Pension and Other Postretirement and Postemployment Benefits (Details Textuals) (USD $)	12 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2009
Pension and Other Postretirement and Postemployment Benefits (Textuals) [Abstract]
Postretirement health care benefits are available to	employees and their spouses retiring on or after age 55 with 10 or more years of service
Special termination benefits due to an amendment of the plan			$ 2,651,000
Net periodic pension cost			6,938,000
Pension plans contribution [Member]
Pension and Other Postretirement and Postemployment Benefits (Textuals) [Abstract]
Special termination benefits due to an amendment of the plan	675,000	3,577,000
Accumulated benefit obligation for defined benefit plans	772,600,000	743,000,000
Net periodic pension cost	12,497,000	12,260,000	6,938,000
Increase in net periodic pension costs	200,000	5,400,000
Projected benefit payments in 2012	41,200,000
Projected benefit payments in 2013	41,400,000
Projected benefit payments in 2014	42,600,000
Projected benefit payments in 2015	44,700,000
Projected benefit payments in 2016	46,600,000
Projected benefit payments in 2017 through 2021	270,300,000
Amounts of accumulated other comprehensive loss expected to be recognized in net periodic pension cost during 2012 related to net actuarial losses	8,200,000
Amounts of accumulated other comprehensive loss expected to be recognized in net periodic pension cost during 2012 related to transition obligations	100,000
Amounts of accumulated other comprehensive loss expected to be recognized in net periodic pension cost during 2012 related to Prior service credit	200,000
Expected contribution by Employer in 2012	7,000,000
Other postretirement benefit plans [Member]
Pension and Other Postretirement and Postemployment Benefits (Textuals) [Abstract]
Special termination benefits due to an amendment of the plan	(524,000)
Net periodic pension cost	924,000	1,005,000	(1,312,000)
Projected benefit payments in 2012		2,400,000
Projected benefit payments in 2013		2,300,000
Projected benefit payments in 2014		2,300,000
Projected benefit payments in 2015		2,100,000
Projected benefit payments in 2016		2,100,000
Projected benefit payments in 2017 through 2021		8,600,000
Expected contribution by Employer in 2012		$ 2,100,000

Increase in net periodic pension costs.

Name:	kmt_IncreaseInNetPeriodicPensionCosts
Namespace Prefix:	kmt
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Pension and Other Postretirement and Postemployment Benefits Textuals.

+ Details

Name:	kmt_PensionAndOtherPostretirementAndPostemploymentBenefitsTextualsAbstract
Namespace Prefix:	kmt
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph e

+ Details

Name:	us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amounts in accumulated other comprehensive income related to gains and losses that are not recognized immediately and are expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph s

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 158
-Paragraph 7
-Subparagraph d

+ Details

Name:	us-gaap_DefinedBenefitPlanAmortizationOfNetGainsLosses
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amounts in accumulated other comprehensive income related to prior service cost or credit expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ References

+ Details

Name:	us-gaap_DefinedBenefitPlanAmortizationOfNetPriorServiceCostCredit
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amounts in accumulated other comprehensive income related to transition assets (obligations), origination from the adoption of FAS 87 and 106, expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ References

+ Details

Name:	us-gaap_DefinedBenefitPlanAmortizationOfNetTransitionAssetObligation
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph g

+ Details

Name:	us-gaap_DefinedBenefitPlanEstimatedFutureEmployerContributionsInNextFiscalYear
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of the aggregate benefits expected to be paid in the five fiscal years thereafter (the aggregate amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).

+ References