Note 7 - Stockholders' Equity (Details Textual) - USD ($)	9 Months Ended
Dec. 28, 2019	Mar. 31, 2019	Dec. 29, 2018
Treasury Stock, Shares, Ending Balance	3,008,762
Treasury Stock, Value, Ending Balance	$ 87,194,000	$ 75,740,000	$ 74,896,000
Common Class A [Member]
Treasury Stock, Value, Acquired, Cost Method	7,571,000
Common Class B [Member]
Treasury Stock, Value, Acquired, Cost Method	$ 3,883,000

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 30
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