LEASES - Other lease cost information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
LEASES
Cash paid for operating leases	$ 5,828	$ 3,023	$ 11,402	$ 5,914
Right-of-use assets obtained in exchange for operating lease liabilities	$ 2,270	$ 19,244	$ 24,478	$ 57,555
Weighted average remaining lease term (in years)	9 years 9 months 18 days	8 years 4 months 24 days	9 years 9 months 18 days	8 years 4 months 24 days
Weighted average discount rate	4.30%	3.80%	4.30%	3.80%