Long term debt and capital leases.

No definition available.

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Namespace Prefix:	kmt_
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- Definition

Long term debt and capital leases.

+ References

No definition available.

+ Details

Name:	kmt_LongTermDebtAndCapitalLeasesTextualAbstract
Namespace Prefix:	kmt_
Data Type:	xbrli:stringItemType
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- Definition

Fair value of the amount outstanding under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

+ Details

Name:	us-gaap_LineOfCreditFacilityFairValueOfAmountOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(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:	credit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=kmt_TwentyEighteenCreditAgreementMember
Namespace Prefix:
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Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jun. 30, 2019	Jun. 07, 2018
Long-Term Debt (Additional Textual) [Abstract]
Fixed rate at fair market value	$ 630.8	$ 622.0
2018 Credit Agreement [Member]
Long-Term Debt (Textual) [Abstract]
Borrowing outstanding under 2018 Credit Agreement	$ 0.0
Line of Credit Facility, Maximum Borrowing Capacity			$ 700.0