Note 3 - Contracts in Progress - Costs, Estimated Earnings, and Billings on Uncompleted Contracts (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Costs incurred on contracts in progress	$ 24,913,254	$ 22,079,680
Estimated earnings	26,040,219	16,499,697
	50,953,473	38,579,377
Billings to date	(50,132,200)	(30,648,666)
	821,273	(7,930,711)
Included in accompanying balance sheets
Contract assets	1,357,797	8,397,024
Contract liabilities	$ (536,524)	$ (466,313)

Amount billed to customers on uncompleted contracts.

No definition available.

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Amount of revenue recognized on uncompleted contracts as a result of the actual costs incurred compared to estimated total costs.

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Those actual material, labor and overhead costs incurred on all uncompleted contracts.

+ References

No definition available.

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Estimated earnings on the amount of revenue recognized as a result of the actual costs incurred compared to the estimated total costs of the contract.

+ References

No definition available.

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Recognition of additional revenue in excess of that billed as a result of actual costs incurred.

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No definition available.

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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.

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

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