Intangible Asset and Goodwill (Details) $ in Thousands	9 Months Ended
Sep. 30, 2017 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 204,794
Additions to Goodwill	803
Impairment of Goodwill	0
Goodwill, Translation Adjustments	3,721
Ending Balance	209,318
MID Segment
Goodwill [Roll Forward]
Beginning Balance	66,643
Additions to Goodwill	0
Impairment of Goodwill	0
Goodwill, Translation Adjustments	0
Ending Balance	66,643
RSD Segment
Goodwill [Roll Forward]
Beginning Balance	138,151
Impairment of Goodwill	0
Goodwill, Translation Adjustments	3,721
Ending Balance	142,675
Other
Goodwill [Roll Forward]
Ending Balance	0
Goodwill [Member] \| RSD Segment
Goodwill [Roll Forward]
Additions to Goodwill	$ 803

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
-Subparagraph (a)
-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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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+ References

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down 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 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 350
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-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
-Paragraph 28
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-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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