Common Stock (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Class of Stock [Line Items]
Contribution of Common stock to the Pension Plan Value	$ 80	$ 100
Days to Contrbute Common Stock to Pension Plan	4 days
Maximum Total Funded Debt to Total Capitalization Ratio	0.65
Minimum Total Funded Debt to Total Capitilization Ration Denominator	1
Line of Credit Facility, Dividend Restrictions	239
Retained Earnings (Accumulated Deficit)	3,944	3,750
Limitations with Respect of Company's Ability to Pay Dividends	0
Retained Earnings [Member]
Class of Stock [Line Items]
Retained Earnings (Accumulated Deficit)	$ 4,000