Note 8 - Supplemental Disclosure for Earnings Per Share - Supplemental Disclosure for Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Net income attributable to First Capital, Inc.	$ 2,952	$ 3,816
Weighted average common shares outstanding (in shares)	3,345,060	3,353,623
Net income attributable to First Capital, Inc. per common share, basic (in dollars per share)	$ 0.88	$ 1.14
Net income attributable to First Capital, Inc.	$ 2,952	$ 3,816
Weighted average common shares outstanding (in shares)	3,345,060	3,353,623
Add: Dilutive effect of restricted stock (in shares)	0	0
Weighted average common shares outstanding, as adjusted (in shares)	3,345,060	3,353,623
Net income attributable to First Capital, Inc. per common share, diluted (in dollars per share)	$ 0.88	$ 1.14