Financial Instruments (Schedule of Carrying Amounts and Estimated Fair Values) (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 5,429	$ 5,373
Carrying Amount | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt and current portion of long-term debt	508	20
Long-term debt	5,429	5,373
Carrying Amount | Interest rate caps | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swaps and interest rate caps	3	12
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	3,442	3,441
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	13,794	14,083
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	510	20
Long-term debt	5,295	5,452
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	3	12
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	3,470	3,469
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	$ 13,911	$ 14,154