Net Income Per Common Share (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Equity Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	249,800	143,925
Average price of anti-dilutive options outstanding	$ 37.04	$ 38.72
Stock Compensation Plan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	93,752
Convertible Debt Securities [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	427,459	427,459