| Document and Entity Information | Nov. 04, 2021 |
| Cover [Abstract] | |
| Entity Registrant Name | SALEM MEDIA GROUP, INC. /DE/ |
| Entity Address, State or Province | TX |
| Amendment Flag | false |
| Entity Central Index Key | 0001050606 |
| Document Type | 8-K |
| Document Period End Date | Nov. 4, 2021 |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 000-26497 |
| Entity Tax Identification Number | 77-0121400 |
| Entity Address, Address Line One | 6400 NORTH BELT LINE ROAD |
| Entity Address, City or Town | IRVING |
| Entity Address, Postal Zip Code | 75063 |
| City Area Code | (469) |
| Local Phone Number | 586-0080 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Class A Common Stock, $0.01 par value per share |
| Trading Symbol | SALM |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
