Financial Instruments (Schedule of Carrying Amounts and Estimated Fair Values) (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 5,233	$ 4,791
Carrying Amount \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt and current portion of long-term debt	28	32
Long-term debt	5,233	4,791
Carrying Amount \| Interest rate caps \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swaps and interest rate caps	44	74
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	3,930	3,422
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	15,560	15,441
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	28	32
Long-term debt	5,176	4,812
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	44	74
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	3,955	3,435
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	$ 15,788	$ 15,238

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

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