Acquisition, Intangible Assets and Goodwill (Intangible Assets) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Finite lived intangible assets
Gross Carrying Amount	$ 647,172		$ 647,172		$ 631,288
Accumulated Amortization	(501,796)		(501,796)		(466,116)
Net Carrying Amount	145,376		145,376		165,172
Amortization expense	8,000	$ 10,000	24,000	$ 32,000
Customer relationships
Finite lived intangible assets
Gross Carrying Amount	455,275		455,275		445,039
Accumulated Amortization	(327,947)		(327,947)		(300,906)
Net Carrying Amount	127,328		127,328		144,133
Software & technology
Finite lived intangible assets
Gross Carrying Amount	154,571		154,571		150,037
Accumulated Amortization	(142,604)		(142,604)		(136,508)
Net Carrying Amount	11,967		11,967		13,529
Trademarks & other
Finite lived intangible assets
Gross Carrying Amount	37,326		37,326		36,212
Accumulated Amortization	(31,245)		(31,245)		(28,702)
Net Carrying Amount	$ 6,081		$ 6,081		$ 7,510