Segment Reporting (Details) $ in Thousands	12 Months Ended
Sep. 30, 2022 USD ($) segment	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)
Segment Reporting
Number of Business Segment \| segment	1
Net revenues	$ 490,461	$ 337,661	$ 380,530
Long-lived assets	142,772	147,248
High Temperature Resistant Alloys [Member]
Segment Reporting
Net revenues	387,464	253,246	308,229
Corrosive Resistant Alloys [Member]
Segment Reporting
Net revenues	102,997	84,415	72,301
UNITED STATES
Segment Reporting
Net revenues	278,473	179,127	230,764
Long-lived assets	135,698	140,263
Europe
Segment Reporting
Net revenues	116,599	85,555	91,480
Long-lived assets	6,921	6,834
CHINA
Segment Reporting
Net revenues	33,910	30,668	17,398
Long-lived assets	153	151
Other Countries [Member]
Segment Reporting
Net revenues	$ 61,479	$ 42,311	$ 40,888

Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

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