Stock-Based Compensation (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Summary the stock option transactions
Number of Options, Forfeited/canceled/expired		(59,000)
Stock Option Plan [Member]
Summary the stock option transactions
Number of Options, Outstanding	29,035	213,170	233,787
Number of Options, Granted	0	0	0
Number of Options, Exercised	0	(125,354)	(7,294)
Number of Options, Forfeited/canceled/expired	0	(58,781)	(13,323)
Number of Options, Outstanding	29,035	29,035	213,170	233,787
Number of Options, Vested and Exercisable	29,035
Weighted Average Exercise Price, Outstanding	$ 28.47	$ 31.79	$ 33.38
Weighted Average Exercise Price, Granted	0	0	0
Weighted Average Exercise Price, Exercised	0	27.09	34.80
Weighted Average Exercise Price, Forfeited/canceled/expired	0	43.47	57.93
Weighted Average Exercise Price, Outstanding	28.47	$ 28.47	$ 31.79	$ 33.38
Weighted Average Exercise Price, Vested and Exercisable	$ 28.47
Weighted Average Remaining Contractual Term (Years), Outstanding	4 months 24 days	1 year 4 months 24 days	1 year 2 months 12 days	2 years 1 month 6 days
Weighted Average Remaining Contractual Term (Years) Vested and Exercisable	4 months 24 days
Aggregate Intrinsic Value, Outstanding	$ 633,834	$ 289,769	$ 2,519,147	$ 4,058,035
Aggregate Intrinsic Value, Vested and Exercisable	$ 633,834