Stock-Based Compensation (Schedule Of Activity For Non-Vested Restricted Sock) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Stock-Based Compensation [Abstract]
Non-vested at beginning of period, Shares	6,730	3,328	0
Granted, Shares	1,695	3,402	3,328
Forfeited, Shares	(32)	0	0
Non-vested at end of period, Shares	8,393	6,730	3,328
Non-vested at beginning of period, Weighted Average Fair Value at Grant Date	$ 101.26	$ 109.38
Granted, Weighted Average Fair Value at Grant Date	$ 76.43	$ 93.32	$ 109.38
Forfeited, Weighted Average Fair Value at Grant Date	$ 93.60
Non-vested at end of period, Weighted Average Fair Value at Grant Date	$ 96.28	$ 101.26	$ 109.38