LEASES - Maturities of operating lease liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019
Operating Lease Liabilities, Payments Due [Abstract]
One year	$ 10,720
Two years	10,425
Three years	9,995
Four years	10,118
Five years	9,039
Thereafter	44,587
Total undiscounted lease payments	94,884
Less: Present value discount	(16,085)
Lease Liability	$ 78,799	$ 85,100