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Costs and Estimated Earnings and Billings on Uncompleted Contracts (Tables) | 12 Months Ended
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Dec. 31, 2017
Contractors [Abstract] |
Schedule of Excess Billings Over Earnings | The two tables below set forth the costs incurred and earnings accrued on uncompleted contracts (revenues) compared with the billings on those contracts through December 31, 2017 and 2016 and reconcile the net excess billings to the amounts included in the consolidated balance sheets at those dates (amounts in thousands).
| As of December 31,
| 2017 |  | 2016
Costs incurred and estimated earnings on uncompleted contracts | $ | 2,380,866 |  |  | $ | 1,749,328 |
Billings on uncompleted contracts | (2,406,128 | ) |  | (1,780,723 | )
Excess of billings over costs incurred and estimated earnings | $ | (25,262 | ) |  | $ | (31,395 | )
Schedule of Net Amount of Costs and Earnings on Uncompleted Contracts | Included in the accompanying balance sheets under the following captions:
| As of December 31,
| 2017 |  | 2016
Costs and estimated earnings in excess of billings on uncompleted contracts | $ | 37,112 |  |  | $ | 32,705 |
Billings in excess of costs and estimated earnings on uncompleted contracts | (62,374 | ) |  | (64,100 | )
Net amount of costs and estimated earnings on uncompleted contracts below billings | $ | (25,262 | ) |  | $ | (31,395 | )

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