Pension and Other Postretirement Benefits (Details - Assumptions and 401(k) Plans) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Benefit payments including expected future services [Abstract]
Expense for matching contributions in the 401K plan	$ 78,000,000	$ 72,000,000	$ 69,000,000
Pension Benefits [Member]
Assumptions for pension and other postretirement benefits [Abstract]
Discount rate: Benefit obligation	3.50%	4.00%
Discount rate: Benefit cost	4.00%	5.00%
Expected long-term return on plan assets: Benefit cost	8.00%	8.00%
Recognition Period For Market Fluctuation Impacts On Pension Cost	5 years
Defined Benefit Plan Market Related Value Of Pension Plan Assets	3,500,000,000
Defined Benefit Plan Market Value Of Pension Plan Assets	3,600,000,000
Benefit payments including expected future services [Abstract]
Paid after one year	396,000,000
Paid after two years	342,000,000
Paid after three years	333,000,000
Paid after four years	331,000,000
Paid after five years	332,000,000
Paid in six to ten years	1,630,000,000
Other Postretirement Benefits [Member]
Assumptions for pension and other postretirement benefits [Abstract]
Discount rate: Benefit obligation	3.25%	3.75%
Discount rate: Benefit cost	3.75%	4.75%
Expected long-term return on plan assets: Benefit cost	5.00%	5.00%
Benefit payments including expected future services [Abstract]
Paid after one year	35,000,000
Paid after two years	36,000,000
Paid after three years	36,000,000
Paid after four years	35,000,000
Paid after five years	34,000,000
Paid in six to ten years	$ 149,000,000