Selected Quarterly Financial Information (unaudited) (Summary of Selected Quarter Financial Information) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Segment Reporting [Abstract]
Revenue	$ 25,600	$ 22,376	$ 21,532	$ 22,490	$ 23,018	$ 21,194	$ 19,057	$ 18,416	$ 91,998	$ 81,685	$ 55,514
Cost of revenue	16,481	14,964	14,510	15,089	13,568	13,511	12,678	13,237	61,044	52,994	43,400
Gross profit	9,119	7,412	7,022	7,401	9,450	7,683	6,379	5,179	30,954	28,691	12,114
Operating expense (income):
Selling, general, and administrative	4,963	6,125	4,825	4,821	5,587	4,543	5,954	8,627	20,734	24,711	23,239
Research and development	2,392	2,405	2,564	2,560	2,649	2,274	2,022	2,174	9,921	9,119	9,306
Recovery of previously incurred litigation related fees and expenses from arbitration award	0	(2,599)	0	0					(2,599)	0	0
Gain from change in estimate on ARO obligation					0	0	0	(845)	0	(845)	0
(Gain) loss on sale of assets	0	(41)	0	0	0	0	0	228	(41)	228	(100)
Total operating expense	7,355	5,890	7,389	7,381	8,236	6,817	7,976	10,184	28,015	33,213	32,445
Operating income (loss)	1,764	1,522	(367)	20	1,214	866	(1,597)	(5,005)	2,939	(4,522)	(20,331)
Other income (expense):
Interest income (expense), net	48	32	25	(17)	36	4	165	(130)	88	75	(522)
Foreign exchange loss	(83)	(201)	25	(135)	(239)	50	(6)	57	(394)	(138)	(7)
Change in fair value of financial instruments					0	0	86	36	0	122	34
Total other (expense) income	(35)	(169)	50	(152)	(203)	54	245	(37)	(306)	59	(137)
Income (loss) from continuing operations before income tax (expense) benefit	1,729	1,353	(317)	(132)	1,011	920	(1,352)	(5,042)	2,633	(4,463)	(20,468)
Income tax (expense) benefit	8	(175)	155	(2)	339	(456)	396	1,912	(14)	2,191	24,550
Income (loss) from continuing operations	1,737	1,178	(162)	(134)	1,350	464	(956)	(3,130)	2,619	(2,272)	4,082
Income from discontinued operations, net of tax	259	123	4,144	1,121	130	1,976	4,008	59,258	5,647	65,372	770
Net income	$ 1,996	$ 1,301	$ 3,982	$ 987	$ 1,480	$ 2,440	$ 3,052	$ 56,128	$ 8,266	$ 63,100	$ 4,852
Per share data:
Net income (loss) per basic share, continuing operations, (in usd per share)	$ 0.07	$ 0.05	$ (0.01)	$ 0.00	$ 0.05	$ 0.02	$ (0.03)	$ (0.10)	$ 0.10	$ (0.08)	$ 0.13
Net income per basic share, discontinued operations (in usd per share)	0.01	0.00	0.16	0.04	0.01	0.06	0.13	1.90	0.22	2.18	0.03
Net income per basic share (in usd per share)	0.08	0.05	0.15	0.04	0.06	0.08	0.10	1.80	0.32	2.10	0.16
Net income (loss) per diluted share, continuing operations (in usd per share)	0.06	0.05	(0.01)	0.00	0.05	0.02	(0.03)	(0.10)	0.10	(0.08)	0.13
Net income per diluted share, discontinued operations (in usd per share)	0.01	0.00	0.16	0.04	0.01	0.06	0.13	1.90	0.21	2.18	0.03
Net income per diluted share (in usd per share)	$ 0.07	$ 0.05	$ 0.15	$ 0.04	$ 0.06	$ 0.08	$ 0.10	$ 1.80	$ 0.31	$ 2.10	$ 0.16
Weighted-average number of basic shares outstanding (in shares)	26,177	26,103	25,942	25,697	25,615	31,203	32,077	31,217	25,979	30,012	30,453
Weighted-average number of basic shares outstanding (in shares)	26,674	26,269	25,942	25,697	25,896	31,432	32,077	31,217	26,518	30,012	30,777