Stock Based Compensation Plan (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, Beginning of Period, in shares	442,385
Granted, in shares	10,000
Stock Options Exercised, in shares	(23,434)	(52,502)
Forfeited, in shares	0
Outstanding, End of Period, in shares	428,951
Exercisable at Period End, in shares	308,470
Vested and Expected to Vest, in shares	428,951
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding at Beginning of Period, in dollars per share	$ 23.03
Granted, in dollars per share	$ 24.28
Excercised, in dollars per share	$ 20.92
Forfeited, in dollars per share	$ 0.00
Outstanding, End of Period, in dollars per share	$ 23.17
Exercisable at Period End, in dollars per share	$ 22.72
Vested and Expected to Vest, in dollars per share	$ 23.17
Fair Value, in dollars per share	$ 5.57
Dividend Yield	4.20%
Expected Volatility	36.57%
Risk Free Interest Rate	1.31%
Expected Lives, in years	6 years 8 months 16 days