PROPERTY PLANT AND EQUIPMENT (PPE BREAKOUT BY TYPE TABLE) (DETAILS) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property Plant and Equipment Line Items
Property, plant and equipment, gross	$ 628,351	$ 575,499	$ 555,054
Less: Accumulated depreciation and amortization	(478,139)	(448,780)
Property, plant and equipment, net	150,212	126,719
Land and buildings [Member]
Property Plant and Equipment Line Items
Property, plant and equipment, gross	38,833	38,833
Computer equipment and software [Member]
Property Plant and Equipment Line Items
Property, plant and equipment, gross	334,127	297,567
Telephone equipment [Member]
Property Plant and Equipment Line Items
Property, plant and equipment, gross	38,925	39,238
Furniture and fixtures [Member]
Property Plant and Equipment Line Items
Property, plant and equipment, gross	57,411	50,638
Leasehold improvements [Member]
Property Plant and Equipment Line Items
Property, plant and equipment, gross	158,844	148,890
Motor vehicles [Member]
Property Plant and Equipment Line Items
Property, plant and equipment, gross	175	188
Construction-in-progress and other [Member]
Property Plant and Equipment Line Items
Property, plant and equipment, gross	$ 36	$ 145