Note 2 - Summary of Significant Accounting Policies - Impact on Previously Reported Results (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Costs and estimated earnings in excess of billings
Contract assets	$ 1,357,797	8,397,024
Billings in excess of costs and estimated earnings
Contract liabilities	$ 536,524	466,313
Previously Reported [Member]
Costs and estimated earnings in excess of billings		8,397,000
Contract assets
Billings in excess of costs and estimated earnings		466,000
Contract liabilities
Restatement Adjustment [Member] \| Accounting Standards Update 2014-09 [Member]
Costs and estimated earnings in excess of billings		(8,397,000)
Contract assets		8,397,000
Billings in excess of costs and estimated earnings		(466,000)
Contract liabilities		$ 466,000

Represents the 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.

No definition available.

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Represents the 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.

+ References

No definition available.

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

+ References

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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