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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, 2022 | Sep. 30, 2021
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Costs in Excess of Billings on Uncompleted Contracts or Programs [Abstract] |  |
Costs incurred on uncompleted contracts | $ 12,660,000 | $ 11,483,000
Estimated earnings | 4,780,000 | 4,395,000
Costs and estimated earnings on uncompleted contracts | 17,440,000 | 15,878,000
Billings to date | 15,322,000 | 13,975,000
Costs and estimated earnings in excess of billings | $ 2,118,000 | $ 1,903,000

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