Note 3 - Marketable Securities - Summary of Unrealized Gains/Losses on Available-for-Sale Securities (Details) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2014	Mar. 02, 2014
U.S. Treasury and other government securities	$ 134,697	$ 136,994
U.S. Treasury and other government securities	371	213
U.S. Treasury and other government securities	17	1
Domestic Corporate Debt Securities [Member]
U.S. Treasury and other government securities	20,311	24,401
U.S. Treasury and other government securities	8	13
U.S. Treasury and other government securities	10	1
US Treasury and Government [Member]
U.S. Treasury and other government securities	114,386	112,593
U.S. Treasury and other government securities	363	200
U.S. Treasury and other government securities	$ 7

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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