|
Assets and Liabilities with Recurring Fair Value Measurements (Details) (USD $)
In Millions, unless otherwise specified |
3 Months Ended | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Mar. 31, 2012
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Mar. 31, 2011
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Dec. 31, 2011
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| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||||||||||||||||||||
| Transfers into level 3 | $ 0 | [1],[2] | $ 0 | [1],[2] | ||||||||||||||||
| Cash equivalents | 1,212 | [3] | 1,415 | [3] | ||||||||||||||||
| Margin deposits | 165 | [4] | 140 | [4] | ||||||||||||||||
| Commodity futures contracts | 1,439 | 1,043 | ||||||||||||||||||
| Commodity forward contracts | 142 | [5] | 111 | [5] | ||||||||||||||||
| Interest rate swaps | 8 | 10 | ||||||||||||||||||
| Total assets | 2,966 | 2,719 | ||||||||||||||||||
| Margin deposits held by us posted by our counterparties | 111 | [4],[6] | 34 | [4],[6] | ||||||||||||||||
| Commodity futures contracts | 1,141 | 899 | ||||||||||||||||||
| Commodity forward contracts | 248 | [5] | 204 | [5] | ||||||||||||||||
| Interest rate swaps | 169 | 320 | ||||||||||||||||||
| Total liabilities | 1,669 | 1,457 | ||||||||||||||||||
| Transfers out of level 3 | (4) | [2],[7] | 0 | [2],[7] | ||||||||||||||||
|
Fair Value, Inputs, Level 1 [Member]
|
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| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||||||||||||||||||||
| Cash equivalents | 1,212 | [3] | 1,415 | [3] | ||||||||||||||||
| Margin deposits | 165 | 140 | ||||||||||||||||||
| Commodity futures contracts | 1,439 | 1,043 | ||||||||||||||||||
| Commodity forward contracts | 0 | [5] | 0 | [5] | ||||||||||||||||
| Interest rate swaps | 0 | 0 | ||||||||||||||||||
| Total assets | 2,816 | 2,598 | ||||||||||||||||||
| Margin deposits held by us posted by our counterparties | 111 | 34 | ||||||||||||||||||
| Commodity futures contracts | 1,141 | 899 | ||||||||||||||||||
| Commodity forward contracts | 0 | [5] | 0 | [5] | ||||||||||||||||
| Interest rate swaps | 0 | 0 | ||||||||||||||||||
| Total liabilities | 1,252 | 933 | ||||||||||||||||||
|
Fair Value, Inputs, Level 2 [Member]
|
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| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||||||||||||||||||||
| Cash equivalents | 0 | [3] | 0 | [3] | ||||||||||||||||
| Margin deposits | 0 | 0 | ||||||||||||||||||
| Commodity futures contracts | 0 | 0 | ||||||||||||||||||
| Commodity forward contracts | 107 | [5] | 74 | [5] | ||||||||||||||||
| Interest rate swaps | 8 | 10 | ||||||||||||||||||
| Total assets | 115 | 84 | ||||||||||||||||||
| Margin deposits held by us posted by our counterparties | 0 | 0 | ||||||||||||||||||
| Commodity futures contracts | 0 | 0 | ||||||||||||||||||
| Commodity forward contracts | 230 | [5] | 184 | [5] | ||||||||||||||||
| Interest rate swaps | 169 | 320 | ||||||||||||||||||
| Total liabilities | 399 | 504 | ||||||||||||||||||
|
Fair Value, Inputs, Level 3 [Member]
|
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| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||||||||||||||||||||
| Cash equivalents | 0 | [3] | 0 | [3] | ||||||||||||||||
| Margin deposits | 0 | 0 | ||||||||||||||||||
| Commodity futures contracts | 0 | 0 | ||||||||||||||||||
| Commodity forward contracts | 35 | [5] | 37 | [5] | ||||||||||||||||
| Interest rate swaps | 0 | 0 | ||||||||||||||||||
| Total assets | 35 | 37 | ||||||||||||||||||
| Margin deposits held by us posted by our counterparties | 0 | 0 | ||||||||||||||||||
| Commodity futures contracts | 0 | 0 | ||||||||||||||||||
| Commodity forward contracts | 18 | [5] | 20 | [5] | ||||||||||||||||
| Interest rate swaps | 0 | 0 | ||||||||||||||||||
| Total liabilities | $ 18 | $ 20 | ||||||||||||||||||
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