Note 3 - Investment Securities (Details) - USD ($) $ in Millions	Feb. 27, 2016	Feb. 28, 2015
Available-for-sale securities:
Long term	$ 19.8	$ 47.9
Trading securities:
Deferred Compensation Plan Assets	51.5	49.2
Held-to-maturity securities:
Short term	86.2	110.0
Total investment securities	$ 157.5	$ 207.1

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Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Equity securities categorized neither as held-to-maturity nor trading which are intended be sold more than one year from the balance sheet date or operating cycle, if longer.

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Carrying amount as of the balance sheet date of assets held under deferred compensation agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Sum of the carrying amounts as of the balance sheet date of all investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 944
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