LEASES - Future Operating Lease Commitments (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Maturities of lease liabilities
Three Months Ended December 31, 2019	$ 2,128
2020	8,357
2021	8,043
2022	7,339
2023	5,741
Thereafter	302
Total	31,910
Less imputed interest	(3,031)
Total	$ 28,879
Minimum cash basis operating lease commitments
2019		$ 7,700
2020		7,789
2021		7,450
2022		6,738
2023		5,200
Thereafter		90
Total		$ 34,967