Note 4 - Investment Securities - Summary of Investment Securities (Details) - USD ($) $ in Millions	Feb. 25, 2017	Feb. 27, 2016
Available-for-sale securities:
Long term	$ 19.3	$ 19.8
Trading securities:
Long term	70.3	51.5
Held-to-maturity securities:
Held-to-maturity Securities, Current		86.2
Total investment securities	$ 89.6	$ 157.5

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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.

+ References

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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