Segment Information - Operating Segments (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2019
Segment Reporting Information [Line Items]
Sales	$ 16,095	$ 16,350	$ 32,667	$ 35,330
Sales:
Income (loss) from operations	(143)	(771)	(545)	(756)
Total assets	53,511	52,330	53,511	52,330	$ 59,369
Capital expenditures	33	37	240	268
Depreciation and amortization	114	100	239	206
High Performance Products Segment
Segment Reporting Information [Line Items]
Sales	1,475	1,614	2,516	3,640
Sales:
Income (loss) from operations	(1,024)	(1,093)	(2,287)	(1,920)
Total assets	8,685	12,583	8,685	12,583
Capital expenditures	29	37	63	240
Depreciation and amortization	57	55	115	108
TS
Segment Reporting Information [Line Items]
Sales	14,620	14,736	30,151	31,690
Sales:
Income (loss) from operations	881	322	1,742	1,164
Total assets	44,826	39,747	44,826	39,747
Capital expenditures	4		177	28
Depreciation and amortization	57	45	124	98
Product
Segment Reporting Information [Line Items]
Sales	12,296	13,603	25,518	29,314
Product \| High Performance Products Segment
Segment Reporting Information [Line Items]
Sales	922	1,375	1,689	3,108
Product \| TS
Segment Reporting Information [Line Items]
Sales	11,374	12,228	23,829	26,206
Service
Segment Reporting Information [Line Items]
Sales	3,799	2,747	7,149	6,016
Service \| High Performance Products Segment
Segment Reporting Information [Line Items]
Sales	553	239	827	532
Service \| TS
Segment Reporting Information [Line Items]
Sales	3,246	2,508	6,322	5,484
U.K. \| TS
Segment Reporting Information [Line Items]
Sales	268	1,983	947	3,785
Sales:
Income (loss) from operations	(50)	106	(47)	132
Total assets	10,757	13,222	10,757	13,222
Depreciation and amortization		1	3	3
U.K. \| Product \| TS
Segment Reporting Information [Line Items]
Sales	184	1,888	737	3,620
U.K. \| Service \| TS
Segment Reporting Information [Line Items]
Sales	84	95	210	165
U.S. \| TS
Segment Reporting Information [Line Items]
Sales	14,352	12,753	29,204	27,905
Sales:
Income (loss) from operations	931	216	1,789	1,032
Total assets	34,069	26,525	34,069	26,525
Capital expenditures	4		177	28
Depreciation and amortization	57	44	121	95
U.S. \| Product \| TS
Segment Reporting Information [Line Items]
Sales	11,190	10,340	23,092	22,586
U.S. \| Service \| TS
Segment Reporting Information [Line Items]
Sales	$ 3,162	$ 2,413	$ 6,112	$ 5,319

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