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Commitment and contingencies variable interest entities (Details 4) - USD ($) $ in Thousands | Sep. 30, 2016 | Jun. 27, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Feb. 07, 2013
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Dakota Prairie Refining, LLC [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Total project costs | $ 300,000 |  |  |  |
Portion of capital commitment | 150,000 |  |  |  |
Partner portion of capital commitment | 75,000 |  |  |  |
Excess capital commitments | 300,000 |  |  |  |
Term loan for project debt financing | 75,000 |  |  |  |
Dakota Prairie Refining, LLC [Member] | Cash and cash equivalents [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, assets |  |  | $ 851 | $ 625 |
Dakota Prairie Refining, LLC [Member] | Accounts receivable [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, assets |  |  | 7,693 | 14,648 |
Dakota Prairie Refining, LLC [Member] | Inventories [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, assets |  |  | 13,176 | 12,354 |
Dakota Prairie Refining, LLC [Member] | Other current assets [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, assets |  |  | 6,215 | 7,125 |
Dakota Prairie Refining, LLC [Member] | Total current assets [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, assets |  |  | 27,935 | 34,752 |
Dakota Prairie Refining, LLC [Member] | Net property, plant and equipment [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, assets |  |  | 425,123 | 428,383 |
Dakota Prairie Refining, LLC [Member] | Other [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, assets |  |  | 9,626 | 5,052 |
Dakota Prairie Refining, LLC [Member] | Total deferred charges and other assets [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, assets |  |  | 9,626 | 5,052 |
Dakota Prairie Refining, LLC [Member] | Total assets [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, assets |  |  | 462,684 | 468,187 |
Dakota Prairie Refining, LLC [Member] | Short-term borrowings [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, liabilities |  |  | 45,500 | 29,500 |
Dakota Prairie Refining, LLC [Member] | Long-term debt due within one year [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, liabilities |  |  | 5,250 | 4,125 |
Dakota Prairie Refining, LLC [Member] | Accounts payable [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, liabilities |  |  | 24,766 | 21,686 |
Dakota Prairie Refining, LLC [Member] | Taxes payable [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, liabilities |  |  | 1,391 | 1,630 |
Dakota Prairie Refining, LLC [Member] | Accrued compensation [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, liabilities |  |  | 938 | 1,059 |
Dakota Prairie Refining, LLC [Member] | Other accrued liabilities [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, liabilities |  |  | 4,953 | 1,217 |
Dakota Prairie Refining, LLC [Member] | Total current liabilities [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, liabilities |  |  | 82,798 | 59,217 |
Dakota Prairie Refining, LLC [Member] | Long-term debt [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, liabilities |  |  | 63,750 | 64,875 |
Dakota Prairie Refining, LLC [Member] | Total liabilities [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Limited liability entity, consolidated, carrying amount, liabilities |  |  | $ 146,548 | $ 124,092 |
Fuel contract [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Variable interest entity, reporting entity involvement, maximum loss exposure, amount | $ 44,100 |  |  |  |
Calumet [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Previous percentage of ownership |  |  |  |  | 50.00%
WBI Energy [Member] |  |  |  |  |
Variable Interest Entities [Line Items] |  |  |  |  |
Previous percentage of ownership |  |  |  |  | 50.00%
Percentage of ownership acquired |  | 50.00% |  |  |

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