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Noncontrolling interest (Details 3) - USD ($) $ in Millions |  |  | 3 Months Ended
--- | --- | --- | ---
Jun. 27, 2016 | Jun. 24, 2016 | Mar. 31, 2017
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% | 50.00% |
Operating expense [Member] | Refining [Member] |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Reversal of an accrual |  |  | $ 7.0
Operating expense - after tax [Member] | Refining [Member] |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Reversal of an accrual |  |  | $ 4.3

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- Definition Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 5A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=77990344&loc=SL6759159-111685 + Details
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