|
Assets and Liabilities with Recurring Fair Value Measurements Fair Value Hierarchy (Details) (USD $)
In Millions, unless otherwise specified |
Jun. 30, 2014
|
Dec. 31, 2013
|
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||||||||||||
| Cash equivalents | $ 636 | [1] | $ 1,134 | [1] | ||||||||
| Margin deposits | 239 | [2] | 261 | [2] | ||||||||
| Commodity futures contracts | 681 | 434 | ||||||||||
| Commodity forward contracts | 296 | [3] | 107 | [3] | ||||||||
| Interest Rate Swap Assets, Fair Value Disclosure | 5 | 9 | ||||||||||
| Total assets | 1,857 | 1,945 | ||||||||||
| Margin deposits held by us posted by our counterparties | 184 | [2],[4] | 5 | [2],[4] | ||||||||
| Commodity futures contracts | 640 | 495 | ||||||||||
| Commodity forward contracts | 184 | [3] | 70 | [3] | ||||||||
| Interest rate swaps | 130 | 129 | ||||||||||
| Liabilities, Fair Value Disclosure | 1,138 | 699 | ||||||||||
|
Fair Value, Inputs, Level 1 [Member]
|
||||||||||||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||||||||||||
| Cash equivalents | 636 | [1] | 1,134 | [1] | ||||||||
| Margin deposits | 239 | 261 | ||||||||||
| Commodity futures contracts | 681 | 434 | ||||||||||
| Commodity forward contracts | 0 | [3] | 0 | [3] | ||||||||
| Interest Rate Swap Assets, Fair Value Disclosure | 0 | 0 | ||||||||||
| Total assets | 1,556 | 1,829 | ||||||||||
| Margin deposits held by us posted by our counterparties | 184 | 5 | ||||||||||
| Commodity futures contracts | 640 | 495 | ||||||||||
| Commodity forward contracts | 0 | [3] | 0 | [3] | ||||||||
| Interest rate swaps | 0 | 0 | ||||||||||
| Liabilities, Fair Value Disclosure | 824 | 500 | ||||||||||
|
Fair Value, Inputs, Level 2 [Member]
|
||||||||||||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||||||||||||
| Cash equivalents | 0 | [1] | 0 | [1] | ||||||||
| Margin deposits | 0 | 0 | ||||||||||
| Commodity futures contracts | 0 | 0 | ||||||||||
| Commodity forward contracts | 256 | [3] | 75 | [3] | ||||||||
| Interest Rate Swap Assets, Fair Value Disclosure | 5 | 9 | ||||||||||
| Total assets | 261 | 84 | ||||||||||
| Margin deposits held by us posted by our counterparties | 0 | 0 | ||||||||||
| Commodity futures contracts | 0 | 0 | ||||||||||
| Commodity forward contracts | 135 | [3] | 52 | [3] | ||||||||
| Interest rate swaps | 130 | 129 | ||||||||||
| Liabilities, Fair Value Disclosure | 265 | 181 | ||||||||||
|
Fair Value, Inputs, Level 3 [Member]
|
||||||||||||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||||||||||||
| Cash equivalents | 0 | [1] | 0 | [1] | ||||||||
| Margin deposits | 0 | 0 | ||||||||||
| Commodity futures contracts | 0 | 0 | ||||||||||
| Commodity forward contracts | 40 | [3] | 32 | [3] | ||||||||
| Interest Rate Swap Assets, Fair Value Disclosure | 0 | 0 | ||||||||||
| Total assets | 40 | 32 | ||||||||||
| Margin deposits held by us posted by our counterparties | 0 | 0 | ||||||||||
| Commodity futures contracts | 0 | 0 | ||||||||||
| Commodity forward contracts | 49 | [3] | 18 | [3] | ||||||||
| Interest rate swaps | 0 | 0 | ||||||||||
| Liabilities, Fair Value Disclosure | $ 49 | $ 18 | ||||||||||
|
||||||||||||