Note 8 - Supplemental Disclosure for Earnings Per Share - Supplemental Disclosure for Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Net income attributable to First Capital, Inc.	$ 3,138	$ 3,125	$ 9,680	$ 8,362
Weighted average common shares outstanding (in shares)	3,345,869	3,358,800	3,347,823	3,353,459
Net income attributable to First Capital, Inc. per common share, basic (in dollars per share)	$ 0.94	$ 0.93	$ 2.89	$ 2.49
Net income attributable to First Capital, Inc.	$ 3,138	$ 3,125	$ 9,680	$ 8,362
Weighted average common shares outstanding (in shares)	3,345,869	3,358,800	3,347,823	3,353,459
Add: Dilutive effect of restricted stock (in shares)	0	0	0	0
Weighted average common shares outstanding, as adjusted (in shares)	3,345,869	3,358,800	3,347,823	3,353,459
Net income attributable to First Capital, Inc. per common share, diluted (in dollars per share)	$ 0.94	$ 0.93	$ 2.89	$ 2.49