Income Taxes (Details 2)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Statutory federal income tax rate	35.00%	35.00%	35.00%
Increase (decrease) due to
State income taxes	3.41%	5.57%	5.26%
Deferred tax adjustment related to Tax Act	7.85%
Tax exempt interest and dividend income	(0.61%)	(0.98%)	(1.25%)
Stock-based compensation expense	0.01%	0.01%	0.02%
Other	0.38%	(1.01%)	(1.28%)
Effective tax rates	46.04%	38.59%	37.75%