Summary of Company's Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Revenue	$ 20,587	$ 21,270	$ 19,247	$ 14,644	$ 23,683	$ 14,195	$ 20,558	$ 15,285	$ 75,748	$ 73,721	$ 62,060
Income (loss) from operations	$ (780)	$ (5,136)	$ (5,222)	$ (9,605)	$ (18,178)	$ (13,774)	$ (11,060)	$ (11,311)	(20,743)	(54,323)	(55,510)
Depreciation, amortization, impairment, inventoryobsolescence and stock-based compensation expenses									21,656	50,300	37,538
Interest income									1,083	653	376
Interest expense									336	39	26
Operating Segments | Oil and Gas Markets
Segment Reporting Information [Line Items]
Revenue									44,951	47,109	33,792
Income (loss) from operations									(14,070)	(46,902)	(47,690)
Depreciation, amortization, impairment, inventoryobsolescence and stock-based compensation expenses									19,592	47,620	34,945
Interest income									614	311	161
Interest expense									2
Operating Segments | Adjacent Markets
Segment Reporting Information [Line Items]
Revenue									29,932	26,027	27,708
Income (loss) from operations									5,345	4,153	4,093
Depreciation, amortization, impairment, inventoryobsolescence and stock-based compensation expenses									654	785	746
Interest income											3
Operating Segments | Emerging Markets
Segment Reporting Information [Line Items]
Revenue									286
Income (loss) from operations									(718)
Depreciation, amortization, impairment, inventoryobsolescence and stock-based compensation expenses									207
Interest expense									1
Corporate
Segment Reporting Information [Line Items]
Revenue									579	585	560
Income (loss) from operations									(11,300)	(11,574)	(11,913)
Depreciation, amortization, impairment, inventoryobsolescence and stock-based compensation expenses									1,203	1,895	1,847
Interest income									469	342	212
Interest expense									$ 333	$ 39	$ 26