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Description of Business (Details)	12 Months Ended
	Dec. 31, 2018 Employee Country Location
Product Information [Line Items]
Number of employees | Employee	13,670
Number of locations in which company operates | Location	89
Number of countries in which company operates | Country	37
Geographic Concentration Risk | United States | Net Revenue
Product Information [Line Items]
Percentage of company revenue	34.50%
Geographic Concentration Risk | Europe | Net Revenue
Product Information [Line Items]
Percentage of company revenue	55.70%
Geographic Concentration Risk | Rest of World | Net Revenue
Product Information [Line Items]
Percentage of company revenue	9.80%

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 825
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-Section 50
-Paragraph 20
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