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RESTRUCTURING PLAN - Rollforward of Restructuring Reserve (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Restructuring Reserve [Roll Forward]
Beginning balance			$ 1,515,000
Additions	$ 100,000	$ 0	208,000	$ 0
Adjustments			39,000
Cash Payments			(1,385,000)
Ending balance	377,000		377,000
Retention
Restructuring Reserve [Roll Forward]
Beginning balance			935,000
Additions			192,000
Adjustments			37,000
Cash Payments			(972,000)
Ending balance	192,000		192,000
Severance and severance-related expenses
Restructuring Reserve [Roll Forward]
Beginning balance			580,000
Additions			16,000
Adjustments			2,000
Cash Payments			(413,000)
Ending balance	$ 185,000		$ 185,000