Cover Page - USD ($)	12 Months Ended
	Mar. 31, 2020	May 26, 2020	Sep. 30, 2018
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Mar. 31, 2020
Document Transition Report	false
Entity File Number	001-15491
Entity Registrant Name	KEMET Corp
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	57-0923789
Entity Address, Address Line One	KEMET Tower, 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
Title of 12(b) Security	Common Stock, par value $0.01
Trading Symbol	KEM
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 1,044,995,999
Entity Common Stock, Shares Outstanding		58,508,445
Entity Central Index Key	0000887730
Amendment Flag	false
Current Fiscal Year End Date	--03-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY