Supplemental Cash Flow Information (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012
Components of operating assets and liabilities
Decrease (increase) in restricted cash	$ 275	$ 4,508
Decrease (increase) in accounts receivable	(12,512)	(71,647)
Decrease (increase) in receivable from affiliates	(2,416)	648
Decrease (increase) in inventories	(237)	9,944
Decrease (increase) in derivatives and margin deposits	972	702
Decrease (increase) in other current assets	839	3,825
Decrease (increase) in other assets	266	2,259
Increase (decrease) in accounts payable and accrued liabilities	7,229	42,802
Increase (decrease) in payable to affiliates	2	(5,622)
Increase (decrease) in payables to pre-petition creditors	(424)	(4,360)
Increase (decrease) in other noncurrent liabilities	(3,323)	(1,289)
Total changes in operating assets and liabilities	$ 9,329	$ 18,230

Increase (decrease) in derivatives and margin deposits

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- Definition

Increase (decrease) in payables to pre-petition creditors.

+ References

No definition available.

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- Definition

The increase (decrease) during the reporting period in receivables to be collected from an entity that is controlling, under the control of, or within the same control group as the reporting entity by means of direct or indirect ownership.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

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- Definition

The increase (decrease) during the reporting period in the amounts payable to vendors for goods and services received and the amount of obligations and expenses incurred but not paid.

+ References

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- Definition

The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

+ References

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The increase (decrease) in obligations owed to an entity that is controlling, under the control of, or within the same control group as the reporting entity by means of direct or indirect ownership.

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- Definition

The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.

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The increase (decrease) during the reporting period of all assets and liabilities used in operating activities.

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- Definition

The increase (decrease) during the reporting period in other current operating assets not separately disclosed in the statement of cash flows.

+ References

No definition available.

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- Definition

The increase (decrease) during the reporting period in other noncurrent operating liabilities not separately disclosed in the statement of cash flows.

+ References

No definition available.

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- Definition

The increase (decrease) during the reporting period in other assets used in operating activities not separately disclosed in the statement of cash flows. May include changes in other current assets, other noncurrent assets, or a combination of other current and noncurrent assets.

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- Definition

The net cash inflow or outflow for the increase (decrease) associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as investing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3179-108585

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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