Acquisitions (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Business Acquisition [Line Items]
Total cash consideration paid for acquisitions, net of cash acquired	$ 21.2	$ 41.2
Payments of contingent consideration for acquisitions	12.9	$ 2.9
7S Group GmbH
Business Acquisition [Line Items]
Payments of contingent consideration for acquisitions	$ 10.3

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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