Stock Incentive Plan Summary of Stock Option Activity (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, beginning of year	40,500	45,500	52,000
Granted	0	0	0
Exercised	(27,500)	(2,500)	0
Forfeited or expired	(2,500)	(2,500)	(6,500)
Outstanding, end of year	10,500	40,500	45,500
Options, Exercisable, Number	10,500	40,500	45,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding Options, Weighted Average Exercise Price, Beginning of Year	$ 24.65	$ 24.67	$ 24.64
Options, Grants in Period, Weighted Average Exercise Price	0	0.00	0.00
Options, Exercises in Period, Weighted Average Exercise Price	25.42	24.86	0.00
Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	23.00	24.86	24.43
Outstanding Options, Weighted Average Exercise Price, End of Year	23.00	24.65	24.67
Options, Exercisable, Weighted Average Exercise Price	$ 23.00	$ 24.65	$ 24.67
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options, Outstanding, Weighted Average Remaining Contractual Term	350 days	1 year 153 days	2 years 153 days
Options, Exercisable, Weighted Average Remaining Contractual Term	350 days	1 year 153 days	2 years 153 days
Options, Outstanding, Intrinsic Value	$ 163,170	$ 378,850	$ 63,000
Options, Exercisable, Intrinsic Value	163,170	378,850	$ 63,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 259,000	$ 14,000
Antidilutive Outstanding option shares			24,500