2.4.0.82119100 - Disclosure - Income and Mining Tax Benefittruefalsefalse1false falsefalseD2013Q2YTDhttp://www.sec.gov/CIK0001415020duration2013-01-01T00:00:002013-06-30T00:00:001true 1us-gaap_IncomeTaxDisclosureAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Income Tax Disclosure [Abstract]2false 2us-gaap_IncomeTaxDisclosureTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;padding-bottom:10px;padding-top:10px;font-size:10pt;">Income and Mining Tax Expense (Benefit)</div><div style="line-height:120%;text-align:left;text-indent:30px;font-size:10pt;">Income and mining taxes for the three months ended June 30, 2013 and 2012 was an expense of $2.0 million and a benefit of $10.8 million, respectively. Income and mining taxes for the six months ended June 30, 2013 and 2012 was a benefit of $1.2 million and $22.9 million, respectively. The tax expense and benefit for the three and six months ended June 30, 2013, respectively, differs from the tax that would result from applying the Canadian federal and provincial income tax rates primarily due to three items: the US percentage depletion benefit; the pre-tax Endako Mine book loss, which has no tax benefit as a result of a valuation allowance recognized, in part, as a result of the asset impairment in the fourth quarter of 2012; and the reduction of a valuation allowance, in part, as a result of the tax treatment of interest expense. The tax benefit for the three and six months ended June 30, 2012 differs from the tax that would result from applying the Canadian federal and provincial income tax rates primarily due to the US percentage depletion benefit and the pre-tax book loss, attributable primarily to Canadian operations. The tax benefit for the six months ended June 30, 2012 was also impacted by an immaterial correction of $1.8 million related to the British Columbia mineral tax associated with TCM's share of the expansion costs at the Endako Mine. The adjustment relates to the three months ended December 31, 2011.</div></div>falsefalsefalsenonnum:textBlockItemTypenaThe entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Article 4 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319 Reference 5: 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=6907707&loc=d3e32537-109319 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319 false0Income and Mining Tax BenefitfalseIncome and Mining Tax BenefitUnKnownUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.thompsoncreekmetals.com/role/IncomeAndMiningTaxBenefit12