v2.4.0.6
Summary of Significant Accounting Policies (Details) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Dec. 31, 2011
Restricted Cash and Cash Equivalents Items [Line Items]          
Current $ 163   $ 163   $ 139
Non-current 63   63   55
Total 226   226   194
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract]          
Cash and cash equivalents subject to project finance facilities and lease agreements 211   211   306
Held-to-maturity Securities, Restricted 24   24   25
Interest Costs Capitalized 10 6 27 17  
Inventory 269   269   294
Treasury Stock, Value, Acquired, Cost Method     308    
Adjustments Related to Tax Withholding for Share-based Compensation     6    
Accounting Policies [Abstract]          
Operating Leases, Future Minimum Payments Receivable, Current 114   114    
Operating Leases, Future Minimum Payments Receivable, in Two Years 527   527    
Operating Leases, Future Minimum Payments Receivable, in Three Years 452   452    
Operating Leases, Future Minimum Payments Receivable, in Four Years 461   461    
Operating Leases, Future Minimum Payments Receivable, in Five Years 375   375    
Operating Leases, Future Minimum Payments Receivable, Thereafter 2,270   2,270    
Operating Leases, Future Minimum Payments Receivable 4,199   4,199    
Debt Service
          
Restricted Cash and Cash Equivalents Items [Line Items]          
Current 22   22   11
Non-current 42   42   42
Total 64   64   53
Rent Reserve
          
Restricted Cash and Cash Equivalents Items [Line Items]          
Current 3   3   0
Non-current 0   0   0
Total 3   3   0
Construction Major Maintenance
          
Restricted Cash and Cash Equivalents Items [Line Items]          
Current 37   37   33
Non-current 11   11   10
Total 48   48   43
Security Project Insurance
          
Restricted Cash and Cash Equivalents Items [Line Items]          
Current 101   101   79
Non-current 8   8   0
Total 109   109   79
Other
          
Restricted Cash and Cash Equivalents Items [Line Items]          
Current 0   0   16
Non-current 2   2   3
Total $ 2   $ 2   $ 19