Details of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue	$ 23,683	$ 14,195	$ 20,558	$ 15,285	$ 16,314	$ 17,678	$ 14,931	$ 13,137	$ 73,721	$ 62,060	$ 84,867
United States
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue									60,696	56,094	77,487
Canada
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue									12,157	3,028	4,796
Colombia
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue									558	556	609
Russian Federation
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue									2,566	4,254	5,554
United Kingdom
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue									2,892	2,120	2,644
Eliminations
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue									$ (5,148)	$ (3,992)	$ (6,223)