Note 5 - 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, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Net income attributable to First Capital, Inc.	$ 2,915	$ 2,524	$ 7,922	$ 6,757
Weighted average common shares outstanding (in shares)	3,335,816	3,329,833	3,331,854	3,327,710
Net income attributable to First Capital, Inc. per common share, basic (in dollars per share)	$ 0.87	$ 0.76	$ 2.38	$ 2.03
Weighted average common shares outstanding (in shares)	3,335,816	3,329,833	3,331,854	3,327,710
Add: Dilutive effect of restricted stock (in shares)	8,506	4,971	11,322	5,820
Weighted average common shares outstanding, as adjusted (in shares)	3,344,322	3,334,804	3,343,176	3,333,530
Net income attributable to First Capital, Inc. per common share, diluted (in dollars per share)	$ 0.87	$ 0.76	$ 2.37	$ 2.03