Earnings Per Share (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Basic Net Income per Common Share Available to Common Stockholders [Abstract]
Net income	$ 8,390,000	$ 6,264,000
Weighted average common shares outstanding	12,671,017	12,475,728
Basic earnings per common share	$ 0.66	$ 0.50
Diluted Net Income per Common Share Available to Common Stockholders [Abstract]
Net income applicable to diluted earnings per share	$ 8,390,000	$ 6,264,000
Weighted average common shares outstanding	12,671,017	12,475,728
Dilutive potential common shares [Abstract]
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	3,980	9,179
Restricted stock awarded	13,250	836
Assumed conversion of preferred stock	0	0
Dilutive potential common shares	17,230	10,015
Diluted weighted average common shares outstanding	12,688,247	12,485,743
Diluted net income per common share available to common stockholders	$ 0.66	$ 0.50