GOODWILL AND OTHER INTANGIBLE ASSETS - Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Other Intangible Assets
Cost	$ 560,043		$ 551,853
Accumulated Amortization	250,593		233,856
Net Book Value	309,450		317,997
Amortization of expense	17,300	$ 23,200
Contract rights under placement fee agreements
Other Intangible Assets
Cost	20,334		17,742
Accumulated Amortization	7,831		6,281
Net Book Value	$ 12,503		11,461
Contract rights under placement fee agreements | Minimum
Other Intangible Assets
Useful Life (years)	1 year
Contract rights under placement fee agreements | Maximum
Other Intangible Assets
Useful Life (years)	7 years
Customer contracts
Other Intangible Assets
Cost	$ 50,975		50,975
Accumulated Amortization	41,427		40,419
Net Book Value	$ 9,548		10,556
Customer contracts | Minimum
Other Intangible Assets
Useful Life (years)	7 years
Customer contracts | Maximum
Other Intangible Assets
Useful Life (years)	14 years
Customer relationships
Other Intangible Assets
Cost	$ 231,100		231,100
Accumulated Amortization	47,929		42,688
Net Book Value	$ 183,171		188,412
Customer relationships | Minimum
Other Intangible Assets
Useful Life (years)	8 years
Customer relationships | Maximum
Other Intangible Assets
Useful Life (years)	12 years
Developed technology and software
Other Intangible Assets
Cost	$ 228,392		224,265
Accumulated Amortization	134,597		126,721
Net Book Value	$ 93,795		97,544
Developed technology and software | Minimum
Other Intangible Assets
Useful Life (years)	1 year
Developed technology and software | Maximum
Other Intangible Assets
Useful Life (years)	6 years
Patents, trademarks and other
Other Intangible Assets
Cost	$ 29,242		27,771
Accumulated Amortization	18,809		17,747
Net Book Value	$ 10,433		$ 10,024
Patents, trademarks and other | Minimum
Other Intangible Assets
Useful Life (years)	1 year
Patents, trademarks and other | Maximum
Other Intangible Assets
Useful Life (years)	17 years