Note 5 - Cost and Estimated Earnings on Uncompleted Contracts - Cost and Estimated Earnings on Uncompleted Contracts Included in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Costs and estimated earnings in excess of billings on uncompleted contracts	$ 52,198	$ 25,120
Billings in excess of costs and estimated earnings on uncompleted contracts	(31,630)	(33,892)
Total	$ 20,568
Total		$ (8,772)

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.

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Unbilled amounts due for 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 entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

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