v2.4.0.6

Impairments - Fair Value of Impaired Assets and Associated Loss (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Net properties plants and equipment held for use before tax loss | $ 265 | $ 1,604 |
Equity method investments of assets before tax loss | 399 | 645 |
Cost method investments of assets before tax loss | 8 |  |
Net properties plants and equipment held for sale before tax loss |  | 43 |
Before-Tax Loss Included in Discontinued Operations | 471 | 1,699 | 66
Fair value [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Net PP&E held for use | 162 | 307 |
Equity method investments | 274 | 735 |
Cost method investments | 2 |  |
Net PP&E held for sale |  | 23 |
Fair value [Member] | Level 1 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Net PP&E held for use |  |  |
Equity method investments |  |  |
Cost method investments | 2 |  |
Net PP&E held for sale |  | 5 |
Fair value [Member] | Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Net PP&E held for use | 162 | 307 |
Equity method investments | 274 | 735 |
Cost method investments |  |  |
Net PP&E held for sale |  | 18 |
Net PP&E (held for use) [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Before-Tax Loss Included in Discontinued Operations | 1 | 1,508 |
Equity method investments [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Before-Tax Loss Included in Discontinued Operations | 4 |  |
Cost method investments [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Before-Tax Loss Included in Discontinued Operations |  |  |
Net PP&E (held for sale) [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Before-Tax Loss Included in Discontinued Operations |  | $ 43 |

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- Definition Amount of impairment charges attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period. + References No definition available. + Details
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- Definition Equity method investments of assets measured on nonrecurring basis. + References No definition available. + Details
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- Definition Net properties plants and equipment measured on nonrecurring basis held for sale. + References No definition available. + Details
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- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 6 -Subparagraph a -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 AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 6 -Subparagraph a -Footnote 3a -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. + Details
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- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 19 -Subparagraph h -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 323 -SubTopic 10 -Section 35 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=7658923&loc=d3e32787-111569 + Details
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- Definition The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 26 -Subparagraph b -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 958 -SubTopic 225 -Section 45 -Paragraph 11 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6743430&loc=d3e92212-112881 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Impairment -URI http://asc.fasb.org/extlink&oid=6515133 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2420-110228 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2921-110230 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 7, 25 -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. + Details
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- Definition The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2611-110228 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 27, 28, 29, 30 -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. + Details
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