Condensed Consolidated Statements of Operations and Comprehensive (Loss) Income (unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Revenue	$ 17,717	$ 30,952	$ 60,376	$ 93,719
Cost of revenue	16,519	20,110	46,317	61,796
Gross profit	1,198	10,842	14,059	31,923
Operating expense (income):
Selling, general, and administrative	5,237	5,815	15,700	17,065
Research and development	3,915	3,340	11,015	8,680
Impairments	0	0	0	468
(Gain) loss on sale of assets	0	(322)	39	(322)
Total operating expense	9,152	8,833	26,754	25,891
Operating (loss) income	(7,954)	2,009	(12,695)	6,032
Other income (expense):
Interest income, net	216	77	490	146
Foreign exchange (loss) gain	(676)	53	136	(306)
Other income	0	316	0	316
Total other (expense) income	(460)	446	626	156
(Loss) income from continuing operations before income tax benefit (expense)	(8,414)	2,455	(12,069)	6,188
Income tax benefit (expense)	0	(19)	502	(131)
(Loss) income from continuing operations	(8,414)	2,436	(11,567)	6,057
Loss from discontinued operations, net of tax	0	(11)	0	(27)
Net (loss) income	(8,414)	2,425	(11,567)	6,030
Foreign exchange translation adjustment	(54)	(1)	320	15
Comprehensive (loss) income	$ (8,468)	$ 2,424	$ (11,247)	$ 6,045
Net (loss) income per basic share:
Continuing operations (in usd per share)	$ (0.31)	$ 0.09	$ (0.43)	$ 0.23
Discontinued operations (in usd per share)	0.00	0.00	0.00	0.00
Net (loss) income per basic share (in usd per share)	(0.31)	0.09	(0.43)	0.23
Net (loss) income per diluted share:
Continuing operations (in usd per share)	(0.31)	0.09	(0.43)	0.22
Discontinued operations (in usd per share)	0.00	0.00	0.00	0.00
Net income per diluted share (in usd per share)	$ (0.31)	$ 0.09	$ (0.43)	$ 0.22
Weighted-average number of basic shares outstanding (in shares)	27,387	26,833	27,204	26,577
Weighted-average number of basic shares outstanding (in shares)	27,387	27,816	27,204	27,548