Summary of Significant Accounting Policies (Details Textual) (USD $)	12 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2009
Summary of Significant Accounting Policies (Additional Textuals) [Abstract]
Impairment chanrge for the indefinite lived trade mark	$ 10,800,000
Goodwill	511,328,000	489,443,000	502,983,000
Summary Of Significant Accounting Policies (Textuals) [Abstract]
Conditions for investments in entities accounted for an equity basis	Investments in entities of less than 50 percent of the voting stock over which we have significant influence are accounted for on an equity basis.
Conditions for investments in entities accounted for on the cost basis	Investments in entities of less than 50 percent of the voting stock in which we do not have significant influence are accounted for on the cost basis.
Excess and obsolete inventory reserve	55,300,000	68,300,000
Goodwill or intangible asset impairments	0	0
Intangible assets decreased due to foreign currency translation adjustments	8,500,000	6,000,000
Amortization expense for intangible assets	11,600,000	13,100,000	13,100,000
Estimated amortization expense for year 2012	10,800,000
Estimated amortization expense for year 2013	10,100,000
Estimated amortization expense for year 2014	9,800,000
Estimated amortization expense for year 2015	9,500,000
Estimated amortization expense for year 2016	9,100,000
Increase in weighted average shares due to increase due to dilutive effect of unexercised capital stock options, unvested restricted stock awards and unvested restricted stock units	1,100,000	700,000
Unexercised capital stock options, restricted stock units and restricted stock awards excluded from computation of diluted EPS	400,000	2,300,000	2,600,000
The conditions of shipment are considered to have occurred unless written notice of objection is received by Kennametal	within 10 calander days of the date specified on the invoice.
Termination of warranty	30 days after delivery of the product to the customer and does not apply to products that have been subjected to misuse, abuse, neglect or improper storage, handling or maintenance.
Exercisable period for capital stock options	10 years from the date of grant
Fair value of shares delivered	800,000	100,000	700,000
Research and development cost	33,300,000	28,000,000	27,600,000
Gains from foreign currency transactions included in other income	(6,600,000)	3,500,000	6,800,000
Computer hardware and software [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of Property, plant and equipment, Minimum	3
Estimated useful lives of Property, plant and equipment, Maximum	5
Building and improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of Property, plant and equipment, Minimum	15
Estimated useful lives of Property, plant and equipment, Maximum	40
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of Property, plant and equipment, Minimum	4
Estimated useful lives of Property, plant and equipment, Maximum	15
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives of Property, plant and equipment, Minimum	5
Estimated useful lives of Property, plant and equipment, Maximum	10
Industrial [Member]
Summary of Significant Accounting Policies (Additional Textuals) [Abstract]
Goodwill, Acquired During Period		700,000
Goodwill	261,103,000	243,132,000	255,784,000
Surface finishing machines and services business [Member]
Summary of Significant Accounting Policies (Additional Textuals) [Abstract]
Impairment losses			(37,300,000)
Engineered products business [Member]
Summary of Significant Accounting Policies (Additional Textuals) [Abstract]
Impairment losses			$ (62,900,000)
2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares available for issuance under stock and incentive plan	3,500,000
Summary Of Significant Accounting Policies (Textuals) [Abstract]
Aggregate number of shares available for issuance under stock and incentive plan	3,500,000