Earnings Per Common Share and Share Awards Summary Of Share-Based Award Transactions (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number Of Shares, Options exercised	(1,000)	(2,650)	(6,380)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted Average Exercise Price, Options exercised	$ 27.21	$ 28.63	$ 25.17
StockOptionsAndStockAppreciationRightsSARS
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number Of Shares, Outstanding Beginning Balance	19,000	98,150	101,600
Number Of Shares, Options/SARs cancelled/forfeited/expired	0	0	(70)
Number Of Shares, Outstanding Ending Balance	21,000	19,000	98,150	101,600
Number Of Shares, Exercisable as of December 31, 2014	19,875
Number Of Shares, Unvested as of December 31, 2014	1,125
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted Average Exercise Price, Outstanding Beginning Balance	$ 45.74	$ 30.74	$ 29.81
Weighted Average Exercise Price, Options/SARs cancelled/forfeited/expired	$ 0.00	$ 0.00	$ 31.00
Weighted Average Exercise Price, Outstanding Ending Balance	$ 51.30	$ 45.74	$ 30.74	$ 29.81
Weighted Average Exercise Price, Exercisable as of December 31, 2014	$ 50.32
Weighted Average Exercise Price, Unvested as of December 31, 2014	$ 68.70
Average Remaining Contractual Term, Outstanding Beginning Balance	3 years 7 months 20 days	3 years 5 months 4 days	3 years 2 months 1 day	3 years 10 months 27 days
Average Remaining Contractual Term, Outstanding Ending Balance	3 years 7 months 20 days	3 years 5 months 4 days	3 years 2 months 1 day	3 years 10 months 27 days
Average Remaining Contractual Term, Exercisable as of December 31, 2014	3 years 5 months 26 days
Average Remaining Contractual Term, Unvested as of December 31, 2014	6 years 4 months 20 days
Aggregate Intrinsic Value, Outstanding Beginning Balance	$ 669,610	$ 2,871,710	$ 697,780
Aggregate Intrinsic Value, Outstanding Ending Balance	453,510	669,610	2,871,710	697,780
Aggregate Intrinsic Value, Exercisable as of December 31, 2014	448,785
Aggregate Intrinsic Value, Unvested as of December 31, 2014	$ 4,725
SARs
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number Of Shares, SARs granted	4,500	3,000	3,000
Number Of Shares, Options exercised	(1,500)	(79,500)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted Average Exercise Price, SARs granted	$ 68.70	$ 71.59	$ 50.50
Weighted Average Exercise Price, Options exercised	$ 49.04	$ 28.77