PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, plant and equipment, net [Abstract]
Property, plant and equipment, Gross	$ 148.2	$ 173.0
Less accumulated depreciation and amortization	109.9	131.8
Property, plant and equipment, net	38.3	41.2
Included in property, plant and equipment are assets under capital leases [Abstract]
Office, computer and other equipment	17.5	17.7
Less: Accumulated amortization	16.3	14.6
Property, plant and equipment, assets under capital leases, net	1.2	3.1
Depreciation	11.1	15.4	$ 17.4
NATG [Member]
Included in property, plant and equipment are assets under capital leases [Abstract]
Depreciation	3.1	8.5	$ 11.9
Land and Buildings [Member]
Property, plant and equipment, net [Abstract]
Property, plant and equipment, Gross	17.7	18.6
Furniture and Fixtures, Office, Computer and Other Equipment and Software [Member]
Property, plant and equipment, net [Abstract]
Property, plant and equipment, Gross	108.7	127.6
Leasehold Improvements [Member]
Property, plant and equipment, net [Abstract]
Property, plant and equipment, Gross	$ 21.8	$ 26.8