Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Stockholders’ equity-
Common stock, par value (in dollars per share)	$ 0.1	$ 0.1
Common stock, shares authorized	700,000,000	700,000,000
Common stock, shares outstanding	511,445,350	445,334,111
Par Value, in dollars per share	$ 100
Preferred stock, shares authorized	5,000,000
Customer
Receivables-
Allowance for uncollectible accounts	$ 49	$ 49
Other
Receivables-
Allowance for uncollectible accounts	$ 2	$ 1
Series A Convertible Preferred Stock
Stockholders’ equity-
Preferred stock shares issued	1,616,000
Preferred stock shares outstanding	704,589