Common Stock Plans (Restricted Stock) (Details) (Non-vested restricted stock, Stock Incentive Plan, USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Non-vested restricted stock | Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, vesting period	3 years
Share-based compensation expense	$ 2,000,000	$ 100,000	$ 100,000
Tax benefit related to stock-based compensation	746,000	31,000	47,000
Unrecognized compensation cost	$ 1,200,000
Remaining requisite service period (in years)	2 years 0 months 18 days
Shares
Nonvested, Beginning of Period, Shares	11,115	9,275	24,150
Vested, Shares		(9,275)	(14,875)
Granted, Shares	52,650	11,115
Forfeited, Shares	(1,247)
Nonvested, End of Period, Shares	62,518	11,115	9,275
Weighted Average Price
Nonvested, Beginning of Period, Weighted Average Price (in dollars per share)	$ 45.24	$ 42.99	$ 35.49
Vested, Weighted Average Price (in dollars per share)		$ 42.97	$ 30.81
Granted, Weighted Average Price (in dollars per share)	$ 52.34	$ 45.24
Forfeited, Weighted Average Price (in dollars per share)	$ 48.36
Nonvested, End of Period, Weighted Average Price (in dollars per share)	$ 51.16	$ 45.24	$ 42.99