Investment in NEC TOKIN (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015	Mar. 12, 2012
Adjustments:
Equity income (loss) from TOKIN	$ 41,643	$ (16,406)	$ (2,169)
NECTOKIN
Schedule of Equity Method Investments [Line Items]
Net income (loss)	128,502	(42,995)	(24,091)
Equity Method Investment, Equity Income (Loss) Before Adjustments	43,691	(14,618)	(8,191)
Adjustments:
Amortization and depreciation	(2,210)	(1,625)	(2,270)
Equity Method Investment, Indemnity Asset Change	0	0	(8,500)
Equity Method investment, Purchase Price Adjustment, Inventory Profit Elimination	162	(163)	(208)
Equity income (loss) from TOKIN	$ 41,643	$ (16,406)	$ (2,169)
KEMET Electronics Corporation [Member] | Stock Purchase Agreement [Member] | NECTOKIN
Schedule of Equity Method Investments [Line Items]
KEMET’s equity ownership %	34.00%	34.00%	34.00%	34.00%