Contracts in Progress (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Contractors [Abstract]
Costs incurred on uncompleted contracts	$ 606,035,000	$ 554,109,000
Estimated earnings	98,788,000	97,687,000
Costs incurred and estimated earnings on uncompleted contracts	704,823,000	651,796,000
Less: Billings to date	(666,871,000)us-gaap_BilledContractReceivables	(623,919,000)us-gaap_BilledContractReceivables
Costs and estimated earnings in excess of billings on uncompleted contracts, net	37,952,000	27,877,000
Costs and estimated earnings in excess of billings on uncompleted contracts	47,104,000	44,581,000
Billings in excess of costs and estimated earnings on uncompleted contracts	(9,152,000)us-gaap_BillingsInExcessOfCostCurrent	(16,704,000)us-gaap_BillingsInExcessOfCostCurrent
Costs incurred on completed contracts	$ 900,000

Costs in Excess of Billings on Uncompleted Contracts, Net

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Inventory for Long-term Contracts or Programs, Costs Incurred on Uncompleted Contracts

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Inventory for Long-term Contracts or Programs, Estimated Earnings on Uncompleted Contracts

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orn CostsincurredonCompleted contracts

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Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

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Liability attributable to (i) billings in excess of costs under the percentage of completion contract accounting method representing the difference between contractually invoiced amounts (billings) and revenue recognized based, for example, on costs incurred to estimated total costs at period end or (ii) contractually invoiced amounts (billings) in excess of costs incurred and accumulated under the completed contract accounting method that are expected to be realized within one year or one operating cycle, whichever is longer, from the reporting date.

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Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings which is expected to be collected within one year or the normal operating cycle, if longer.

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Amount before valuation and LIFO reserves, and progress payments, of inventory associated with long-term contracts, expected to be sold, or consumed within one year or operating cycle, if longer.

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