Cancellation Reserves (Schedule Of Cancellation Reserves Accrual) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Aug. 31, 2017	Aug. 31, 2016	Aug. 31, 2017	Aug. 31, 2016
Cancellation Reserves [Abstract]
Balance as of beginning of period	$ 109.0	$ 112.5	$ 108.2	$ 110.2
Cancellations	(16.6)	(16.4)	(32.9)	(32.8)
Provision for future cancellations	17.4	17.2	34.5	35.9
Balance as of end of period	$ 109.8	$ 113.3	$ 109.8	$ 113.3

Contract Cancellation Reserves [Abstract]

No definition available.

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

+ Details

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- Definition

Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses.

+ References

+ Details

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- Definition

Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

+ References

+ Details

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