Share-based Compensation (Summary of Stock Award Information) (Schedule) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Assumptions used to estimate fair value of options, SARs and PSARs granted:
Cash received from exercise of options	$ 17.4	$ 40.5	$ 54.8
Income tax benefit related to share-based compensation expense	$ 55.2	$ 67.4	$ 54.6
Options, SARs and PSARs \| Minimum [Member]
Assumptions used to estimate fair value of options, SARs and PSARs granted:
Risk-free interest rate	0.88%	0.96%	0.81%
Expected life	3 years 2 months 12 days	3 years	3 years 1 month 6 days
Expected volatility	27.40%	23.10%	25.10%
Expected dividend yield	0.00%	0.00%	0.00%
Options, SARs and PSARs \| Maximum [Member]
Assumptions used to estimate fair value of options, SARs and PSARs granted:
Risk-free interest rate	1.49%	1.89%	1.77%
Expected life	5 years 6 months	5 years 6 months	5 years 1 month 5 days
Expected volatility	42.90%	30.10%	28.70%
Expected dividend yield	0.00%	0.00%	0.00%
Options
Assumptions used to estimate fair value of options, SARs and PSARs granted:
Weighted average grant-date fair value per share of awards granted, options (in dollars per share)	$ 10.40	$ 14.73	$ 11.40
Total intrinsic value of awards exercised	$ 16.9	$ 106.8	$ 126.6
SARs
Assumptions used to estimate fair value of options, SARs and PSARs granted:
Weighted average grant-date fair value per share of awards granted, other than options (in dollars per share)	$ 8.60	$ 10.76	$ 8.93
Total intrinsic value of awards exercised	$ 42.2	$ 51.7	$ 48.7
PSARs
Assumptions used to estimate fair value of options, SARs and PSARs granted:
Weighted average grant-date fair value per share of awards granted, other than options (in dollars per share)	$ 0	$ 0	$ 8.15
Total intrinsic value of awards exercised	$ 0.7	$ 0.2	$ 0.4
RSUs
Assumptions used to estimate fair value of options, SARs and PSARs granted:
Weighted average grant-date fair value per share of awards granted, other than options (in dollars per share)	$ 36.67	$ 51.85	$ 40.68
PSUs
Assumptions used to estimate fair value of options, SARs and PSARs granted:
Weighted average grant-date fair value per share of awards granted, other than options (in dollars per share)	33.97	51.57	40.42
PGUs
Assumptions used to estimate fair value of options, SARs and PSARs granted:
Weighted average grant-date fair value per share of awards granted, other than options (in dollars per share)	$ 0	$ 0	$ 44.04

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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The total cash inflow associated with the amount received from holders to acquire the entity's shares under incentive and share awards, including stock option exercises. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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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

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

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.

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- Definition

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

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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