| Cover | Nov. 11, 2019 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Nov. 11, 2019 |
| Current Fiscal Year End Date | --03-31 |
| Entity File Number | 001-15491 |
| Entity Registrant Name | KEMET Corporation |
| Entity Central Index Key | 0000887730 |
| Entity Tax Identification Number | 57-0923789 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | KEMET Tower |
| Entity Address, Address Line Two | One East Broward Blvd. |
| Entity Address, City or Town | Fort Lauderdale |
| Entity Address, State or Province | FL |
| Entity Address, Postal Zip Code | 33301 |
| City Area Code | 954 |
| Local Phone Number | 766-2800 |
| Written Communications | false |
| Soliciting Material | true |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, par value $0.01 |
| Trading Symbol | KEM |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
