Goodwill And Intangible Assets (Changes In Carrying Amounts Of Goodwill And Other Intangible Assets) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($)
Goodwill [Line Items]
Balance as of January 1, 2017	$ 1,122,810
Goodwill, Acquired During Period	24,378
Goodwill, Transfers	(17,815)
Goodwill, Purchase Accounting Adjustments	567
Foreign Exchange Translation	9,486
Balance as of June 30, 2017	1,139,426
Business Cloud Services Segment [Member]
Goodwill [Line Items]
Balance as of January 1, 2017	559,152
Goodwill, Acquired During Period	24,378
Goodwill, Transfers	0
Goodwill, Purchase Accounting Adjustments	(766)
Foreign Exchange Translation	9,365
Balance as of June 30, 2017	592,129
Digital Media Segment [Member]
Goodwill [Line Items]
Balance as of January 1, 2017	563,658
Goodwill, Acquired During Period	0
Goodwill, Transfers	(17,815)
Goodwill, Purchase Accounting Adjustments	1,333
Foreign Exchange Translation	121
Balance as of June 30, 2017	$ 547,297