Financial Instruments (Details) - USD ($) $ in Thousands	Feb. 27, 2021	Feb. 29, 2020
Amortized cost, gross unrealized gains and losses, and estimated fair values of investments available for sale
Amortized Cost	$ 12,517	$ 11,692
Gross Unrealized Gains	(386)	(275)
Gross Unrealized Losses	(10)	0
Estimated Fair Value	12,893	$ 11,967
Municipal bonds
Amortized cost, gross unrealized gains and losses, and estimated fair values of investments available for sale
Amortized Cost	12,517
Estimated Fair Value	$ 12,893

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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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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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

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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).

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