Note 8 - Stockholders' Equity (Details Textual) - USD ($)	9 Months Ended
Dec. 26, 2020	Mar. 31, 2020	Dec. 28, 2019
Treasury Stock, Shares, Ending Balance (in shares)	3,097,292
Treasury Stock, Value, Ending Balance	$ 90,473,000	$ 88,319,000	$ 87,194,000
Common Class A [Member]
Treasury Stock, Value, Acquired, Cost Method	2,154,000
Common Class B [Member]
Treasury Stock, Value, Acquired, Cost Method	$ 0

The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

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-Name Accounting Standards Codification
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