Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Held-to-maturity Securities, Current Short-term investments Accounts Receivable, Net, Current Accounts receivable-trade Due from Related Parties, Current Accounts receivable-related parties Product inventory Product Inventory, Net This element represents carrying amount as of balance sheet date of finished goods, work-in-process and stockpiled ore, net of all valuation and other allowances. Other Inventory, Supplies Material and supplies inventory Prepaid expense and other current assets Prepaid Expenses and Other Assets, Current This element represents amounts paid in advance for capitalized costs that will be expensed with the passage of time or the occurrence of a triggering event, and will be charged against earnings within one year or the normal operating cycle, if longer and other current assets not otherwise defined in the taxonomy. Income Taxes Receivable, Current Income tax receivable Assets, Current Total current assets Property, Plant and Equipment, Net Property, plant and equipment, net Restricted Cash and Cash Equivalents, Noncurrent Restricted cash Deposits Assets, Noncurrent Reclamation deposits Goodwill. Goodwill Other Assets, Noncurrent Other assets Assets Total assets Accounts Payable and Accrued Liabilities, Current Accounts payable and accrued liabilities Accrued Income Taxes, Current Income and mining taxes payable Long-term Debt, Current Maturities Current portion of long-term debt Deferred Tax Liabilities, Current Deferred income tax liabilities Liabilities, Current Total current liabilities Long-term Debt, Excluding Current Maturities Long-term debt Other Liabilities, Noncurrent Other liabilities Common Stock Warrant Derivatives Common stock warrant derivatives (Note 8d) Equity-linked financial instrument not indexed to own stock as strike price is denominated in a currency other than the issuers. These instruments are denominated in the Canadian dollar and are required to be treated as a derivative liability with changes in fair value recorded to earnings. Deferred Tax Liabilities, Noncurrent Deferred income tax liabilities Liabilities Total liabilities Common Stock, Value, Issued Common stock, no-par, 165,189,873 and 139,511,257 shares issued and outstanding, as of December 31, 2010 and 2009, respectively Additional paid-in-capital Additional Paid in Capital, Common Stock Retained Earnings (Accumulated Deficit) Retained earnings Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive income Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total shareholders' equity Balances Balances Liabilities and Stockholders' Equity Total liabilities and shareholders' equity Commitments and Contingencies. Commitments and contingencies (Note 16) Other Liabilities, Current Other liabilities Common Stock, No Par Value Common stock, no-par value (in dollars per share) Common Stock, Shares, Outstanding Common stock, shares outstanding Common Stock, Shares, Issued Common stock, shares issued CONSOLIDATED BALANCE SHEETS Current Income Tax Expense (Benefit) Current Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Cumulative Effects of Changes in Accounting Principles, Noncontrolling Interest Income (loss) before income and mining taxes Nonoperating Income (Expense) Total other (income) and expense Other Nonoperating Income (Expense) Other Change in Fair Value of Common Stock Warrant Derivatives This element represents unrealized gain (loss) arising from change in fair value of common stock warrant derivatives, recognized in earnings during the reporting period. Change in fair value of common stock warrants (Note 8d) Change in fair value of warrants Investment Income, Interest Interest income Foreign Currency Transaction Gain (Loss), before Tax (Gain) loss on foreign exchange Goodwill, Impairment Loss Goodwill impairment Goodwill impairment Operating Income (Loss) OPERATING INCOME Costs and Expenses Total costs and expenses Exploration. Expenditures related in the search for mineral properties. These may relate to exploration expenditures at Green field sites (sites where the company does not have any mineral deposits that are already being mined or developed). Exploration General and Administrative Expense General and administrative Accretion expense Asset Retirement Obligation, Accretion Expense Depreciation, Depletion and Amortization Depreciation, depletion and amortization Selling and Marketing Expense Selling and marketing Operating expenses Operating Expense This element represents cost of sales or services and other recurring costs associated with normal operations. Also includes, changes to the fair values of the embedded derivatives related to molybdenum purchases. Weighted Average Number of Shares Outstanding, Diluted Diluted (in shares) Weighted Average Number of Shares Outstanding, Basic Basic (in shares) Earnings Per Share, Diluted Diluted (in dollars per share) Earnings Per Share, Basic Basic (in dollars per share) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest NET INCOME (LOSS) Net income (loss) Income Tax Expense (Benefit) Total Income and mining tax expense Deferred Income Tax Expense (Benefit) Deferred Deferred income taxes (benefit) Revenues Total revenues Tolling, calcining and other Tolling Calcining and Other Revenue This element represents revenue generated during the period from tolling, calcining and other activities, not otherwise defined in the