Segment Information - Operating Segments (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Sep. 30, 2020
Segment Reporting Information [Line Items]
Total sales	$ 11,388	$ 16,858
Sales:
Income (loss) from operations	(537)	(402)
Total assets	53,037	56,248	$ 53,645
Capital expenditures	33	207
Depreciation and amortization	104	125
High Performance Products Segment
Segment Reporting Information [Line Items]
Total sales	1,556	1,041
Sales:
Income (loss) from operations	(854)	(1,263)
Total assets	9,192	10,496
Capital expenditures	6	34
Depreciation and amortization	48	58
TS
Segment Reporting Information [Line Items]
Total sales	9,832	15,817
Sales:
Income (loss) from operations	317	861
Total assets	43,845	45,752
Capital expenditures	27	173
Depreciation and amortization	56	67
Product
Segment Reporting Information [Line Items]
Total sales	8,408	13,559
Product \| High Performance Products Segment
Segment Reporting Information [Line Items]
Total sales	1,176	767
Product \| TS
Segment Reporting Information [Line Items]
Total sales	7,232	12,792
Service
Segment Reporting Information [Line Items]
Total sales	2,980	3,299
Service \| High Performance Products Segment
Segment Reporting Information [Line Items]
Total sales	380	274
Service \| TS
Segment Reporting Information [Line Items]
Total sales	2,600	3,025
U.K. \| TS
Segment Reporting Information [Line Items]
Total sales	1,490	679
Sales:
Income (loss) from operations	31	3
Total assets	10,675	10,847
Depreciation and amortization		3
U.K. \| Product \| TS
Segment Reporting Information [Line Items]
Total sales	1,403	553
U.K. \| Service \| TS
Segment Reporting Information [Line Items]
Total sales	87	126
U.S. \| TS
Segment Reporting Information [Line Items]
Total sales	8,342	15,138
Sales:
Income (loss) from operations	286	858
Total assets	33,170	34,905
Capital expenditures	27	173
Depreciation and amortization	56	64
U.S. \| Product \| TS
Segment Reporting Information [Line Items]
Total sales	5,829	12,239
U.S. \| Service \| TS
Segment Reporting Information [Line Items]
Total sales	$ 2,513	$ 2,899

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