Pension and Other Employee Benefits (Schedule of Fair Value Measurements of the Company's Pension Plan Assets By Asset Category And By Level) (Details) (USD $)
In Millions, unless otherwise specified
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets $ 1,169 $ 752 $ 627
Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 16,733 14,931  
Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 6,575 6,772  
Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 8,989 7,407  
Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 1,169 752  
US Equities [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 4,626 4,590  
US Equities [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 1,817 2,804  
US Equities [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 2,809 1,786  
US Equities [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Developed [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 2,350 1,860  
Developed [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 1,834 1,520  
Developed [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 516 340  
Developed [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Emerging [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 658 471  
Emerging [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 553 410  
Emerging [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 105 61  
Emerging [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
US Government Agencies Debt Securities [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 69 540  
US Government Agencies Debt Securities [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 69 525  
US Government Agencies Debt Securities [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 15  
US Government Agencies Debt Securities [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Investment grade bonds [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 1,989 1,515  
Investment grade bonds [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 69  
Investment grade bonds [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 1,989 1,446  
Investment grade bonds [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Non-Investment Grade Bonds [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 336 458  
Non-Investment Grade Bonds [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Non-Investment Grade Bonds [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 336 458  
Non-Investment Grade Bonds [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Foreign Government Debt Securities [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 181 112  
Foreign Government Debt Securities [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 181 0  
Foreign Government Debt Securities [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 112  
Foreign Government Debt Securities [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Core Fixed Income [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 1,519 890  
Core Fixed Income [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 1,281 619  
Core Fixed Income [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 238 271  
Core Fixed Income [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Global multi sector fixed income investments [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 202 341  
Global multi sector fixed income investments [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 139  
Global multi sector fixed income investments [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 202 202  
Global multi sector fixed income investments [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Fixed Income Funds [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 67 53 53
Fixed Income Funds [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 297 502  
Fixed Income Funds [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Fixed Income Funds [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 230 449  
Fixed Income Funds [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 67 53  
Securitized fixed income securities [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 480 307  
Securitized fixed income securities [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Securitized fixed income securities [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 480 307  
Securitized fixed income securities [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Cash and Cash Equivalents [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 868 1,093  
Cash and Cash Equivalents [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 333 485  
Cash and Cash Equivalents [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 535 608  
Cash and Cash Equivalents [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Relative Value [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 23 0
Relative Value [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 358 306  
Relative Value [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Relative Value [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 358 283  
Relative Value [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 23  
Hedge Funds, Event Driven [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 72 57 39
Hedge Funds, Event Driven [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 203 275  
Hedge Funds, Event Driven [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Hedge Funds, Event Driven [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 131 218  
Hedge Funds, Event Driven [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 72 57  
Hedge Funds, Equity [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 5 0 22
Hedge Funds, Equity [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 118 151  
Hedge Funds, Equity [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Hedge Funds, Equity [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 113 151  
Hedge Funds, Equity [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 5 0  
Hedge Funds, Global Opportunity [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 103 22 21
Hedge Funds, Global Opportunity [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 1,065 785  
Hedge Funds, Global Opportunity [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Hedge Funds, Global Opportunity [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 962 763  
Hedge Funds, Global Opportunity [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 103 22  
Multi Strategy Funds [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 501 193  
Multi Strategy Funds [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 501 193  
Multi Strategy Funds [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Multi Strategy Funds [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Private Equity Funds [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 406 301 252
Private Equity Funds [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 406 301  
Private Equity Funds [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Private Equity Funds [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Private Equity Funds [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 406 301  
Private Real Estate Funds [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 299 182 156
Private Real Estate Funds [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 299 182  
Private Real Estate Funds [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Private Real Estate Funds [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Private Real Estate Funds [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 299 182  
Insurance Contracts [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 25 25 23
Insurance Contracts [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 25 25  
Insurance Contracts [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Insurance Contracts [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Insurance Contracts [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 25 25  
Cash collateral for borrowed securities [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets (15) (63)  
Cash collateral for borrowed securities [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Cash collateral for borrowed securities [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets (15) (63)  
Cash collateral for borrowed securities [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Other Funds [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 192 89 61
Other Funds [Member] | Domestic Pension Plan [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 198 97  
Other Funds [Member] | Domestic Pension Plan [Member] | Level 1 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 6 8  
Other Funds [Member] | Domestic Pension Plan [Member] | Level 2 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets 0 0  
Other Funds [Member] | Domestic Pension Plan [Member] | Level 3 [Member]
     
Defined Benefit Plan, Fair Value of Plan Assets $ 192 $ 89