v3.26.1
Accumulated Other Comprehensive Loss - Components of and Changes in Accumulated Other Comprehensive (Loss) Income (Details) - USD ($)
$ in Thousands
 12 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2024
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]      
Beginning Balance $ 1,324,648 $ 1,288,599  
Ending Balance 1,613,437 1,324,648 $ 1,288,599
Pension and other postretirement benefits attributable to Kennametal      
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]      
Beginning Balance (223,016) (221,308) (215,435)
Other comprehensive income (loss) before reclassifications 6,479 (7,965) (10,100)
Amounts reclassified from AOCL 8,680 6,257 4,227
Net other comprehensive income (loss) 15,159 (1,708) (5,873)
Ending Balance (207,857) (223,016) (221,308)
Currency translation adjustment attributable to Kennametal      
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]      
Beginning Balance (165,859) (216,263) (202,641)
Other comprehensive income (loss) before reclassifications (26,733) 50,404 (13,622)
Amounts reclassified from AOCL 0 0 0
Net other comprehensive income (loss) (26,733) 50,404 (13,622)
Ending Balance (192,592) (165,859) (216,263)
Derivatives attributable to Kennametal      
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]      
Beginning Balance 2,182 2,983 3,733
Other comprehensive income (loss) before reclassifications (207) 771 (26)
Amounts reclassified from AOCL (556) (1,574) (725)
Net other comprehensive income (loss) (763) (803) (750)
Ending Balance 1,419 2,182 2,983
Total attributable to Kennametal      
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]      
Beginning Balance (386,693) (434,588) (414,343)
Other comprehensive income (loss) before reclassifications (20,461) 43,210 (23,748)
Amounts reclassified from AOCL 8,124 4,683 3,502
Net other comprehensive income (loss) (12,337) 47,893 (20,245)
Ending Balance (399,030) (386,693) (434,588)
Pension and other postretirement benefits attributable to noncontrolling interests      
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]      
Beginning Balance 0 0 0
Other comprehensive income (loss) before reclassifications 0 0 0
Net other comprehensive income (loss) 0 0 0
Ending Balance 0 0 0
Currency translation adjustment attributable to noncontrolling interests      
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]      
Beginning Balance (7,844) (8,680) (8,139)
Other comprehensive income (loss) before reclassifications (2,241) 836 (541)
Net other comprehensive income (loss) (2,241) 836 (541)
Ending Balance (10,085) (7,844) (8,680)
Derivatives attributable to noncontrolling interests      
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]      
Beginning Balance 0 0 0
Other comprehensive income (loss) before reclassifications 0 0 0
Net other comprehensive income (loss) 0 0 0
Ending Balance 0 0 0
Total attributable to noncontrolling interests      
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]      
Beginning Balance (7,844) (8,680) (8,139)
Other comprehensive income (loss) before reclassifications (2,241) 836 (541)
Net other comprehensive income (loss) (2,241) 836 (541)
Ending Balance $ (10,085) $ (7,844) $ (8,680)