Note 3 - Contracts in Progress - Costs, Estimated Earnings, and Billings on Uncompleted Contracts (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Costs incurred on contracts in progress	$ 6,943,067	$ 24,913,254
Estimated earnings	3,370,032	26,040,219
	10,313,099	50,953,473
Billings to date	(10,645,800)	(50,132,200)
	(332,701)	821,273
Included in accompanying balance sheets
Contract assets	512,952	1,357,797
Contract liabilities	$ (845,653)	$ (536,524)