Supplemental Cash Flow Information - Operating assets and liabilities (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Components of operating assets and liabilities
Decrease (increase) in restricted cash	$ 342	$ (2,585)
Decrease (increase) in accounts receivable	56,863	(58,879)
Decrease (increase) in receivable from affiliates	1,663	14,992
Decrease (increase) in inventories	(25,857)us-gaap_IncreaseDecreaseInInventories	3,715us-gaap_IncreaseDecreaseInInventories
Decrease (increase) in derivatives and margin deposits	(2,356)	(546)
Decrease (increase) in other current assets	2,280	1,636
Decrease (increase) in other assets	(628)	(33)
Increase (decrease) in accounts payable and accrued liabilities	(51,435)	49,754
Increase (decrease) in payable to affiliates	2,728	(24,075)
Increase (decrease) in payables to pre-petition creditors	(2)	(2)
Increase (decrease) in other noncurrent liabilities	95	(2,525)
Total changes in operating assets and liabilities	$ (16,307)	$ (18,548)

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 Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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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.

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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.

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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.

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No definition available.

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- Definition

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

+ References

No definition available.

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

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No definition available.

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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=31042434&loc=d3e3179-108585

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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-Topic 230

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-Section 45

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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