Basis of Presentation - Schedule of Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disaggregation of Revenue [Line Items]
Revenues	$ 2,998	$ 3,039	$ 5,528	$ 5,469
Avis
Disaggregation of Revenue [Line Items]
Revenues	1,715	1,718	3,143	3,090
Budget
Disaggregation of Revenue [Line Items]
Revenues	1,136	1,133	2,088	2,018
Other
Disaggregation of Revenue [Line Items]
Revenues	147	188	297	361
Americas
Disaggregation of Revenue [Line Items]
Revenues	2,288	2,332	4,250	4,239
Europe, Middle East and Africa
Disaggregation of Revenue [Line Items]
Revenues	551	564	926	925
Asia and Australasia
Disaggregation of Revenue [Line Items]
Revenues	$ 159	$ 143	$ 352	$ 305

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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+ Details

- 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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+ Details