GOODWILL AND INTANGIBLE ASSETS - Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 33,350	$ 33,350
Accumulated Amortization	(28,222)	(23,081)
Net Carrying Amount	5,128	10,269
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	25,650	25,650
Accumulated Amortization	(20,789)	(16,615)
Net Carrying Amount	4,861	9,035
Trademarks
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	6,200	6,200
Accumulated Amortization	(6,200)	(5,333)
Net Carrying Amount	0	867
Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,500	1,500
Accumulated Amortization	(1,233)	(1,133)
Net Carrying Amount	$ 267	$ 367