RESTRUCTURING COSTS (Details) - 2017 Strategic Restructuring Plan - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2016
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2017	$ 1,579,000	$ 1,579,000
Adjustments		(72,000)
Non-cash activity		(39,000)
Cash payments		(1,468,000)
Balance as of December 31, 2018		0
Employee Separation Costs
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2017	1,522,000	1,522,000
Adjustments	44,000	(44,000)	$ 0
Non-cash activity		(10,000)
Cash payments		(1,468,000)
Balance as of December 31, 2018		0
Asset-Related Charges
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2017	0	0
Adjustments		0
Non-cash activity		0
Cash payments		0
Balance as of December 31, 2018		0
Other
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2017	$ 57,000	57,000
Adjustments		(28,000)
Non-cash activity		(29,000)
Cash payments		0
Balance as of December 31, 2018		$ 0