Basis of Presentation (Schedule of Disaggregated Revenue in Basis of Presentation) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Disaggregation of Revenue [Line Items]
Revenues	$ 3,039	$ 3,048	$ 5,469	$ 5,599
Avis
Disaggregation of Revenue [Line Items]
Revenues	1,718	1,747	3,090	3,207
Budget
Disaggregation of Revenue [Line Items]
Revenues	1,133	1,117	2,018	2,038
Other
Disaggregation of Revenue [Line Items]
Revenues	188	184	361	354
Americas
Disaggregation of Revenue [Line Items]
Revenues	2,332	2,361	4,239	4,354
Europe, Middle East and Africa
Disaggregation of Revenue [Line Items]
Revenues	564	544	925	926
Asia and Australasia
Disaggregation of Revenue [Line Items]
Revenues	$ 143	$ 143	$ 305	$ 319

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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