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Stock and Stock-Based Incentive Plans Stock and Stock-Based Incentive Plans (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Aug. 31, 2016	May 31, 2016	Aug. 31, 2017
Stock and Stock-Based Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost	$ 10.9	$ 3.5
Share Repurchase Program
Stock and Stock-Based Incentive Plans
Stock Repurchase Program, Authorized Amount			$ 4,550.0
Available for repurchase, as of end of period	$ 1,890.2		$ 1,251.8

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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

+ 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 (h)(2)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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