Consolidated Balance Sheets (Parenthetical) - USD ($)	Mar. 31, 2017	Dec. 31, 2016
Statement Of Financial Position [Abstract]
Securities held to maturity, fair value	$ 49,769,285	$ 49,731,169
Preferred stock, par value	$ 1	$ 1
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	878,049	878,049
Preferred stock, shares outstanding	878,049	878,049
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	20,000,000	20,000,000
Common stock, shares issued	11,218,328	11,204,515
Common stock, shares outstanding	11,218,328	11,204,515