COMMITMENTS AND CONTINGENCIES - Supplemental Cash Flow and Other Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Operating cash flows from operating leases	$ 1,425	$ 1,145	$ 2,786	$ 2,159
Lease liabilities arising from obtaining right-of-use assets	$ 0	$ 0	$ 0	$ 2,941