Note 8 - Stockholders' Equity (Details Textual) - USD ($)	3 Months Ended
Jun. 27, 2020	Mar. 31, 2020	Jun. 29, 2019
Treasury Stock, Value, Acquired, Cost Method	$ 0
Treasury Stock, Shares, Ending Balance (in shares)	3,042,092
Treasury Stock, Value, Ending Balance	$ 88,319,000	$ 88,319,000	$ 78,484,000

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
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-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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