Income Taxes - Schedule of Income Taxes (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Taxes at statutory income tax rate									$ 1,845,313	$ 1,763,394	$ 1,428,272
Reductions in taxes resulting from exempt income									(524,347)	(547,556)	(540,861)
Other timing differences									298,934	(63,362)	(60,247)
Total income taxes	$ 735,000	$ 261,000	$ 316,000	$ 308,000	$ 280,000	$ 299,000	$ 259,000	$ 314,000	$ 1,619,900	$ 1,152,476	$ 827,164
Taxes at statutory income tax rate, percentage									34.00%	34.00%	34.00%
Reductions in taxes resulting from exempt income, percentage									(9.70%)	(10.60%)	(12.90%)
Other timing differences, percentage									5.50%	(1.20%)	(1.40%)
Total income taxes, percentage									29.80%	22.20%	19.70%