Note 5 - Supplemental Disclosure for Earnings Per Share - Supplemental Disclosure for Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net income attributable to First Capital, Inc.	$ 2,100	$ 2,190	$ 4,233	$ 3,743
Weighted average common shares outstanding (in shares)	3,326,797	3,323,552	3,326,632	3,323,552
Basic (in dollars per share)	$ 0.63	$ 0.66	$ 1.27	$ 1.13
Weighted average common shares outstanding (in shares)	3,326,797	3,323,552	3,326,632	3,323,552
Add: Dilutive effect of restricted stock (in shares)	7,041	5,488	6,401	5,286
Weighted average common shares outstanding, as adjusted (in shares)	3,333,838	3,329,040	3,333,033	3,328,838
Diluted (in dollars per share)	$ 0.63	$ 0.66	$ 1.27	$ 1.12