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Unbilled Receivables (Details) - USD ($) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2016 | Feb. 23, 2017
Unbilled Receivables |  |  |  |  |  |  |  |  |  |  |  |
Unbilled receivables, net of progress payments |  |  |  |  | $ 1,480,822 |  |  |  |  | $ 1,480,822 |  |
Cumulative change in operating income resulting from changes in estimates | $ (444,240) | $ (1,072,228) | $ (1,143,511) | $ (1,051,560) | $ (926,999) | $ (541,189) | $ 2,985,918 | $ (1,595,295) | $ (3,711,539) | (77,565) | $ 2,443,187 |
Long-term contracts accounted for under percentage-of-completion |  |  |  |  |  |  |  |  |  |  |  |
Unbilled Receivables |  |  |  |  |  |  |  |  |  |  |  |
Cumulative change in operating income resulting from changes in estimates |  |  |  |  |  |  |  |  | 0 | 61,000 | $ (58,000) |
Delta |  |  |  |  |  |  |  |  |  |  |  |
Unbilled Receivables |  |  |  |  |  |  |  |  |  |  |  |
Amount paid |  |  |  |  |  |  |  |  |  |  |  | $ 7,750,000
Delta | Selling, general and administrative expenses |  |  |  |  |  |  |  |  |  |  |  |
Unbilled Receivables |  |  |  |  |  |  |  |  |  |  |  |
Reversal of reserve |  |  |  |  |  |  |  |  | 3,600,000 |  |  |
Delta | Other income |  |  |  |  |  |  |  |  |  |  |  |
Unbilled Receivables |  |  |  |  |  |  |  |  |  |  |  |
Reminder of amount paid |  |  |  |  |  |  |  |  | $ 4,100,000 | $ 4,100,000 |  |

X
- Definition Amount paid towards reversal of reserve and collection of the unbilled receivables. + References No definition available. + Details
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- Definition The remaining amount paid after reversal of reserve. + References No definition available. + Details
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- Definition Amount of reversal of reserves created under unbilled receivables. + References No definition available. + 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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- Definition Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer. + References No definition available. + Details
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- Details
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- Details
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