Line of Credit, Covenant Compliance, Pledged Percent of Outstanding Voting Stock

No definition available.

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Balance Type:	na
Period Type:	instant

- Definition

Line of Credit, Debt Issue Discount Percent

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Line of Credit Facility, Maximum Borrowing Capacity, Incremental Increase

+ References

No definition available.

+ Details

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

- Definition

Line of Credit Facility, Periodic Payment, Percent

+ References

No definition available.

+ Details

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Balance Type:	na
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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Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the required periodic payments of both interest and principal.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

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Period Type:

- Details

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- Details

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- Details

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- Details

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- Details

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Subsequent Events - Long-term debt (Details) - USD ($)	Apr. 28, 2017	Mar. 31, 2017	Dec. 31, 2016	May 05, 2010
Term Loan Credit Agreement \| Line of Credit \| Subsequent Event
Subsequent Event [Line Items]
Maximum borrowing capacity	$ 345,000,000
Incremental commitments	$ 50,000,000
Stated interest rate (as a percent)	0.97%
Discount bps	3.00%
Percent of outstanding voting stock	65.00%
Percent of aggregate principal	1.25%
Payment amount	$ 4,300,000
Loan Amendment \| Line of Credit \| Subsequent Event
Subsequent Event [Line Items]
Maximum borrowing capacity	$ 75,000,000
10.5% Senior Notes
Subsequent Event [Line Items]
Stated interest rate (as a percent)		10.50%	10.50%	10.50%
Base Rate \| Term Loan Credit Agreement \| Line of Credit \| Subsequent Event
Subsequent Event [Line Items]
Spread on variable rate basis (as a percent)	5.00%
LIBOR \| Term Loan Credit Agreement \| Line of Credit \| Subsequent Event
Subsequent Event [Line Items]
Spread on variable rate basis (as a percent)	6.00%
Minimum \| LIBOR \| Term Loan Credit Agreement \| Line of Credit \| Subsequent Event
Subsequent Event [Line Items]
Spread on variable rate basis (as a percent)	1.00%