Schedule of Share Based Compensation Stock Options (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Intrinsic Value of Stock Options Exercised	$ 7.5	$ 31.1	$ 34.7	$ 55.3
Stock Compensation Expense Related to Stock Option Awards	$ 9.0	$ 5.7	$ 10.7	$ 11.2
Issued Stock Options	1.8	1.3	1.8	2.0
Weighted Average Fair Value of Stock Options issued (per share)	$ 9.70	$ 8.06	$ 9.67	$ 7.58
Fair Value of Stock Options Issued	$ 17.1	$ 10.2	$ 17.5	$ 15.2

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

Net number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

The fair value of stock issued in noncash financing activities.

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The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

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