Note 13 - Stockholders' Equity (Details Textual) - USD ($)	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Payments for Repurchase of Common Stock	$ 7,500,000	$ (0)
Stock Repurchased During Period, Shares (in shares)	102,229	0
Stock Repurchased During Period, Average Cost Per Share (in dollars per share)	$ 73.34
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 1,288,167

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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