Note 5 - Supplemental Disclosure for Earnings Per Share - Supplemental Disclosure for Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Net income attributable to First Capital, Inc.	$ 2,147	$ 2,133
Weighted average common shares outstanding (in shares)	3,329,844	3,326,464
Net income attributable to First Capital, Inc. per common share, basic (in dollars per share)	$ 0.64	$ 0.64
Weighted average common shares outstanding (in shares)	3,329,844	3,326,464
Add: Dilutive effect of restricted stock (in shares)	10,100	5,671
Weighted average common shares outstanding, as adjusted (in shares)	3,339,944	3,332,135
Net income attributable to First Capital, Inc. per common share, diluted (in dollars per share)	$ 0.64	$ 0.64