Selected Quarterly Data (Unaudited) - Schedule of Selected Unaudited Consolidated Quarterly Financial Information (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Selected Quarterly Data Unaudited [Abstract]
Revenue, net of returns and allowances	$ 20,174	$ 21,003	$ 20,633	$ 23,225	$ 23,079	$ 28,743	$ 21,115	$ 27,116	$ 85,035	$ 100,053	$ 83,073
Cost of sales	11,614	13,153	12,706	14,205	14,886	18,560	12,533	17,156	51,678	63,135	51,967
Gross profit	8,560	7,850	7,927	9,020	8,193	10,183	8,582	9,960	33,357	36,918	31,106
Selling, general and administrative	6,126	5,718	5,793	6,626	6,225	6,775	6,319	6,424	24,263	25,743	24,727
Research, development and engineering	743	746	713	866	821	582	778	675	3,068	2,856	2,738
Restructuring charges	38	35	173	864					1,110
Impairment charges					2,247
Operating income	1,653	1,351	1,248	664	(1,100)	2,826	1,485	2,861	4,916	6,072	3,641
Gain on sale of other assets						2,883				2,883
(Loss) income from equity method investment						232	28	(26)		234	(417)
Interest and other income (expense), net	341	249	96	166	342	410	(32)	18	852	738	379
Income from continuing operations before income taxes	1,994	1,600	1,344	830	(758)	6,351	1,481	2,853	5,768	9,927	3,603
Income tax provision	1,012	707	332	582	352	1,372	420	1,152	2,633	3,296	1,409
Income from continuing operations, net of tax	982	893	1,012	248	(1,110)	4,979	1,061	1,701	3,135	6,631	2,194
(Loss) income from discontinued operations, net of tax	(184)	1,154	(6,647)	(2,620)	(7,843)	(8)	1,774	4,751	(8,297)	(1,326)	5,892
Net (loss) income	$ 798	$ 2,047	$ (5,635)	$ (2,372)	$ (8,953)	$ 4,971	$ 2,835	$ 6,452	$ (5,162)	$ 5,305	$ 8,086
Gross margin	42.40%	37.40%	38.40%	38.80%	35.50%	35.40%	40.60%	36.70%
Operating margin	8.20%	6.40%	6.00%	2.90%	(4.80%)	9.80%	7.00%	10.60%
Income (Loss) Per Basic Share:
Basic income (loss) per share from continuing operations	$ 0.07	$ 0.06	$ 0.07	$ 0.02	$ (0.08)	$ 0.33	$ 0.07	$ 0.12	$ 0.22	$ 0.45	$ 0.16
Basic (loss) income per share from discontinued operations	(0.01)	0.08	(0.47)	(0.18)	(0.53)	0.00	0.12	0.32	(0.58)	(0.09)	0.52
Net income (loss) per basic share	0.06	0.14	(0.40)	(0.16)	(0.61)	0.33	0.19	0.44	(0.36)	0.36	0.68
Income (Loss) Per Diluted Share:
Diluted income (loss) per share from continuing operations	0.07	0.06	0.07	0.02	(0.08)	0.33	0.07	0.11	0.22	0.44	0.16
Diluted (loss) income per share from discontinued operations	(0.01)	0.08	(0.47)	(0.18)	(0.53)	0.00	0.12	0.31	(0.58)	(0.09)	0.52
Net income (loss) per diluted share	$ 0.06	$ 0.14	$ (0.40)	$ (0.16)	$ (0.61)	$ 0.33	$ 0.19	$ 0.42	$ (0.36)	$ 0.35	$ 0.68
Weighted average shares outstanding - basic	14,266	14,245	14,228	14,220	14,730	14,925	14,891	14,781	14,240	14,833	13,378
Weighted average shares outstanding - diluted	14,304	14,316	14,258	14,252	14,730	15,091	15,154	15,298	14,275	15,065	13,501