Segment Reporting (Details) $ in Thousands	12 Months Ended
Sep. 30, 2023 USD ($) segment	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Segment Reporting
Number of Business Segment \| segment	1
Net revenues	$ 589,956	$ 490,461	$ 337,661
Long-lived assets	142,540	142,772
High Temperature Resistant Alloys [Member]
Segment Reporting
Net revenues	501,463	387,464	253,246
Corrosive Resistant Alloys [Member]
Segment Reporting
Net revenues	88,493	102,997	84,415
UNITED STATES
Segment Reporting
Net revenues	344,381	278,473	179,127
Long-lived assets	134,596	135,698
Europe
Segment Reporting
Net revenues	135,403	116,599	85,555
Long-lived assets	7,799	6,921
CHINA
Segment Reporting
Net revenues	27,097	33,910	30,668
Long-lived assets	145	153
Other Countries [Member]
Segment Reporting
Net revenues	$ 83,075	$ 61,479	$ 42,311

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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