RESTRUCTURING - Additional information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Restructuring Cost And Reserve [Line Items]
Accrued expenses	$ 11,666,000	$ 13,036,000
Accrued and unpaid liabilities	11,666,000	$ 13,036,000
2020 Restructuring Activities
Restructuring Cost And Reserve [Line Items]
Restructuring costs	700,000
2020 Restructuring Activities | Maximum
Restructuring Cost And Reserve [Line Items]
Accrued expenses	1,000,000.0
Accrued and unpaid liabilities	1,000,000.0
2019 Restructuring Activities
Restructuring Cost And Reserve [Line Items]
Restructuring costs	2,800,000
2019 Restructuring Activities | Maximum
Restructuring Cost And Reserve [Line Items]
Accrued expenses	100,000
Accrued and unpaid liabilities	$ 100,000