taxonomy. Molybdenum sales Molybdenum Sales This element represents revenue generated during the period from sale of molybdenum. Also includes, changes to the fair value of embedded derivatives related to molybdenum sales agreements. Revenues [Abstract] REVENUES Costs and Expenses [Abstract] COST AND EXPENSES Nonoperating Income (Expense) [Abstract] OTHER (INCOME) EXPENSES Earnings Per Share [Abstract] NET INCOME (LOSS) PER SHARE Weighted Average Number of Shares Outstanding, Diluted [Abstract] Weighted average number of common shares Income Tax Expense (Benefit) [Abstract] Income and mining taxes (benefit) Payments of Debt Issuance Costs Debt issuance costs Repayments of Long-term Debt Repayment of debt Proceeds from Issuance of Long-term Debt Proceeds from issuance of debt Net Cash Provided by (Used in) Operating Activities [Abstract] OPERATING ACTIVITIES Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Items not affecting cash: Net Cash Provided by (Used in) Investing Activities [Abstract] INVESTING ACTIVITIES Net Cash Provided by (Used in) Financing Activities [Abstract] FINANCING ACTIVITIES Supplemental Cash Flow Information Related Text Supplementary cash flow information (Note 21) CONSOLIDATED STATEMENTS OF CASH FLOWS Reclamation (deposit) refund Payments for Reclamation Deposits This element represents cash outflow associated with reclamation deposits. Proceeds from Reclamation Refund Reclamation refund The cash inflow associated with the reclamation refund . Amortization of Financing Costs Share-based Compensation Stock-based compensation Unrealized Gain (Loss) on Derivatives Unrealized loss (gain) on derivative instruments Increase (Decrease) in Operating Capital Change in working capital accounts (Note 21) Net Cash Provided by (Used in) Operating Activities Cash generated by operating activities Payments to Acquire Held-to-maturity Securities Short-term investments Payments to Acquire Property, Plant, and Equipment Capital expenditures Increase (Decrease) in Restricted Cash Restricted cash Statement [Table] Statement [Line Items] Statement Assets [Abstract] ASSETS Assets, Current [Abstract] Current assets Liabilities and Stockholders' Equity [Abstract] LIABILITIES AND SHAREHOLDERS' EQUITY Liabilities, Current [Abstract] Current liabilities Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Shareholders' equity Statement, Scenario [Axis] Scenario, Unspecified [Domain] Payments to Acquire Businesses, Net of Cash Acquired Acquisition of Terrane, net of cash acquired of $27.1 million (Note 4) Net Cash Provided by (Used in) Investing Activities Cash used in investing activities Proceeds from Issuance of Common Stock Proceeds from issuance of common shares, net Payments for Repurchase of Common Stock Repurchase of common shares Net Cash Provided by (Used in) Financing Activities Cash generated (used) by financing activities Effect of Exchange Rate on Cash and Cash Equivalents EFFECT OF EXCHANGE RATE CHANGES ON CASH Cash and Cash Equivalents, Period Increase (Decrease) INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS Stock Issued During Period Value Stock Warrants Exercised This element represents the value of stock issued during the period as a result of the exercise of stock options. Exercise of warrants Stock Issued During Period Shares Stock Warrants Exercised This element represents the number of shares issued during the period as a result of the exercise of stock options. Exercise of warrants (in shares) Cumulative Adjustment Warrant Accounting Cumulative adjustment-warrant accounting (Note 8d) This element represent Cumulative adjustment warrant accounting. Shares, Issued Balances (in shares) Balances (in shares) Stock Issued During Period, Value, New Issues Issuance of common stock, net Stock Issued During Period, Shares, New Issues Issuance of common stock, net (in shares) Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition, Value Amortization of stock-based compensation Stock Issued During Period, Value, Stock Options Exercised Proceeds from stock option exercises Stock Issued During Period, Shares, Stock Options Exercised Proceeds from stock option exercises (in shares) Adjustments to Additional Paid in Capital, Tax Effect from Share-based Compensation Tax benefit of employee stock option exercises Retained Earnings Retained Earnings [Member] Accumulated Other Comprehensive Income (Loss) Accumulated Other Comprehensive Income [Member] Comprehensive Income Comprehensive Income [Member] CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY and COMPREHENSIVE INCOME Common Stock Purchase Warrants Warrants [Member] Stock Repurchased During Period, Value Share Repurchase Stock Repurchased During Period, Shares Share Repurchase (in shares) Balances Adjusted (in shares) Balance Adjusted, Shares Balances Adjusted (in shares) This element represents the balance in terms of shares adjusted on account of an adjustment made to give effect to pronouncements in relation to warrant accounting. Other Comprehensive Income, Defined Benefit Plans Adjustment, Net of Tax Post retirement benefit, net of tax Nature of Operations [Text Block] Description of Business Inventory Disclosure [Text Block] Inventory Inventory Description of Business Other Comprehensive Income, Foreign Currency Transaction and Translation Adjustment, Net of Tax Foreign currency translation Comprehensive Income, Net of Tax, Including Portion Attributable to