Employee Benefit Plans (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Description of Direction and Pattern of Change for Assumed Health Care Cost Trend Rate	0.05
Defined Benefit Plan, Other Information	0.0885
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	$ 6,300,000,000	$ 3,300,000,000
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year	163,000,000
Other Labor-related Expenses	(264,000,000)	(313,000,000)	0
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year	700,000,000
Assumed Health care plan pre age	65
Deferred Compensation Cash-based Arrangements, Liability, Current	$ 264,000,000	$ 313,000,000
Assumed Health care plan post age	65