LEASES - Supplemental Balance Sheet Information (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Assets
Operating lease right-of-use assets	$ 58,657	$ 66,191	$ 67,296
Liabilities
Short-term operating lease liabilities	16,605	17,603	17,711
Long-term operating lease liabilities	41,324	$ 48,605	49,602
Total operating lease liabilities	$ 57,929		$ 67,313