Noncontrolling Interest Total comprehensive income Balance Adjusted, Value Balances Adjusted This element represents the balance adjusted on account of an adjustment made to give effect to pronouncements in relation to warrant accounting. Balances Adjusted Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Shareholders' Equity Comprehensive Income, Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract] Comprehensive income: Stockholders' Equity, Period Increase (Decrease) Stock Issued During Period, Shares, Period Increase (Decrease) Statement, Equity Components [Axis] Equity Component [Domain] Common Stock Common Stock [Member] Paid-in Capital Additional Paid-in Capital [Member] Goodwill Goodwill [Text Block] Asset Retirement Obligations Asset Retirement Obligations And Environmental Cost Policy [Text Block] Shareholders' Equity Shareholders' Equity [Text Block] Stock-based Compensation Stock-Based Compensation [Text Block] Exploration Schedule Of Capitalized Costs Of Unproved Properties Excluded From Amortization [Text Block] Employee Benefits Pension and Other Postretirement Benefits Disclosure [Text Block] Subsequent Events Schedule of Subsequent Events [Text Block] Significant Accounting Policies Significant Accounting Policies [Text Block] Significant Accounting Policies Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Text Block] Recent Accounting Pronouncements Recent Accounting Pronouncements Terrane Acquisition Business Combination Disclosure [Text Block] Terrane Acquisition Property, Plant and Equipment Disclosure [Text Block] Property, Plant and Equipment Property, Plant and Equipment Reconciliation to Canadian Generally Accepted Accounting Principles Reconciliation to Canadian Generally Accepted Accounting Principles Reconciliation to Canadian Generally Accepted Accounting Principles [Text Block] This element may be used to capture reconciliation of significant differences between US GAAP and Canadian GAAP and their effect on the consolidated financial statements as a single block of text. Basis of Presentation Document and Entity Information Derivative Financial Instruments Fair Value Measurement Long-term Debt Commitments and Contingencies Income and Mining Taxes Related Party Transactions Supplementary Cash Flow Information Concentration of Credit Risk Segment Information Reclamation Bonds. Reclamation Bonds Reclamation Bonds This element can be used to capture the entire disclosure about reclamation bonds and mine closing liability. Net Income per Share Healthcare Legislation Healthcare Legislation Disclosure [Text Block] Healthcare Legislation This element represents the potential financial impact of the Health Care and Education Reconciliation Act of 2010, which is a reconciliation bill that amends the Patient Protection and Affordable Care Act, on the consolidated financial statements of the company. Goodwill Asset Retirement Obligations Shareholders' Equity Stock-based Compensation Exploration Employee Benefits Subsequent Events Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Basis of Presentation Derivative Financial Instruments Derivative Instruments and Hedging Activities Disclosure [Text Block] Fair Value Measurement Fair Value, Measurement Inputs, Disclosure [Text Block] Long-term Debt Long-term Debt [Text Block] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Income and Mining Taxes Income Tax Disclosure [Text Block] Related Party Transactions Related Party Transactions Disclosure [Text Block] Supplementary Cash Flow Information Cash Flow, Supplemental Disclosures [Text Block] Concentration of Credit Risk Concentration Risk Disclosure [Text Block] Segment Information Segment Reporting Disclosure [Text Block] Net Income per Share Earnings Per Share [Text Block] Summary of Quarterly Financial Data (Unaudited) Quarterly Financial Information [Text Block] Summary of Quarterly Financial Data (Unaudited) Gold Stream Arrangement Gold Stream Arrangement Gold Stream Arrangement [Text Block] This element represents details of the purchase and sale agreement for the sale of payable gold related to the Company's Mt. Milligan project, deposits received along with terms of adjustments of the purchase price and also the accounting treatment. Proceeds from Deposits Received Under Arrangement This element represents proceeds from deposits received under the purchase and sale agreement entered related to the future sale of payable gold related to the Company's Mt. Milligan property. Proceeds from the sale of Gold Stream Adjustments to Additional Paid Stock Issued Exercise of Options Transferred from paid-in capital on exercise of options This element represents the adjustment made to additional paid-in capital resulting from options exercised during the reporting period. Asset retirement obligations Asset Retirement Obligations, Noncurrent Interest and finance fees Interest Expense Amortization of finance fees Amortization of Financing Costs and Discounts Deposits CONSOLIDATED STATEMENTS OF OPERATIONS Acquisition costs Acquisition Costs Cost of Revenue [Abstract] Costs of sales Cost of Revenue Total costs of sales Gold Stream Arrangement, Noncurrent Gold Stream arrangement (Note 11) Represents outstanding amount of deposit received related to a purchase and sale agreement for the future sale of payable gold related to the Company's Mt. Milligan property. Cash Acquired from Acquisition Acquisition of Terrane, cash acquired