Equity-Based Compensation Plans (Summary Of Outstanding Performance Share Awards / Restricted Stock Units) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Performance shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested shares outstanding at January 1, Shares	160,214	154,594	184,601
Granted (in shares)	83,111	85,028	77,767
Vested (in shares)	(71,861)	(76,812)	(103,960)
Forfeited (in shares)	(15,650)	(2,596)	(3,814)
Unvested shares outstanding at December 31, Shares	155,814	160,214	154,594
Unvested shares outstanding at January 1, Weighted Avg. Grant Date Fair Value (in dollars per share)	$ 44.50	$ 50.54	$ 38.45
Granted, Weighted Av.g Exercise Price (in dollars per share)	$ 62.78	$ 34.24	$ 55.84
Vested, Weighted Avg. Grant Date Fair Value (in dollars per share)	$ 55.84	$ 45.30	$ 33.32
Forfeited, Weighted Avg. Grant Date Fair Value (in dollars per share)	$ 47.32	$ 44.99	$ 42.77
Unvested shares outstanding at December 31, Weighted Avg. Grant Date Fair Value (in dollars per share)	$ 48.73	$ 44.50	$ 50.54
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value	$ 4,013	$ 3,480	$ 3,464
Aggregate Intrinsic Value	6,504	6,019	4,747
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested shares outstanding at January 1, Shares	40,219	36,359	41,715
Granted (in shares)	23,449	20,225	18,053
Vested (in shares)	(19,796)	(14,861)	(21,510)
Forfeited (in shares)	(6,411)	(1,504)	(1,899)
Unvested shares outstanding at December 31, Shares	37,461	40,219	36,359
Unvested shares outstanding at January 1, Weighted Avg. Grant Date Fair Value (in dollars per share)	$ 34.82	$ 35.60	$ 29.37
Granted, Weighted Av.g Exercise Price (in dollars per share)	$ 44.41	$ 31.53	$ 38.57
Vested, Weighted Avg. Grant Date Fair Value (in dollars per share)	$ 38.19	$ 32.41	$ 26.26
Forfeited, Weighted Avg. Grant Date Fair Value (in dollars per share)	$ 36.91	$ 33.36	$ 32.78
Unvested shares outstanding at December 31, Weighted Avg. Grant Date Fair Value (in dollars per share)	$ 38.69	$ 34.82	$ 35.60
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value	756	482	565
Aggregate Intrinsic Value	$ 2,511	$ 1,575	$ 1,131