Pension and Other Postretirement Benefits - Narrative (Details) - Pension Plans - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions	$ 5.9	$ 9.6
Expected contributions for next fiscal year	$ 17.6

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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CARPENTER TECHNOLOGY CORP 10-Q