Consolidated Balance Sheets Parentheticals (Parentheticals) (USD $) In Millions, except Share data, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Allowance for doubtful accounts	$ 34	$ 32
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	$ 9,488	$ 9,089
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	343,333,333	343,333,333
Common stock, shares issued	238,374,738	234,688,063
Common stock, shares outstanding	238,374,738	234,688,063