Derivative Instruments (Details 4) (USD $) In Millions | 3 Months Ended | 9 Months Ended | |||||||
|---|---|---|---|---|---|---|---|---|---|
Sep. 30, 2011 | Sep. 30, 2010 | Sep. 30, 2011 | Sep. 30, 2010 | ||||||
| Derivatives included in OCI and AOCI [Line Items] | |||||||||
| Gain (loss) recognized in OCI (effective portion) | $ (94) | $ 53 | $ (36) | $ 105 | |||||
| Gain (loss) reclassified from AOCI into income (effective portion) | 20 | 12 | (24) | (10) | |||||
| Gain (loss) reclassified from AOCI into income (ineffective portion) | (2) | (1) | (2) | ||||||
Interest Rate Swaps | |||||||||
| Derivatives included in OCI and AOCI [Line Items] | |||||||||
| Gain (loss) recognized in OCI (effective portion) | 9 | 8 | (27) | 87 | |||||
| Gain (loss) reclassified from AOCI into income (effective portion) | 27 | 62 | 106 | [1] | 162 | ||||
| Gain (loss) reclassified from AOCI into income (ineffective portion) | (1) | (1) | |||||||
Commodity instruments | |||||||||
| Derivatives included in OCI and AOCI [Line Items] | |||||||||
| Gain (loss) recognized in OCI (effective portion) | (103) | 45 | (9) | 18 | |||||
| Gain (loss) reclassified from AOCI into income (effective portion) | (7) | (50) | (130) | [2] | (172) | ||||
| Gain (loss) reclassified from AOCI into income (ineffective portion) | $ (1) | $ (2) | |||||||
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