Reportable Business Segments, Reconciliation of Segment Operating Income (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Reconciliation of segment operating income to consolidated income before income taxes
Segment operating income	$ 314.1	$ 239.4
Interest expense	(19.3)	(18.1)
Other income, net	3.6	1.0
Stock-based compensation expense	(12.1)	(11.6)
Acquisition-related expenses		(30.3)
Other operating expenses	(11.4)	(11.0)
Income before income taxes	298.4	222.3
Operating Segment
Reconciliation of segment operating income to consolidated income before income taxes
Segment operating income	$ 337.6	$ 292.3

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Amount of the cost of borrowed funds accounted for as interest expense.

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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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