Mergers and Acquisitions (Actual and Pro Forma) - Pioneer (Details) - Pioneer Natural Resources $ in Millions	12 Months Ended
Dec. 31, 2024 USD ($)
Business Acquisition [Line Items]
Sales and other operating revenues	$ 17,008
Net income (loss) attributable to ExxonMobil	$ 1,710

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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