Financial Instruments (Details) - USD ($) $ in Thousands	Feb. 29, 2020	Mar. 02, 2019
Amortized cost, gross unrealized gains and losses, and estimated fair values of investments available for sale
Amortized Cost	$ 11,692	$ 12,481
Gross Unrealized Gains	(275)	(59)
Gross Unrealized Losses	0	(108)
Estimated Fair Value	11,967	$ 12,432
Municipal bonds
Amortized cost, gross unrealized gains and losses, and estimated fair values of investments available for sale
Amortized Cost	11,692
Estimated Fair Value	$ 11,967

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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- Definition

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
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-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

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-Publisher FASB
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