Business Segments - Schedule of Results of Operation, Depreciation and Amortization, Capital Expenditures and Total Assets by Reportable Segments (Details) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Jun. 30, 2025
Segment Reporting Information [Line Items]
Consolidated depreciation and amortization	$ 36.0	$ 33.8
Consolidated capital expenditures	42.6	26.9
Consolidated total assets	3,402.2		$ 3,486.8
Operating
Segment Reporting Information [Line Items]
Consolidated total assets	3,095.0		3,062.8
Corporate
Segment Reporting Information [Line Items]
Consolidated depreciation and amortization	1.2	1.3
Consolidated capital expenditures	0.7	0.3
Consolidated total assets	310.6		433.2
Intersegment
Segment Reporting Information [Line Items]
Consolidated total assets	(3.4)		(9.2)
Specialty Alloys Operations | Operating
Segment Reporting Information [Line Items]
Consolidated depreciation and amortization	30.4	28.6
Consolidated capital expenditures	38.9	20.5
Consolidated total assets	2,686.1		2,649.3
Performance Engineered Products | Operating
Segment Reporting Information [Line Items]
Consolidated depreciation and amortization	4.4	3.9
Consolidated capital expenditures	3.0	$ 6.1
Consolidated total assets	$ 408.9		$ 413.5