Acquisitions and Divestitures (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Acquisitions:
Purchase price	$ 720.9	$ 125.2	$ 48.8
Net cash paid	714.4	73.2	46.2
Goodwill recorded	495.0us-gaap_GoodwillAcquiredDuringPeriod	37.0us-gaap_GoodwillAcquiredDuringPeriod	20.9us-gaap_GoodwillAcquiredDuringPeriod
Divestitures:
Proceeds	0	35.6	2.1
Gain recognized	0us-gaap_GainLossOnSaleOfBusiness	12.5us-gaap_GainLossOnSaleOfBusiness	1.5us-gaap_GainLossOnSaleOfBusiness
Goodwill charged off	$ 0	$ 4.8	$ 0.1

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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-Publisher FASB

-Name Accounting Standards Codification

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Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

+ References

No definition available.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

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This element represents the cash inflow during the period from the sale of a component of the entity.

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