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	$ 11,847	$ 10,848

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

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