Note 2 - Marketable Securities - Summary of Realized Gains/Losses on Available-for-Sale Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Feb. 28, 2021	Mar. 01, 2020	Mar. 03, 2019
Gross realized gains on sale	$ 155	$ 90
Gross realized losses on sale	$ 145	$ 75	$ 1,498

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

No definition available.

Name:	us-gaap_AvailableForSaleSecuritiesGrossRealizedGains
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration