Summary of Company's Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting Information [Line Items]
Revenue	$ 21,270	$ 14,195	$ 55,161	$ 50,038
Income (loss) from operations	(5,136)	(13,774)	(19,963)	(36,145)
Operating Segments | Seismic
Segment Reporting Information [Line Items]
Revenue	12,345	7,308	31,671	30,658
Income (loss) from operations	(4,122)	(11,972)	(15,552)	(30,581)
Operating Segments | Non-Seismic
Segment Reporting Information [Line Items]
Revenue	8,778	6,741	23,058	18,945
Income (loss) from operations	1,428	1,004	3,841	3,108
Corporate
Segment Reporting Information [Line Items]
Revenue	147	146	432	435
Income (loss) from operations	$ (2,442)	$ (2,806)	$ (8,252)	$ (8,672)