Second part of loan from Portuguese Government

No definition available.

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Namespace Prefix:	kem_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash outflow for the payment of debt classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=kem_PortugueseGovernmentLoan2Member
Namespace Prefix:
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Debt - Other (Details) € in Millions, ¥ in Millions, $ in Millions	1 Months Ended						3 Months Ended		66 Months Ended	96 Months Ended
	Feb. 28, 2019 EUR (€)	Feb. 28, 2019 USD ($)	Sep. 30, 2017 USD ($) Rate	Sep. 30, 2017 JPY (¥) Rate	Jul. 31, 2017 EUR (€)	Jul. 31, 2017 USD ($)	Mar. 31, 2018 EUR (€)	Mar. 31, 2018 USD ($)	Sep. 01, 2026 USD ($)	Feb. 01, 2025 EUR (€)	Feb. 01, 2025 USD ($)
Debt Instrument [Line Items]
Second part of loan					€ 0.3	$ 0.3
Other Debt Obligations
Debt Instrument [Line Items]
Proceeds from issuance of debt							€ 2.2	$ 2.5
Other Debt Obligations \| TOKIN
Debt Instrument [Line Items]
Proceeds from issuance of debt			$ 3.2	¥ 350.0
Debt Instrument, Basis Spread on Variable Rate			0.40%	0.40%
Stated interest rate (as a percent)			0.53%	0.53%
Other Debt Obligations \| Forecast
Debt Instrument [Line Items]
Repayments of other debt										€ 0.2	$ 0.2
Portuguese Government Loan 2 \| Other Debt Obligations
Debt Instrument [Line Items]
Proceeds from issuance of debt	€ 0.9	$ 1.1
Portuguese Government Loan 2 \| Other Debt Obligations \| Forecast
Debt Instrument [Line Items]
Repayments of other debt \| $									$ 0.1