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

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- Definition The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-BRD -Paragraph 80 -Subparagraph Exhibit 4-8, 3 -IssueDate 2006-05-01 -Chapter 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 + Details
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- Definition The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-BRD -Paragraph 80 -Subparagraph Exhibit 4-8, 3 -IssueDate 2006-05-01 -Chapter 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 + Details
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