Intangible Asset and Goodwill (Details 2) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Goodwill
Gross Carrying Amount	$ 138,669us-gaap_GoodwillGross
Accumulated Impairment Losses	(21,770)
Net Carrying Amount	116,899us-gaap_Goodwill	116,899us-gaap_Goodwill
MID Segment
Goodwill
Gross Carrying Amount	19,905
Accumulated Impairment Losses	0
Net Carrying Amount	19,905	19,905
CRD Segment
Goodwill
Gross Carrying Amount	96,994
Accumulated Impairment Losses	0
Net Carrying Amount	96,994	96,994
Other
Goodwill
Gross Carrying Amount	21,770
Accumulated Impairment Losses	(21,770)
Net Carrying Amount	$ 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

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 before 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.

+ 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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