CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (5,047)	$ 247,876	$ 205,060
Unrealized (loss) gain on derivatives designated and qualified as cash flow hedges	(582)	197	(922)
Reclassification of unrealized loss on expired derivatives designated and qualified as cash flow hedges	679	1,348	3,747
Unrecognized net pension and other postretirement benefit loss	(18,299)	(39,639)	(5,991)
Reclassification of net pension and other postretirement benefit loss	7,935	5,124	7,274
Foreign currency translation adjustments	(35,891)	(20,785)	(1,490)
Other comprehensive (loss) income, net of tax	(46,158)	(53,755)	2,618
Total comprehensive (loss) income	(51,205)	194,121	207,678
Less: comprehensive (loss) income attributable to noncontrolling interests	1,846	(5,414)	(4,131)
Comprehensive (loss) income attributable to Kennametal Shareholders	$ (49,359)	$ 188,707	$ 203,547

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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