Note 11 - Common Stock and Class B Common Stock (Details Textual) - $ / shares	Sep. 26, 2021	Mar. 30, 2018	Mar. 30, 2017
Class of Warrant or Right, Outstanding (in shares)	600,000
Warrant Agreement [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			600,000
Class of Warrant or Right, Percentage of Common Stock Outstanding			10.10%
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 41.90
Class of Warrant or Right, Outstanding (in shares)	71,000	16,930,000