| Cover | Jun. 22, 2022 |
| Cover [Abstract] | |
| Entity Registrant Name | Blue Dolphin Energy Company |
| Entity Central Index Key | 0000793306 |
| Document Type | 8-K |
| Amendment Flag | false |
| Entity Emerging Growth Company | false |
| Document Period End Date | Jun. 22, 2022 |
| Entity Incorporation State Country Code | DE |
| Entity Tax Identification Number | 73-1268729 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Entity File Number | 0-15905 |
| Entity Address Address Line 1 | 801 Travis Street |
| Entity Address Address Line 2 | Suite 2100 |
| Entity Address City Or Town | Houston |
| Entity Address State Or Province | TX |
| Entity Address Postal Zip Code | 77002 |
| City Area Code | 713 |
| Local Phone Number | 568-4725 |
| Security 12b Title | Common Stock, par value $0.01 per share |
| Trading Symbol | BDCO |
