Business Combinations (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($) acquisition	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Business Acquisition [Line Items]
Number of Businesses Acquired \| acquisition	2
Payments to Acquire Businesses	$ 26.7
Cash Acquired from Acquisition	3.8
Business Combinations, Guaranteed Deferred Acquisition Obligation	6.5	$ 0.0
Business Combination, contingent earn-out consideration	1.5	$ 1.7
Goodwill, Acquired During Period	35.6
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	10.1
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	(2.6)
Redeemable Noncontrolling Interest	(8.4)		$ 0.0
Payment for Contingent Consideration Liability, Total	41.2
Goodwill, Purchase Accounting Adjustments	0.2
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles	$ (0.2)

Business Combinations, Guaranteed Deferred Acquisition Obligation

No definition available.

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Payment for Contingent Consideration Liability, Total

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No definition available.

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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.

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No definition available.

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- Definition

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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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to intangibles acquired in connection with a business combination for which the initial accounting was incomplete.

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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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- Definition

The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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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 increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

The number of businesses acquired by the entity during the period.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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