Fair Value Measurements Unobservable Input (level 3) Reconciliation (Details) $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Net change in contingent acquisition obligations	$ 61.5
Contingent acquisition obligations, additions	105.8
Contingent acquisition obligations, payments	$ (65.1)

Amount of increase in the value of a contingent consideration liability, including, but not limited to, acquisitions and exercised put options.

No definition available.

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- Definition

Amount of decrease in the value of a contingent consideration liability due to payments to acquirees.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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