Intangible Assets Goodwill (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Goodwill [Line Items]
Goodwill	$ 340,743,000us-gaap_Goodwill	$ 12,274,000us-gaap_Goodwill	$ 2,209,000us-gaap_Goodwill
Goodwill, Acquired During Period	332,124,000us-gaap_GoodwillAcquiredDuringPeriod	10,090,000us-gaap_GoodwillAcquiredDuringPeriod
Goodwill, Translation Adjustments	(3,655,000)us-gaap_GoodwillTranslationAdjustments	(25,000)us-gaap_GoodwillTranslationAdjustments
Goodwill, Period Increase (Decrease)	328,500,000us-gaap_GoodwillPeriodIncreaseDecrease
CMH
Goodwill [Line Items]
Goodwill	47,483,000	12,274,000	2,209,000
Goodwill, Acquired During Period	35,329,000	10,090,000
Goodwill, Translation Adjustments	(120,000)	(25,000)
EM
Goodwill [Line Items]
Goodwill	293,260,000	0	0
Goodwill, Acquired During Period	296,795,000	0
Goodwill, Translation Adjustments	$ (3,535,000)	$ 0

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

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 45

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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+ References

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