Goodwill And Intangible Assets (Changes In Carrying Amounts Of Goodwill And Other Intangible Assets) (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Goodwill [Line Items]
Balance at beginning period	$ 457,422,000us-gaap_Goodwill
Goodwill, Acquired During Period	184,837,000us-gaap_GoodwillAcquiredDuringPeriod	54,472,000us-gaap_GoodwillAcquiredDuringPeriod
Goodwill, Purchase Accounting Adjustments	(1,035,000.000000000)
Foreign Exchange Translation	(5,549,000)us-gaap_GoodwillTranslationAdjustments
Balance at ending period	635,675,000us-gaap_Goodwill	457,422,000us-gaap_Goodwill
Business Cloud Services Segment [Member]
Goodwill [Line Items]
Balance at beginning period	316,682,000	294,943,000
Goodwill, Acquired During Period	79,536,000	21,551,000
Goodwill, Purchase Accounting Adjustments	(706,000.000000000)		(259,000)
Foreign Exchange Translation	(5,449,000)	447,000
Balance at ending period	390,063,000	316,682,000	294,943,000
Digital Media Segment [Member]
Goodwill [Line Items]
Balance at beginning period	140,740,000	112,882,000
Goodwill, Acquired During Period	105,301,000	32,921,000
Goodwill, Purchase Accounting Adjustments	(329,000.000000000)		(5,065,000)
Foreign Exchange Translation	(100,000)	2,000
Balance at ending period	$ 245,612,000	$ 140,740,000	$ 112,882,000

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e961-128460

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Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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