Financial Instruments (Details 2) - USD ($) $ in Thousands	Feb. 27, 2021	Feb. 29, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost, Due after 15 years	$ 800
Amortized Cost	12,517	$ 11,692
Estimated Market Value, After 15 years	829
Estimated Fair Value	12,893	$ 11,967
Municipal bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost, Due within one year	873
Amortized Cost, Due after one year through five years	8,610
Amortized Cost, Due after five years through 10 years	2,234
Amortized Cost	12,517
Estimated Market Value, Due within one year	881
Estimated Market Value, Due after one year through five years	8,906
Estimated Market Value, Due after five years through 10 years	2,277
Estimated Fair Value	$ 12,893

Amortized cost 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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