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Note 1 - Business Summary and Significant Accounting Policies (Details Textual)		3 Months Ended		6 Months Ended
	Apr. 03, 2017 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Number of Reportable Segments	2			2
Ownership Interest in Joint Venture				50.00%
Costs and Estimated Earnings in Excess of Billings [Member]
Contracts Receivable, Claims and Uncertain Amounts		$ 12,000,000		$ 12,000,000		$ 9,200,000
Contracts Receivable, Unpaid Project Contract Price		3,900,000		3,900,000		3,900,000
Unapproved Change Orders, Amount		1,400,000		1,400,000		$ 2,200,000
Operating Income (Loss) [Member]
Estimated Construction Gross (Loss) Profit, Before Tax		$ 1,800,000	$ 700,000	$ 1,100,000	$ (500,000)
Minimum [Member]
Ownership Interest in Joint Venture				50.00%
Revenue Recognition Percentage of Completion Range				12 years
Warranty Term				1 year
Maximum [Member]
Revenue Recognition Percentage of Completion Range				36 years
Warranty Term				2 years
Loan and Security Agreement [Member] | Wilmington Trust, National Association [Member] | Senior Secured Term Loans [Member]
Debt Instrument, Face Amount	$ 85,000,000
Tealstone Construction [Member]
Business Acquisition, Percentage of Voting Interests Acquired	100.00%

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- Definition

Amount of unpaid project contract price that the Company is entitled to.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Section S99
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The amount of costs incurred on unapproved change orders when it is probable that the cost will be recovered through a change in the contract price.

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-Name Accounting Standards Codification
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