Investment in NEC TOKIN - Narrative (Details) BRL in Thousands, $ in Thousands, ¥ in Millions, TWD in Millions						8 Months Ended	12 Months Ended
	Jul. 26, 2016 USD ($)	Jul. 26, 2016 BRL	May 02, 2016 USD ($) installment suit	Sep. 02, 2015	Feb. 01, 2013 USD ($)	Apr. 30, 2015 USD ($) number_of_times	Mar. 31, 2017 USD ($) item	Mar. 31, 2017 JPY (¥) item	Mar. 31, 2017 TWD item	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2016	Mar. 12, 2012 director_position	May 05, 2010
Schedule of Equity Method Investments [Line Items]
Gain (loss) on options							$ 10,700			$ (26,300)	$ 2,100
Forward Option Net Asset Liability at Fair Value							$ (9,900)			(20,600)
Document Period End Date							Mar. 31, 2017	Mar. 31, 2017	Mar. 31, 2017
KEC
Schedule of Equity Method Investments [Line Items]
Business Combination, Indemnification Assets, Range of Outcomes, Value, Low							$ (8,500)
NECTOKIN
Schedule of Equity Method Investments [Line Items]
Loss Contingency, Estimate of Possible Loss							83,400
Stockholders Agreement | KEC
Schedule of Equity Method Investments [Line Items]
Receivables balance under agreement							775			748
NECTOKIN
Schedule of Equity Method Investments [Line Items]
Revenue from Related Parties							17,100			21,061	13,500
Related Party Transaction, Purchases from Related Party							8,341			5,912	$ 3,605
Accounts receivable							2,662			5,220
Accounts payable							$ 1,378			$ 1,019
NECTOKIN | KEC
Schedule of Equity Method Investments [Line Items]
Purchase price					$ 54,500
Transaction expenses					4,500
NECTOKIN | Stock Purchase Agreement | KEC
Schedule of Equity Method Investments [Line Items]
Common stock acquired													51.00%
KEMET’s equity ownership %							34.00%			34.00%	34.00%		34.00%
Purchase price paid					50,000
Investment in NEC TOKIN (excludes non cash investment)					$ 50,000
NECTOKIN | Stockholders Agreement
Schedule of Equity Method Investments [Line Items]
Number of director positions | director_position													7
NECTOKIN | Stockholders Agreement | KEC
Schedule of Equity Method Investments [Line Items]
Number of director positions | director_position													4
NECTOKIN | Option Agreement | KEC
Schedule of Equity Method Investments [Line Items]
Common stock acquired						51.00%
Purchase price for expected additional shares that may be acquired						$ 50,000
Economic Ownership, Percentage of Ownership After Transaction						49.00%
LTM EBITDA multiple | number_of_times						6
NECTOKIN | Put Option
Schedule of Equity Method Investments [Line Items]
Forward Option Net Asset Liability at Fair Value							$ (9,900)			$ (20,600)
Level 3 | Recurring | NECTOKIN | Put Option
Schedule of Equity Method Investments [Line Items]
Gain (loss) on options							10,700			(26,300)	$ 2,100
Equity Method Investments | Stockholders Agreement | NECTOKIN
Schedule of Equity Method Investments [Line Items]
Business Combination, Indemnification Assets, Range of Outcomes, Value, Low							(25,000)
Indemnification Agreement | Equity Method Investments
Schedule of Equity Method Investments [Line Items]
Litigation Settlement, Amount							13,800
Indemnification Agreement | Equity Method Investments | NECTOKIN
Schedule of Equity Method Investments [Line Items]
Litigation Settlement, Amount			$ 37,300
Litigation Settlement, Number of Payment Installments | installment			5
Settled Litigation [Member] | Indemnification Agreement | Equity Method Investments
Schedule of Equity Method Investments [Line Items]
Litigation Settlement, Amount							$ 2,300
Litigation Settlement, Payment Period				5 years
Fine, Number of Payments | item							6	6	6
Preliminary Settlement | Indemnification Agreement | Equity Method Investments | NECTOKIN
Schedule of Equity Method Investments [Line Items]
Loss Contingency, Pending Claims, Number | suit			2
Pending Litigation | KEC
Schedule of Equity Method Investments [Line Items]
Loss Contingency, Loss in Period							$ 7,100
TAIWAN, PROVINCE OF CHINA
Schedule of Equity Method Investments [Line Items]
Loss Contingency, Damages Sought, Value							40,200		TWD 1,218.2
TAIWAN, PROVINCE OF CHINA | Minimum
Schedule of Equity Method Investments [Line Items]
Loss Contingency, Damages Sought, Value							20,100		TWD 609.1
JAPAN
Schedule of Equity Method Investments [Line Items]
Litigation Settlement, Amount							$ 1,100	¥ 127.2
BRAZIL | Settled Litigation [Member]
Schedule of Equity Method Investments [Line Items]
Loss Contingency, Damages Paid, Value	$ 200	BRL 601
10.5% Senior Notes
Schedule of Equity Method Investments [Line Items]
Stated interest rate (as a percent)							10.50%					10.50%		10.50%
Other Noncurrent Assets [Member] | Level 3 | Recurring | NECTOKIN | Put Option
Schedule of Equity Method Investments [Line Items]
Forward Option Net Asset Liability at Fair Value							$ (9,900)			(20,600)	$ 5,700
Other Assets [Member] | Level 3 | Recurring | NECTOKIN | Put Option
Schedule of Equity Method Investments [Line Items]
Forward Option Net Asset Liability at Fair Value										$ (20,600)