v2.4.0.6

Fair Value Fair Value of Derivative Contracts (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 31, 2013 | Mar. 31, 2012 | Mar. 31, 2013 Estimate of Fair Value [Member] Commodity Contract [Member] | Dec. 31, 2012 Estimate of Fair Value [Member] Commodity Contract [Member] | Mar. 31, 2013 Estimate of Fair Value [Member] Interest Rate Swap [Member] | Dec. 31, 2012 Estimate of Fair Value [Member] Interest Rate Swap [Member] | Mar. 31, 2013 Quoted prices in active markets for identical assets (Level 1) [Member] Commodity Contract [Member] | Dec. 31, 2012 Quoted prices in active markets for identical assets (Level 1) [Member] Commodity Contract [Member] | Mar. 31, 2013 Quoted prices in active markets for identical assets (Level 1) [Member] Interest Rate Swap [Member] | Dec. 31, 2012 Quoted prices in active markets for identical assets (Level 1) [Member] Interest Rate Swap [Member] | Mar. 31, 2013 Significant other observable inputs (Level 2) [Member] Commodity Contract [Member] | Dec. 31, 2012 Significant other observable inputs (Level 2) [Member] Commodity Contract [Member] | Mar. 31, 2013 Significant other observable inputs (Level 2) [Member] Interest Rate Swap [Member] | Dec. 31, 2012 Significant other observable inputs (Level 2) [Member] Interest Rate Swap [Member] | Mar. 31, 2013 Significantunobservable inputs (Level 3) [Member] Commodity Contract [Member] | Dec. 31, 2012 Significantunobservable inputs (Level 3) [Member] Commodity Contract [Member] | Mar. 31, 2013 Significantunobservable inputs (Level 3) [Member] Interest Rate Swap [Member] | Dec. 31, 2012 Significantunobservable inputs (Level 3) [Member] Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative Assets |  |  | $ 78 | $ 107 | $ 579 | $ 665 | $ 2 | $ 3 | $ 0 | $ 0 | $ 57 | $ 76 | $ 579 | $ 665 | $ 19 | $ 28 | $ 0 | $ 0
Fair Value, Assets Liabilites Net, Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning of Period | (155) | 7 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total gains (losses), Included in earnings | 5 | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total gains (losses), Included in other comprehensive income | (1) | (22) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchases | 0 | 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Settlements | 9 | 7 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
End of Period | (142) | (3) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
The amount of total gains or (losses) for the period included in earnings attributable to the change in unrealized gains or (losses) relating to assets held at the reporting date | (1) | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Liability fair value, derivative |  |  | $ (217) | $ (212) | $ (3) | $ (1) | $ (17) | $ (3) | $ 0 | $ 0 | $ (39) | $ (26) | $ (3) | $ (1) | $ (161) | $ (183) | $ 0 | $ 0

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- Definition Fair values as of the balance sheet date of all assets resulting from contracts that meet the criteria of being accounted for as derivative instruments, net of the effects of master netting arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FIN39-1 -Paragraph 10A, 10B -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13433-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 4, 17 -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 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13495-108611 + Details
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- Definition Derivative instrument obligations meeting the definition of a liability which the Company is a party to as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 15 -Paragraph 83 -URI http://asc.fasb.org/extlink&oid=6913464&loc=d3e34841-113949 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 10 -Subparagraph i -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 6 -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 the amount of the total change in unrealized (holding) gains or losses for the period which are included in the statement of income (or changes in net assets) in investment income. Such unrealized (holding) gains or losses relate to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph d -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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