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- Definition

Litigation Settlement, Payment Period

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

Amount of damages paid to the plaintiff in the legal matter.

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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- Definition

Number of pending claims pertaining to a loss contingency.

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- Definition

Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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No definition available.

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Equity Method Investments - Equity Method Investment Reconciliation (Details) $ in Thousands, $ in Millions						3 Months Ended		9 Months Ended
	Jul. 26, 2016 USD ($)	May 02, 2016 installment suit	Dec. 09, 2015 USD ($)	Dec. 09, 2015 TWD ($)	Sep. 02, 2015 installment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2018 USD ($)
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity [Abstract]
Equity method investments						$ 12,861		$ 12,861		$ 12,016
Indemnification Agreement [Member] \| Equity Method Investments [Member] \| NEC TOKIN Corporation [Member]
Related Party Transactions [Abstract]
Litigation Settlement, Number of Payment Installments \| installment		5
Settled Litigation [Member] \| Indemnification Agreement [Member] \| Equity Method Investments [Member]
Related Party Transactions [Abstract]
Litigation Settlement, Payment Period					5 years
Litigation Settlement, Number of Payment Installments \| installment					6
Preliminary Settlement [Member] \| Indemnification Agreement [Member] \| Equity Method Investments [Member] \| NEC TOKIN Corporation [Member]
Related Party Transactions [Abstract]
Loss Contingency, Pending Claims, Number \| suit		2
TAIWAN, PROVINCE OF CHINA \| Taiwan, New Dollars
Related Party Transactions [Abstract]
Loss Contingency, Damages Sought, Value				$ 1,200.0
TAIWAN, PROVINCE OF CHINA \| Taiwan, New Dollars \| Minimum [Member]
Related Party Transactions [Abstract]
Loss Contingency, Damages Sought, Value				$ 609.1
TAIWAN, PROVINCE OF CHINA \| United States of America, Dollars
Related Party Transactions [Abstract]
Loss Contingency, Damages Sought, Value			$ 39,600
TAIWAN, PROVINCE OF CHINA \| United States of America, Dollars \| Minimum [Member]
Related Party Transactions [Abstract]
Loss Contingency, Damages Sought, Value			$ 19,800
BRAZIL \| United States of America, Dollars \| Settled Litigation [Member]
Related Party Transactions [Abstract]
Loss Contingency, Damages Paid, Value	$ 200
NT Sales Co., Ltd (NTS) [Member]
Related Party Transactions [Abstract]
Sales to NEC TOKIN						12,805	$ 12,837	37,402	$ 38,802
NEC TOKIN's sales to KEMET						$ 495	$ 278	$ 1,266	$ 1,002