| Document and Entity Information | Oct. 04, 2024 |
| Document And Entity Information [Line Items] | |
| Entity Registrant Name | EXXON MOBIL CORP |
| Amendment Flag | false |
| Entity Central Index Key | 0000034088 |
| Document Type | 8-K |
| Document Period End Date | Oct. 04, 2024 |
| Entity Incorporation State Country Code | NJ |
| Entity File Number | 1-2256 |
| Entity Tax Identification Number | 13-5409005 |
| Entity Address, Address Line One | 22777 Springwoods Village Parkway |
| Entity Address, City or Town | Spring |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 77389-1425 |
| City Area Code | (972) |
| Local Phone Number | 940-6000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Common Stock [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Common Stock, without par value |
| Trading Symbol | XOM |
| Security Exchange Name | NYSE |
| Zero Point Five Two Four Percent Notes Due 2028 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | 0.524% Notes due 2028 |
| Trading Symbol | XOM28 |
| Security Exchange Name | NYSE |
| Zero Point Five Two Four Percent Notes Due 2032 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | 0.835% Notes due 2032 |
| Trading Symbol | XOM32 |
| Security Exchange Name | NYSE |
| One Point Four Zero Eight Percent Notes Due 2039 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | 1.408% Notes due 2039 |
| Trading Symbol | XOM39A |
| Security Exchange Name | NYSE |
