FIXED ASSETS (Components of Fixed Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 92,827	$ 88,781
Accumulated depreciation	(60,184)	(57,932)
Property, plant and equipment, net, total	32,643	30,849
Furniture and fixtures [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	5,745	5,701
Computer hardware and software [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	69,973	68,387
Equipment [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	5,173	3,326
Leasehold improvements [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 11,936	$ 11,367