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Assets held for sale and discontinued operations Accounting pronouncement reclassification (Details 5) - Restatement adjustment [Member] - Accounting Standards Update 2015-17 [Member] - Exploration and production [Member] - Discontinued operations, held-for-sale or disposed of by sale [Member] $ in Millions | Sep. 30, 2016 USD ($)
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Other current assets [Member] |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |
Reclass to deferred tax asset | $ 47.5
Other current liabilities [Member] |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |
Reclass to deferred tax asset | $ (4.1)

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- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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