Note 4 - 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, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Net income attributable to First Capital, Inc.	$ 2,109	$ 1,758	$ 5,852	$ 5,123
Weighted average common shares outstanding (in shares)	3,326,513	3,342,015	3,324,550	3,340,066
Net income attributable to First Capital, Inc. per common share, basic (in dollars per share)	$ 0.63	$ 0.53	$ 1.76	$ 1.53
Add: Dilutive effect of restricted stock (in shares)	3,036	2,034	4,561	1,787
Weighted average common shares outstanding, as adjusted (in shares)	3,329,549	3,344,049	3,329,111	3,341,853
Net income attributable to First Capital, Inc. per common share, diluted (in dollars per share)	$ 0.63	$ 0.53	$ 1.76	$ 1.53