Revenue - Summary of Revenues by End-Use Markets and Geography (Details) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Total net sales	$ 651.9	$ 522.9
Intersegment
Disaggregation of Revenue [Line Items]
Total net sales	(20.0)	(17.6)
United States
Disaggregation of Revenue [Line Items]
Total net sales	393.3	319.6
United States | Intersegment
Disaggregation of Revenue [Line Items]
Total net sales	(5.7)	(7.2)
Europe
Disaggregation of Revenue [Line Items]
Total net sales	107.4	90.8
Europe | Intersegment
Disaggregation of Revenue [Line Items]
Total net sales	(4.3)	(3.9)
Asia Pacific
Disaggregation of Revenue [Line Items]
Total net sales	103.0	58.1
Asia Pacific | Intersegment
Disaggregation of Revenue [Line Items]
Total net sales	(10.1)	(6.5)
Mexico
Disaggregation of Revenue [Line Items]
Total net sales	24.2	33.0
Mexico | Intersegment
Disaggregation of Revenue [Line Items]
Total net sales	0.0	0.0
Canada
Disaggregation of Revenue [Line Items]
Total net sales	13.7	11.7
Canada | Intersegment
Disaggregation of Revenue [Line Items]
Total net sales	(0.1)	0.1
Other
Disaggregation of Revenue [Line Items]
Total net sales	10.3	9.7
Other | Intersegment
Disaggregation of Revenue [Line Items]
Total net sales	0.2	(0.1)
Aerospace and Defense
Disaggregation of Revenue [Line Items]
Total net sales	352.5	261.6
Aerospace and Defense | Intersegment
Disaggregation of Revenue [Line Items]
Total net sales	(5.0)	(5.7)
Medical
Disaggregation of Revenue [Line Items]
Total net sales	80.0	59.2
Medical | Intersegment
Disaggregation of Revenue [Line Items]
Total net sales	(11.0)	(6.3)
Transportation
Disaggregation of Revenue [Line Items]
Total net sales	42.0	36.9
Transportation | Intersegment
Disaggregation of Revenue [Line Items]
Total net sales	0.0	(0.1)
Energy
Disaggregation of Revenue [Line Items]
Total net sales	44.7	27.9
Energy | Intersegment
Disaggregation of Revenue [Line Items]
Total net sales	0.0	(0.1)
Industrial and Consumer
Disaggregation of Revenue [Line Items]
Total net sales	105.0	105.0
Industrial and Consumer | Intersegment
Disaggregation of Revenue [Line Items]
Total net sales	(4.0)	(5.4)
Distribution
Disaggregation of Revenue [Line Items]
Total net sales	27.7	32.3
Distribution | Intersegment
Disaggregation of Revenue [Line Items]
Total net sales	0.0	0.0
Specialty Alloys Operations
Disaggregation of Revenue [Line Items]
Total net sales	570.1	447.3
Specialty Alloys Operations | United States
Disaggregation of Revenue [Line Items]
Total net sales	340.7	271.3
Specialty Alloys Operations | Europe
Disaggregation of Revenue [Line Items]
Total net sales	94.9	78.9
Specialty Alloys Operations | Asia Pacific
Disaggregation of Revenue [Line Items]
Total net sales	102.7	57.6
Specialty Alloys Operations | Mexico
Disaggregation of Revenue [Line Items]
Total net sales	14.4	22.2
Specialty Alloys Operations | Canada
Disaggregation of Revenue [Line Items]
Total net sales	9.3	8.7
Specialty Alloys Operations | Other
Disaggregation of Revenue [Line Items]
Total net sales	8.1	8.6
Specialty Alloys Operations | Aerospace and Defense
Disaggregation of Revenue [Line Items]
Total net sales	332.2	246.6
Specialty Alloys Operations | Medical
Disaggregation of Revenue [Line Items]
Total net sales	55.3	40.9
Specialty Alloys Operations | Transportation
Disaggregation of Revenue [Line Items]
Total net sales	40.1	35.9
Specialty Alloys Operations | Energy
Disaggregation of Revenue [Line Items]
Total net sales	43.2	26.6
Specialty Alloys Operations | Industrial and Consumer
Disaggregation of Revenue [Line Items]
Total net sales	99.3	97.3
Specialty Alloys Operations | Distribution
Disaggregation of Revenue [Line Items]
Total net sales	0.0	0.0
Performance Engineered Products
Disaggregation of Revenue [Line Items]
Total net sales	101.8	93.2
Performance Engineered Products | United States
Disaggregation of Revenue [Line Items]
Total net sales	58.3	55.5
Performance Engineered Products | Europe
Disaggregation of Revenue [Line Items]
Total net sales	16.8	15.8
Performance Engineered Products | Asia Pacific
Disaggregation of Revenue [Line Items]
Total net sales	10.4	7.0
Performance Engineered Products | Mexico
Disaggregation of Revenue [Line Items]
Total net sales	9.8	10.8
Performance Engineered Products | Canada
Disaggregation of Revenue [Line Items]
Total net sales	4.5	2.9
Performance Engineered Products | Other
Disaggregation of Revenue [Line Items]
Total net sales	2.0	1.2
Performance Engineered Products | Aerospace and Defense
Disaggregation of Revenue [Line Items]
Total net sales	25.3	20.7
Performance Engineered Products | Medical
Disaggregation of Revenue [Line Items]
Total net sales	35.7	24.6
Performance Engineered Products | Transportation
Disaggregation of Revenue [Line Items]
Total net sales	1.9	1.1
Performance Engineered Products | Energy
Disaggregation of Revenue [Line Items]
Total net sales	1.5	1.4
Performance Engineered Products | Industrial and Consumer
Disaggregation of Revenue [Line Items]
Total net sales	9.7	13.1
Performance Engineered Products | Distribution
Disaggregation of Revenue [Line Items]
Total net sales	$ 27.7	$ 32.3