Financial Instruments - Schedule Of Carrying Amounts And Estimated Fair Values (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 4,791	$ 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	32	27
Long-term debt	4,791	4,644
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	74	111
Carrying Amount | Vehicle-Backed Debt | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vehicle-backed debt	3,422	2,423
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	15,441	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	32	26
Long-term debt	4,812	4,411
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	74	111
Estimated Fair Value | Vehicle-Backed Debt | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Vehicle-backed debt	3,435	2,422
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	$ 15,238	$ 10,848