Acquisitions, Divestiture, Intangible Assets and Goodwill (Acquisitions) (Details) - USD ($) $ in Thousands	1 Months Ended				3 Months Ended	12 Months Ended
	Jul. 31, 2016	Jan. 31, 2016	Jun. 30, 2015	May 31, 2015	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Purchase price						$ 37,842	$ 393,695	$ 0
Proceeds from sale of businesses, net of cash transferred				$ 292,000		0	289,211	102,392
Gain on sale of businesses				$ 111,000		$ (5,786)	105,826	$ 28,151
Maponics
Business Acquisition [Line Items]
Purchase price	$ 24,000
Enroute
Business Acquisition [Line Items]
Purchase price in cash		$ 14,000
Borderfree
Business Acquisition [Line Items]
Purchase price			$ 381,000
Cash acquired			$ 92,000
Accounts payable, accrued expenses and goodwill acquired					$ 2,000
Pro forma revenues							$ 47,000