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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
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Segment Reporting (Details) $ in Thousands	3 Months Ended								12 Months Ended
Segment Reporting (Details) $ in Thousands	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2017 USD ($) segment	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)
Segment Reporting
Number of Business Segment \| segment									1
Net revenues	$ 100,765	$ 97,977	$ 103,112	$ 93,355	$ 107,523	$ 101,255	$ 102,511	$ 95,070	$ 395,209	$ 406,359	$ 487,635
Long-lived assets	192,556				199,182				192,556	199,182
High-temperature resistant alloys
Segment Reporting
Net revenues									320,119	329,151	370,603
Corrosive-resistant alloys
Segment Reporting
Net revenues									75,090	77,208	117,032
United States
Segment Reporting
Net revenues									235,500	233,612	287,722
Long-lived assets	185,413				191,915				185,413	191,915
Europe
Segment Reporting
Net revenues									98,096	101,853	110,659
Long-lived assets	6,879				6,935				6,879	6,935
China
Segment Reporting
Net revenues									18,997	13,808	28,140
Long-lived assets	$ 264				$ 332				264	332
Other
Segment Reporting
Net revenues									$ 42,616	$ 57,086	$ 61,114