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Costs and Estimated Earnings on Uncompleted Contracts (Tables) | 12 Months Ended
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Dec. 31, 2017
Contractors [Abstract] |
Schedule of Cost and Estimated Earnings on Uncompleted Contracts | Uncompleted contracts were as follows (in thousands):
|  | As of December 31, 2017 |
Costs incurred on uncompleted contracts |  | $ | 79,235 |
Estimated earnings |  |  | 44,035 |
Total |  |  | 123,270 |
Less: Billings to date |  |  | 121,464 |
Net under (over) billings |  | $ | 1,806 |
Schedule of Net Under (Over) Billings | Net under (over) billings were as follows (in thousands):
|  | As of December 31, 2017 |
Costs and estimated earnings in excess of billings on uncompleted contracts |  | $ | 6,182 |
Billings in excess of costs and estimated earnings on uncompleted contracts |  |  | (4,376 | )
Net under (over) billings |  | $ | 1,806 |

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