Investment in NEC TOKIN Equity Loss (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Schedule of Equity Method Investments [Line Items]
Equity income (loss) from NEC TOKIN	$ 1,367	$ 1,657	$ (76)	$ (2,963)
NEC TOKIN
Schedule of Equity Method Investments [Line Items]
Net income (loss)	5,628	23,228	4,928	11,286
KEMET's equity ownership %	34.00%	34.00%	34.00%	34.00%
Equity income (loss) from NEC TOKIN before Adjustments	1,914	7,898	1,676	3,837
Amortization and depreciation	(547)	(243)	(1,752)	(1,056)
Inventory valuation	0	0	0	254
Equity income (loss) from NEC TOKIN	1,367	1,657	(76)	(2,963)
Equity Method Investment, Purchase Price Adjustment, Sale Of Land		$ (5,998)	$ 0	$ (5,998)