LEASES - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Leases [Abstract]
Cash paid for amounts included in the measurement of operating lease liabilities			$ 4,692	$ 5,404
Right-of-use assets acquired under operating lease			1,088	915
Operating lease expense	$ 848	$ 1,006	2,700	3,946
Short-term lease expense	1,033	1,077	2,523	4,373
Variable and other lease costs	$ 419	$ 444	$ 1,638	$ 1,490