Note 7 - Net Income Per Share (Details) - shares	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Weighted average number of common shares outstanding - basic (in shares)	2,742,511	2,692,033
Dilutive effect of outstanding stock options and non-vested restricted stock units (in shares)	165,946	211,602
Diluted weighted average shares outstanding (in shares)	2,908,457	2,903,635

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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