Stock And Stock-Based Incentive Plans Stock And Stock-Based Incentive Plans (Unrecognized Compensation Expense) (Details) $ in Millions	12 Months Ended
Feb. 29, 2020 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Costs	$ 58.5
Weighted Average Remaining Recognition Life (Years)	1 year 9 months 18 days
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Costs	$ 40.4
Weighted Average Remaining Recognition Life (Years)	2 years 1 month 6 days
Stock-Settled Market Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Costs	$ 12.7
Weighted Average Remaining Recognition Life (Years)	1 year 1 month 6 days
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Costs	$ 5.0
Weighted Average Remaining Recognition Life (Years)	1 year 2 months 12 days
Deferred Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Costs	$ 0.0
Weighted Average Remaining Recognition Life (Years)	0 years
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Costs	$ 0.4
Weighted Average Remaining Recognition Life (Years)	2 years 9 months 18 days
Total other share-based incentives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Costs	$ 5.4
Weighted Average Remaining Recognition Life (Years)	10 months 24 days

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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