Net Income Per Common Share (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Net Income Per Common Share
Net income	$ 1,225,359	$ 449,104	$ 2,182,167	$ 635,503
Weighted average shares outstanding	10,597,629	10,908,156	10,549,229	10,956,698
Basic net income per common share	$ 0.12	$ 0.04	$ 0.21	$ 0.06
Weighted average shares outstanding	10,597,629	10,908,156	10,549,229	10,956,698
Dilutive potential shares	121,096	98,957	122,393	96,685
Total diluted average shares outstanding	10,718,725	11,007,113	10,671,622	11,053,383
Total diluted net income per share	$ 0.11	$ 0.04	$ 0.20	$ 0.06