| Cover Page | Aug. 05, 2020 | Jun. 30, 2020 |
| Cover [Abstract] | ||
| Document Type | 8-K | |
| Document Period End Date | Aug. 5, 2020 | |
| Entity Registrant Name | Quantum Corporation | |
| Entity Incorporation, State or Country Code | DE | |
| Entity Tax Identification Number | 94-2665054 | |
| Entity Address, Address Line One | 224 Airport Parkway | |
| Entity Address, Address Line Two | Suite 550 | |
| Entity Address, City or Town | San Jose | |
| Entity Address, State or Province | CA | |
| Entity Address, Postal Zip Code | 95110 | |
| City Area Code | (408) | |
| Local Phone Number | 944-4000 | |
| Title of 12(b) Security | Common Stock, $0.01 par value per share | |
| Trading Symbol | QMCO | |
| Security Exchange Name | NASDAQ | |
| Written Communications | false | |
| Soliciting Material | false | |
| Pre-commencement Tender Offer | false | |
| Pre-commencement Issuer Tender Offer | false | |
| Entity Emerging Growth Company | false | |
| Entity Central Index Key | 0000709283 | |
| Amendment Flag | false | |
| Entity File Number | 001-13449 |
