Basis of Presentation (Disaggregated Revenue in Basis of Presentation) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Disaggregation of Revenue [Line Items]
Revenues	$ 2,430	$ 2,551
Avis
Disaggregation of Revenue [Line Items]
Revenues	1,372	1,460
Budget
Disaggregation of Revenue [Line Items]
Revenues	885	921
Other
Disaggregation of Revenue [Line Items]
Revenues	173	170
Americas
Disaggregation of Revenue [Line Items]
Revenues	1,907	1,993
Europe, Middle East and Africa
Disaggregation of Revenue [Line Items]
Revenues	361	382
Asia and Australasia
Disaggregation of Revenue [Line Items]
Revenues	$ 162	$ 176

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.

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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+ Details