Statement of Consolidated Shareholders' Equity (Parenthetical) (Unaudited) (USD $) In Millions, except Per Share data	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Comprehensive income:
Income tax expense (benefit) to commodity hedges	$ 121	$ 152
Dividends:
Common stock, dividends, per share	$ 0.45	$ 0.45
Comprehensive Income
Comprehensive income:
Income tax expense (benefit) to commodity hedges	121	152
Retained Earnings
Dividends:
Common stock, dividends, per share	$ 0.45	$ 0.45
Accumulated Other Comprehensive Income (Loss)
Comprehensive income:
Income tax expense (benefit) to commodity hedges	$ 121	$ 152