Goodwill and Other Intangible Assets, Net - Narrative (Details)	3 Months Ended	12 Months Ended
	Dec. 31, 2020 USD ($)	Jun. 30, 2023 USD ($) reporting_unit	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Jun. 01, 2023	Jun. 01, 2022
Goodwill [Line Items]
Number of reporting units | reporting_unit		3
Goodwill		$ 241,400,000	$ 241,400,000	$ 241,400,000
Goodwill impairment	$ 52,800,000	0	0	52,800,000
Accumulated goodwill impairment loss		(134,600,000)	(134,600,000)	(134,600,000)
Amortization expense		6,800,000	6,900,000	6,900,000
Estimated annual amortization expense for 2024		6,600,000
Estimated annual amortization expense for 2025		6,500,000
Estimated annual amortization expense for 2026		6,500,000
Estimated annual amortization expense for 2027		4,600,000
Estimated annual amortization expense for 2028		800,000
Finite-lived intangible assets		$ 28,700,000	35,200,000
Special Alloy Operations Reporting Unit
Goodwill [Line Items]
Percentage of goodwill		81.00%
Reporting unit, percentage of fair value in excess of carrying amount					60.00%
Reporting unit, percentage of fair value in excess of carrying value if fair value reduced by one half percent					57.00%
Additive Reporting Unit | Technology Based Intangible Assets And Customer Relationships
Goodwill [Line Items]
Impairment of intangible assets				4,300,000
Facility Closing
Goodwill [Line Items]
Finite-lived intangible assets				0
Measurement Input, Terminal Growth Rate | Special Alloy Operations Reporting Unit
Goodwill [Line Items]
Reporting unit, long term growth rate reduction necessary to approximate net Book value						2.50%
Valuation Technique, Discounted Cash Flow | Measurement Input, Weighted Average Cost of Capital | Special Alloy Operations Reporting Unit
Goodwill [Line Items]
Goodwill, measurement input						11.00%
Valuation Technique, Discounted Cash Flow | Measurement Input, Terminal Growth Rate | Special Alloy Operations Reporting Unit
Goodwill [Line Items]
Goodwill, measurement input					0.50%
Performance Engineered Products
Goodwill [Line Items]
Number of reporting units | reporting_unit		2
Goodwill		$ 45,900,000	$ 45,900,000	$ 45,900,000
Performance Engineered Products | Dynamet
Goodwill [Line Items]
Goodwill		31,900,000
Reporting unit, percentage of fair value in excess of carrying amount					106.00%
Reporting unit, percentage of fair value in excess of carrying value if fair value reduced by one half percent					104.00%
Performance Engineered Products | Latrobe Distribution
Goodwill [Line Items]
Goodwill		$ 14,000,000
Reporting unit, percentage of fair value in excess of carrying value if fair value reduced by one half percent		10.00%			11.00%
Performance Engineered Products | Measurement Input, Terminal Growth Rate | Dynamet
Goodwill [Line Items]
Reporting unit, long term growth rate reduction necessary to approximate net Book value						2.50%
Performance Engineered Products | Measurement Input, Terminal Growth Rate | Latrobe Distribution
Goodwill [Line Items]
Reporting unit, long term growth rate reduction necessary to approximate net Book value		2.50%
Performance Engineered Products | Valuation Technique, Discounted Cash Flow | Measurement Input, Weighted Average Cost of Capital | Dynamet
Goodwill [Line Items]
Goodwill, measurement input						14.00%
Performance Engineered Products | Valuation Technique, Discounted Cash Flow | Measurement Input, Weighted Average Cost of Capital | Latrobe Distribution
Goodwill [Line Items]
Goodwill, measurement input					13.00%
Performance Engineered Products | Valuation Technique, Discounted Cash Flow | Measurement Input, Terminal Growth Rate | Dynamet
Goodwill [Line Items]
Goodwill, measurement input					0.50%
Performance Engineered Products | Valuation Technique, Discounted Cash Flow | Measurement Input, Terminal Growth Rate | Latrobe Distribution
Goodwill [Line Items]
Goodwill, measurement input		0.50%