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Costs and Estimated Earnings in Excess of Billings - Costs and Estimated Earnings in Excess of Billings on Uncompleted Contracts (Detail) - USD ($) | Sep. 30, 2019 | Sep. 30, 2018
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Costs in Excess of Billings on Uncompleted Contracts or Programs [Abstract] |  |  |
Costs incurred on uncompleted contracts | $ 18,707,000 | $ 17,437,000 |
Estimated earnings | 9,063,000 | 7,335,000 |
Costs and estimated earnings on uncompleted contracts | 27,770,000 | 24,772,000 |
Billings to date | 13,932,000 | 12,872,000 |
Costs and estimated earnings in excess of billings | $ 13,838,000 | $ 11,900,000 | [1]
[1] | The amounts as of September 30, 2018 have been adjusted to reflect the change in inventory accounting method, as described in Notes 1 and 2 to the Consolidated Financial Statements.

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- Definition Amount billed to customers under long-term contracts or programs to be collected in the next rolling twelve months following the latest balance sheet. Excludes amounts due that have been withheld because of retainage provisions in a contract. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References No definition available. + Details
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