Uncompleted Contracts (Tables)

9 Months Ended

Sep. 30, 2020

Costs, estimated earnings and billings on uncompleted contracts are as follows:

	September 30,			December 31,
	2020			2019

Revenue recognized	$	1,387,800		$	1,074,800
Less: billings to date		(1,078,200	)		(832,300	)
Costs and estimated earnings in excess of billings on uncompleted contracts		309,600			242,500
Billings to date		576,700			2,707,200
Revenue recognized		(264,600	)		(2,380,100	)
Revenue contract liabilities	$	312,100		$	327,100