Acquisitions and Divestitures (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Acquisitions:
Purchase price	$ 46.2	$ 720.9	$ 125.2
Net cash paid	46.2	714.4	73.2
Goodwill recorded	0.0	495.0	37.0
Divestitures:
Proceeds	51.3	0.0	35.6
Gain recognized	8.3	0.0	12.5
Goodwill charged off	$ 17.3	$ 0.0	$ 4.8

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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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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.

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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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