Stock-Based Compensation (Summary Of Stock Option Activity) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation [Abstract]
Number of options outstanding, Beginning balance	10,459,418
Options outstanding, Weighted-average exercise price, Beginning balance	$ 75.46
Number of options granted	552,400
Options granted, Weighted-average exercise price	$ 71.30
Number of options exercised	(1,407,159)
Options exercised, Weighted-average exercise price	$ 44.46
Number of Options forfeited/expired	46,313
Options forfeited/expired, Weighted-average exercise price	$ 76.83
Number of options outstanding, Ending balance	9,558,346	10,459,418
Options outstanding, Weighted-average exercise price, Ending balance	$ 79.77	$ 75.46
Options outstanding, Aggregate intrinsic value	$ 0
Weighted-Average Contractual Life, Options outstanding	4 years 7 months 7 days
Options exercisable, Number of Options	8,442,157
Options exercisable, Weighted-Average Exercise Price	$ 80.61
Weighted-Average Contractual Life, Options exercisable	5 years 1 month 6 days
Weighted-average grant-date fair value of options granted	$ 9.42	$ 11.48	$ 13.18