| Document and Entity Information | Jan. 30, 2023 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Jan. 30, 2023 |
| Entity File Number | 000-53041 |
| Entity Registrant Name | SOUTHWEST IOWA RENEWABLE ENERGY, LLC |
| Entity Central Index Key | 0001424844 |
| Entity Incorporation, State or Country Code | IA |
| Entity Tax Identification Number | 20-2735046 |
| Entity Address, Address Line One | 10868 189th Street |
| Entity Address, City or Town | Council Bluffs |
| Entity Address, State or Province | IA |
| Entity Address, Postal Zip Code | 51503 |
| City Area Code | 712 |
| Local Phone Number | 366-0392 |
| Entity Emerging Growth Company | false |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
