Stock And Stock-Based Incentive Plans Stock and Stock-Based Incentive Plans (Settled) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
May 31, 2017	May 31, 2016
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted, Number of Shares	1,930,362	2,154,718
Weighted average grant date fair value per share	$ 16.11	$ 14.19
Cash received from options exercised	$ 6.6	$ 4.1
Intrinsic value of options exercised	3.2	4.9
Realized tax benefits	$ 1.3	$ 1.9
Cash-settled restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock units granted, Number of Units	627,127	631,907
Weighted average grant date fair value per share	$ 58.38	$ 51.63
Payments (before payroll tax withholdings) upon vesting	$ 25.9	$ 22.9
Realized tax benefits	$ 10.4	$ 9.0
Stock-settled market stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock units granted, Number of Units	158,637	168,681
Weighted average grant date fair value per share	$ 73.58	$ 63.97
Realized tax benefits	$ 7.0	$ 5.2
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock units granted, Number of Units	73,648	83,032
Weighted average grant date fair value per share	$ 58.38	$ 51.63
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock units granted, Number of Units	0	19,998
Weighted average grant date fair value per share	$ 0.00	$ 51.63

Share-based Compensation Arrangement by Share-based Payment Award, Payments Upon Vesting

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- Definition

Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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- Definition

The cash inflow associated with the amount received from holders exercising their stock options. 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 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (j)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: 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 3: 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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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).

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

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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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