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Summary of Revenue from the Sale of Products and Performance of Services Under Contracts with Customers Excludes All Revenue Earned from Rental Contracts by Operating Segments (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018
Disaggregation Of Revenue [Line Items] |  |
Total revenue | $ 45,847 | $ 53,306
Operating Segments |  |
Disaggregation Of Revenue [Line Items] |  |
Total revenue | 45,847 | 53,306
Operating Segments | Oil and Gas Markets Product and Services Revenue |  |
Disaggregation Of Revenue [Line Items] |  |
Total revenue | 15,628 | 23,179
Operating Segments | Oil and Gas Markets Product and Services Revenue | Traditional Exploration |  |
Disaggregation Of Revenue [Line Items] |  |
Total revenue | 8,712 | 11,795
Operating Segments | Oil and Gas Markets Product and Services Revenue | Wireless Exploration |  |
Disaggregation Of Revenue [Line Items] |  |
Total revenue | 4,362 | 6,851
Operating Segments | Oil and Gas Markets Product and Services Revenue | Reservoir |  |
Disaggregation Of Revenue [Line Items] |  |
Total revenue | 2,554 | 4,533
Operating Segments | Adjacent Markets Product and Services Revenue |  |
Disaggregation Of Revenue [Line Items] |  |
Total revenue | 30,060 | 29,841
Operating Segments | Adjacent Markets Product and Services Revenue | Industrial |  |
Disaggregation Of Revenue [Line Items] |  |
Total revenue | 18,324 | 18,352
Operating Segments | Adjacent Markets Product and Services Revenue | Imaging |  |
Disaggregation Of Revenue [Line Items] |  |
Total revenue | 11,736 | 11,489
Operating Segments | Emerging Markets Product and Services Revenue |  |
Disaggregation Of Revenue [Line Items] |  |
Total revenue | $ 159 | $ 286

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- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045 + Details
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