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Noncontrolling interest (Details 3) - USD ($) $ in Millions | Mar. 31, 2017 | Jun. 27, 2016 | Feb. 07, 2013
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Dakota Prairie Refining, LLC [Member] | WBI Energy [Member] |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Previous percentage of ownership |  |  | 50.00%
Percentage of ownership acquired |  | 50.00% |
Dakota Prairie Refining, LLC [Member] | Calumet [Member] |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Previous percentage of ownership |  |  | 50.00%
Refining [Member] |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Reversal of a liability accrual | $ 7.0 |  |
Reversal of a liability accrual, net of tax | $ 4.3 |  |

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