|
Financial Instruments - Narrative (Details) (USD $)
In Millions, unless otherwise specified
|
3 Months Ended |
12 Months Ended |
|
Mar. 31, 2015
Contract
|
Mar. 31, 2014
|
Dec. 31, 2014
MBbls
|
| Credit Derivatives [Line Items] |
|
|
|
| Number of contracts that are designated as accounting hedges |
0 |
|
|
| Derivative (loss) gain on oil and natural gas financial derivative instruments |
$ 203 |
$ (135) |
|
| Interest rate derivative instruments | Derivatives not designated as accounting hedges |
|
|
|
| Credit Derivatives [Line Items] |
|
|
|
| Monetary notional amount |
600 |
|
|
| Net liability related to interest rate derivatives (less than $1 million) |
1 |
|
|
| Net asset related to interest rate derivatives |
|
|
3 |
| Interest expense related to the change in fair market value and cash settlements of interest rate derivative instruments |
$ 4 |
$ 1 |
|
| Oil derivatives | Fixed Price Swaps | Derivatives not designated as accounting hedges |
|
|
|
| Credit Derivatives [Line Items] |
|
|
|
| Nonmonetary notional amount (in MBbls or gal) |
36,000 |
|
37,000 |
| Natural gas derivatives | Fixed Price Swaps | Derivatives not designated as accounting hedges |
|
|
|
| Credit Derivatives [Line Items] |
|
|
|
| Nonmonetary notional amount (in Btu) |
54,000 |
|
69,000 |
| Propane derivatives | Fixed Price Swaps | Derivatives not designated as accounting hedges |
|
|
|
| Credit Derivatives [Line Items] |
|
|
|
| Nonmonetary notional amount (in MBbls or gal) |
35,000,000 |
|
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