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, 2024	Sep. 30, 2023	Jun. 30, 2024
Net Sales
Total net sales	$ 717.6	$ 651.9
Operating Income (Loss)
Consolidated operating income	113.6	69.0
Depreciation and Amortization
Consolidated depreciation and amortization	33.8	33.1
Capital Expenditures
Consolidated capital expenditures	26.9	22.0
Total Assets
Consolidated total assets	3,255.0		$ 3,291.7
Operating | Specialty Alloys Operations
Net Sales
Total net sales	645.1	570.1
Operating Income (Loss)
Consolidated operating income	134.5	80.8
Depreciation and Amortization
Consolidated depreciation and amortization	28.6	27.8
Capital Expenditures
Consolidated capital expenditures	20.5	18.6
Total Assets
Consolidated total assets	2,567.6		2,542.2
Operating | Performance Engineered Products
Net Sales
Total net sales	100.8	101.8
Operating Income (Loss)
Consolidated operating income	7.3	9.1
Depreciation and Amortization
Consolidated depreciation and amortization	3.9	4.0
Capital Expenditures
Consolidated capital expenditures	6.1	3.2
Total Assets
Consolidated total assets	430.7		431.5
Corporate
Operating Income (Loss)
Consolidated operating income	(28.0)	(21.3)
Depreciation and Amortization
Consolidated depreciation and amortization	1.3	1.3
Capital Expenditures
Consolidated capital expenditures	0.3	0.2
Total Assets
Consolidated total assets	270.1		334.8
Intersegment
Net Sales
Total net sales	(28.3)	(20.0)
Operating Income (Loss)
Consolidated operating income	(0.2)	$ 0.4
Total Assets
Consolidated total assets	$ (13.4)		$ (16.8)