REVENUE (Tables)

3 Months Ended

Mar. 31, 2018

			Contract Liabilities
	Accounts Receivable, net (1)		Billings in Excess of Costs and Estimated Earnings on Uncompleted Contracts (1)			Deferred Revenue (1) (current)		Deferred Revenue (1) (non-current)
Balance as of March 31, 2018	$	695,900	$	213,900		$	325,400	$	87,900
Balance as of December 31, 2017		692,400		227,300			304,200		113,100
Increase (decrease)	$	3,500	($	13,400	)	$	21,200	($	25,200	)