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Details of Revenue (Details) - USD ($) $ 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
Revenues From External Customers And Long Lived Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenue | $ 16,314 | $ 17,678 | $ 14,931 | $ 13,137 | $ 16,008 | $ 19,751 | $ 27,942 | $ 21,166 | $ 62,060 | $ 84,867 | $ 236,912
United States |  |  |  |  |  |  |  |  |  |  |
Revenues From External Customers And Long Lived Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  |  |  | 56,094 | 77,487 | 230,818
Canada |  |  |  |  |  |  |  |  |  |  |
Revenues From External Customers And Long Lived Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  |  |  | 3,028 | 4,796 | 39,064
Colombia |  |  |  |  |  |  |  |  |  |  |
Revenues From External Customers And Long Lived Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  |  |  | 556 | 609 | 3,222
Russian Federation |  |  |  |  |  |  |  |  |  |  |
Revenues From External Customers And Long Lived Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  |  |  | 4,254 | 5,554 | 14,048
United Kingdom |  |  |  |  |  |  |  |  |  |  |
Revenues From External Customers And Long Lived Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  |  |  | 2,120 | 2,644 | 2,229
Eliminations |  |  |  |  |  |  |  |  |  |  |
Revenues From External Customers And Long Lived Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenue |  |  |  |  |  |  |  |  | $ (3,992) | $ (6,223) | $ (52,469)

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