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
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-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, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2018 USD ($) segment	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)
Segment Reporting
Number of Business Segment \| segment									1
Net revenues	$ 122,313	$ 113,114	$ 110,206	$ 89,693	$ 100,765	$ 97,977	$ 103,112	$ 93,355	$ 435,326	$ 395,209	$ 406,359
Long-lived assets	179,400				192,556				179,400	192,556
High-temperature resistant alloys
Segment Reporting
Net revenues									352,614	320,119	329,151
Corrosive-resistant alloys
Segment Reporting
Net revenues									82,712	75,090	77,208
U.S. pension plan
Segment Reporting
Net revenues									258,275	235,500	233,612
Long-lived assets	172,689				185,413				172,689	185,413
Europe
Segment Reporting
Net revenues									113,967	98,096	101,853
Long-lived assets	6,522				6,879				6,522	6,879
China
Segment Reporting
Net revenues									24,640	18,997	13,808
Long-lived assets	$ 189				$ 264				189	264
Other
Segment Reporting
Net revenues									$ 38,444	$ 42,616	$ 57,086