RESTRUCTURING CHARGES - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 3,891,000	$ 20,601,000	$ 13,247,000
Restructuring liability	3,763,000	1,578,000	9,483,000
Employee separation costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	3,891,000	16,852,000	13,247,000
Restructuring liability	3,763,000	$ 1,578,000	$ 9,483,000
2019 Cost Savings Initiative | Employee separation costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	3,900,000
2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 0