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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)

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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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