Share-Based Awards (Summary Of Stock Appreciation Right Transactions) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding, beginning of period	6,311,000
Weighted-Average Price, Options outstanding, beginning of period	$ 37
Options granted	480,000
Weighted-Average Price, Options granted	$ 45
Options exercised	1,666,000
Weighted-Average Price, Options exercised	$ 28
Options forfeited	665,000
Weighted-Average Price, Options forfeited	$ 52
Options outstanding, end of period	4,460,000	6,311,000
Weighted-Average Price, Options outstanding, end of period	$ 38	$ 37
Exercisable, end of period	3,065,000
Weighted-Average Price, Exercisable, end of period	$ 42
Weighted-average Aggregate weighted-average fair value of options	$ 14	$ 15	$ 8
Stock Appreciation Rights (SAR's) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding, beginning of period	273,000
Weighted-Average Price, Options outstanding, beginning of period	$ 21
Options granted	21,000
Weighted-Average Price, Options granted	$ 45
Options exercised	40,000
Weighted-Average Price, Options exercised	$ 22
Options forfeited	1,000
Weighted-Average Price, Options forfeited	$ 22
Options outstanding, end of period	253,000
Weighted-Average Price, Options outstanding, end of period	$ 23
Exercisable, end of period	160,000