Reportable Segments - Schedule of Reportable Segment Information (Details) - USD ($) $ in Thousands		3 Months Ended			6 Months Ended
		Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2023	Mar. 31, 2022	Sep. 30, 2022
Segment Reporting Information [Line Items]
Net Revenues		$ 33,310	$ 27,556	$ 26,463	$ 54,868	$ 54,019
Operating income (loss)		519	2,595		(2,161)	3,835
Identifiable Assets		151,002			151,002		$ 133,534
Operating Segments | Semiconductor
Segment Reporting Information [Line Items]
Net Revenues		22,047	23,584		38,934	46,349
Operating income (loss)		2,950	3,368		3,819	5,725
Identifiable Assets		75,879			75,879		75,622
Operating Segments | Material and Substrate
Segment Reporting Information [Line Items]
Net Revenues		11,263	3,972		15,934	7,670
Operating income (loss)		297	654		930	835
Identifiable Assets		70,143			70,143		22,032
Non-Segment Related
Segment Reporting Information [Line Items]
Operating income (loss)		(2,728)	$ (1,427)		(6,910)	$ (2,725)
Identifiable Assets	[1]	$ 4,980			$ 4,980		$ 35,880

[1] * Non-segment related assets include cash, property, and other assets.