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Note 4 - Cost and Estimated Earnings in Excess of Billings on Uncompleted Contracts and Billings in Excess of Costs and Estimated Earnings (Tables) | 12 Months Ended
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Dec. 31, 2017
Notes Tables |
Schedule of Costs and Estimated Earnings in Excess of Billings on Uncompleted Contracts and Billings in Excess of Costs and Estimated Earnings [Table Text Block] |
|  | December 31 , |
|  | 201 7 |  |  | 201 6 |
|  | (in thousands ) |
Costs incurred on uncompleted contract s |  | $ | 227,048 |  |  | $ | 238,050 |
Estimated earning s |  |  | 9,722 |  |  |  | 7,247 |
|  |  | 236,770 |  |  |  | 245,297 |
Less billings to dat e |  |  | (194,867 | ) |  |  | (203,672 | )
|  | $ | 41,903 |  |  | $ | 41,625 |
Amounts are presented in the Consolidated Balance Sheets as follows : |  |  |  |  |  |  |  |
Costs and estimated earnings in excess of billings on uncompleted contract s |  | $ | 44,502 |  |  | $ | 43,663 |
Billings in excess of costs and estimated earnings on uncompleted contract s |  |  | (2,599 | ) |  |  | (2,038 | )
|  | $ | 41,903 |  |  | $ | 41,625 |

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- Definition Tabular disclosure of costs and estimated earnings in excess of billings on uncompleted contracts and billings in excess of costs and estimated earnings. + References No definition available. + Details
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Balance Type: | na
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- References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration