Stock and Stock-Based Incentive Plans Stock and Stock-Based Incentive Plans (Schedule of Common Stock Repurchases) (Details) - Share Repurchase Program - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Aug. 31, 2020	Aug. 31, 2019	Aug. 31, 2020	Aug. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares repurchased	0	1,525,500	515,500	4,478,600
Average Cost Per Share	$ 0	$ 84.13	$ 78.96	$ 74.38
Available for repurchase, as of end of period	$ 1,511.6	$ 1,780.8	$ 1,511.6	$ 1,780.8

Number of shares that have been repurchased during the period and are being held in treasury.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration