Incentive Plans (Schedule Of Restricted Stock Award Activity) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Restricted Stock Equity Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares/Units, Outstanding at beginning of year	1,512,762
Number of Shares granted	433,311
Forfeitures, number of shares	(80,150)
Awards vested	(517,908)
Number of Shares/Units, Outstanding at end of year	1,348,015	1,512,762
Weighted Average Grant-Date Fair Value, Outstanding at beginning of year	$ 96.22
Weighted Average Grant-Date Fair Value, Shares granted	$ 134.58	$ 113.02	$ 97.52
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 116.50
Weighted Average Grant-Date Fair Value, Shares vested	$ 70.22
Weighted Average Grant-Date Fair Value, Outstanding at end of year	$ 117.09	$ 96.22
Restricted Stock Liability Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares/Units, Outstanding at beginning of year	405,916
Number of Shares granted	250,641
Forfeitures, number of shares	(35,813)
Awards vested	(198,362)
Number of Shares/Units, Outstanding at end of year	422,382