GOODWILL AND INTANGIBLE ASSETS (Schedule of Other Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	$ 75,294	$ 75,156
Accumulated amortization	(66,550)	(64,250)
Net carrying value	8,744	10,906
Customer Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	65,423	65,566
Accumulated amortization	(59,472)	(57,682)
Net carrying value	5,951	7,884
Non-compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	5,704	5,701
Accumulated amortization	(5,382)	(5,063)
Net carrying value	322	638
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	1,000	1,000
Accumulated amortization	(1,000)	(1,000)
Net carrying value
Other [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	3,167	2,889
Accumulated amortization	(696)	(505)
Net carrying value	$ 2,471	$ 2,384