SEGMENT REPORTING - Reconciliation of Operating Income to Consolidated Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Adjustment for:
Amortization of intangible assets			$ 7,617	$ 8,477
Income from operations	$ 22,847	$ 20,060	37,663	31,209
Interest expense	4,885	6,137	9,925	11,178
Other income, net	185	(1,416)	152	(1,438)
Income before income taxes	17,777	15,339	27,586	21,469
Operating Segments
Segment Reporting Information, Operating Income (Loss) [Abstract]
Operating income for reportable segments	39,042	35,144	68,907	61,409
Segment Reconciling Items
Adjustment for:
Amortization of intangible assets	3,803	4,119	7,617	8,477
Corporate
Adjustment for:
Corporate expenses	$ 12,392	$ 10,965	$ 23,627	$ 21,723