Financial Instruments - Schedule Of Carrying Amounts And Estimated Fair Values (Detail) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 5,373	$ 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	20	32
Long-term debt	5,373	4,791
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	12	74
Carrying Amount \| Vehicle-Backed Debt \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vehicle-backed debt	3,441	3,422
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	14,083	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	20	32
Long-term debt	5,452	4,812
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	12	74
Estimated Fair Value \| Vehicle-Backed Debt \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vehicle-backed debt	3,469	3,435
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	$ 14,154	$ 15,238

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

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