Share-Based Compensation Plans (Narrative) (Details) - USD ($) $ / shares in Millions, $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 56.0	$ 25.8
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, grants in period (in shares)	468,381
Options, grants date fair value	$ 9.0
Share based compensation expense, employees expensed in entirety	$ 5.5	5.5
Share-based compensation expense	$ 6.3	6.4
Restricted Stock Unit Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options, grants in period (in shares)	839,354
Other than options, grants in period fair value	$ 73.9
Share based compensation expense, employees expensed in entirety	$ 21.6
Share-based compensation expense	41.2	15.3
Share-based compensation expense for fully vested equity options	$ 2.5	$ 2.0
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options, grants in period (in shares)	206,091
Other than options, grants in period fair value	$ 18.1
Share-based compensation expense	$ 3.3

Allocated Share-based Compensation Expense, Employees Expensed In Entirety

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- Definition

Allocated Stock Compensation Expense For Fully Vested Equity Options

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

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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- Definition

Gross 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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