Income And Other Taxes (Reconciliation Between Income Tax Expense And Theoretical U.S. Tax) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income And Other Taxes [Abstract]
United States income (loss) before income taxes	$ 12,258	$ 14,786	$ 28,281
Non-U.S. income (loss) before income taxes	36,615	37,997	49,472
Income (loss) before income taxes	48,873	52,783	77,753
Theoretical tax	10,263	11,084	16,328
Effect of equity method of accounting	(1,301)	(1,341)	(2,407)
Non-U.S. taxes in excess of/(less than) theoretical U.S. tax	4,986	5,888	6,423
State taxes, net of federal tax benefit	314	57	601
Other	(452)	(259)	(769)
Total income tax expense (benefit)	13,810	15,429	20,176
ExxonMobil share of equity company income taxes	3,197	3,058	7,594
Total income tax expense (credit)	17,007	18,487	27,770
Net income (loss) including noncontrolling interests	35,063	37,354	57,577
Total income (loss) before taxes	$ 52,070	$ 55,841	$ 85,347
Effective income tax rate	33.00%	33.00%	33.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	21.00%
Effective Tax Rate [Line Items]
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	$ (28)	$ 24	$ 30
United States
Income And Other Taxes [Abstract]
Total income tax expense (benefit)	2,382	2,837	5,644
Non-U.S.
Income And Other Taxes [Abstract]
Total income tax expense (benefit)	$ 11,428	12,592	14,532
Effective Tax Rate [Line Items]
European tax impact		$ 115	$ 1,825