Entity [Domain] Document and Entity Information [Abstract] Document and Entity Information [Abstract] Statements [Table] Statement [Table] Legal Entity [Axis] Statements [Line Items] Statement [Line Items] Document Type Amendment Flag Amendment Description Document Period End Date Trading Symbol Entity Registrant Name Entity Central Index Key Current Fiscal Year End Date Entity Emerging Growth Company Entity Filer Category Entity Common Stock, Shares Outstanding Entity Current Reporting Status Entity Voluntary Filers Entity Well Known Seasoned Issuer Entity Public Float Document Fiscal Year Focus Document Fiscal Period Focus Income Statement Revenue Revenue Revenue recognized Cost Of Sales [Abstract] Cost of sales Cost of sales: Cost of sales Production Cost Total Production costs Production costs Production costs Total production costs Total production costs Production costs Depreciation and amortisation expense Depreciation and depletion expense Depreciation and depletion Depreciation and depletion Royalties Royalties Royalties Total cost of sales Total cost of sales Total cost of sales Total cost of sales Income from mine operations Income from mine operations Income from mine operations Income (loss) from mine operations Share of profit (loss) of joint ventures accounted for using equity method Share of net loss related to joint venture Company's share of net loss of joint venture Service Fee Income Net Earned As Operators Of Joint Venture Service fee earned as operators of joint venture Service fee earned as operators of joint venture Represent the amount of net service fees and income earned as operators of Joint venture. Exploration and evaluation expenditures Exploration and evaluation expenditures Exploration and evaluation expenditures General and administrative expenses Total General and administrative expenses General and administrative expenses Total Income from operations Income (loss) from operations Income from operations and joint venture Gains (losses) recognised when control of subsidiary is lost Loss due to loss of control of subsidiaries Loss associated with loss of control of former Ghanaian subsidiaries Loss associated with loss of control of former Ghanaian subsidiaries Finance expense Total Finance expense Finance expense Total Finance income Finance income Foreign exchange gain (loss) Foreign exchange (loss) gain Foreign exchange loss Loss before taxes Income (loss) before income taxes Income (loss) before income taxes Income (loss) before income taxes Current income tax expense Current tax expense Current income tax expense Current income tax expense Current income tax expense Deferred income tax expense (DeferredTaxExpenseIncome) Deferred tax expense Deferred income tax recovery (expense) Deferred income tax expense Deferred income tax expense Net income (loss) and comprehensive income (loss) for the year Net income and comprehensive income for the period Net income (loss) and comprehensive income (loss) for the period Net income (loss) and comprehensive income (loss) for the year Net income (loss) attributable to: Common shareholders of the Company Common shareholders of the Company Net income (loss) attributable to common shareholders Non-controlling interest (ProfitLossAttributableToNoncontrollingInterests) Non-controlling interest Net earnings attributable to non-controlling interest Net loss of the JV for the period Net (loss) income for the year Net income (loss) for the year Earnings (loss) per share attributable to common shareholders: Basic (in dollars per share) Diluted (in dollars per share) Weighted average number of shares outstanding: Basic (WeightedAverageShares) Basic (in shares) Weighted average number of ordinary shares - basic Diluted (AdjustedWeightedAverageShares) Diluted (in shares) Weighted average number of ordinary shares - diluted Statement of Financial Position Assets Current assets Cash and cash equivalents Cash and cash equivalents Cash and cash equivalents, beginning of year Cash and cash equivalents, end of year Receivables Current receivables due from related parties Receivable due from related party Inventories Total current inventories Prepaid expenses and deposits Prepaid expenses and deposits VAT receivable VAT receivable VAT receivable Total current assets Current assets Total current assets Non-current assets Inventories (NoncurrentInventories) Inventories Reclamation deposit Reclamation deposit Reclamation deposit Preferred Shares Non Current Preferred shares The amount of preferred shares held by the entity. Exploration and evaluation assets Exploration and evaluation assets Mineral properties, plant and equipment Mineral properties, plant and equipment Investments in joint ventures Interest in Joint Venture Balance, January 1, 2018 Balance, December 31, 2018 Total equity investment including cash investment Total non-current assets Total non-current assets Total assets Total assets Total assets Liabilities Current liabilities Accounts payable and accrued liabilities Accounts payable and accrued liabilities Accounts payable and accrued liabilities Accounts payable and accrued liabilities Foreign currency forward contract liability Current portion of long-term debt Current portion of long-term debt Total current liabilities Current liabilities Total current liabilities Non-current liabilities Long-term debt Long-term debt Non-current portion of debt Long Term Incentive Plan Cash Settled Long-term incentive plan (cash-settled awards) Long-term incentive plan liability Amount of long-term incentive plan cash settled. Asset retirement provisions Asset retirement provisions Balance, beginning of year Balance, end of year Estimated present value of obligation Asset retirement provisions Deferred income tax liability Net deferred tax liabilities Total non-current liabilities Non-current liabilities Total non-current liabilities Total liabilities Total liabilities Total liabilities Equity and liabilities [abstract] Equity Equity Abstract Common shareholders' equity Share capital Equity reserves Accumulated deficit Accumulated deficit Total common shareholders' equity Total common shareholders' equity Total common shareholders' equity Non-controlling interest Non-controlling interest Non-controlling interest, beginning balance Non-controlling interest, ending balance Non-controlling interest Equity Total equity Beginning Balance Ending Balance Total liabilities and equity Total liabilities and equity Statement Of Changes In Equity [Abstract] Components of equity [Axis] Equity components [Domain] Share capital [Member] Equity reserves [Member] Accumulated deficit [Member] Non-controlling interest [Member] Beginning Balance (shares) Beginning Balance (shares) Ending Balance (shares) Issuance Of Common Shares For [Abstract] Issuance of common shares for: Exercise of share-based options Issued pursuant to exercise of share-based options (note 19(a)) Increase Decrease Through Exercise Of Options Shares Issued pursuant to exercise of share-based options (note 19(a)) (shares) Exercise of share-based options (shares) Exercise of share-based options (shares) Shares Issued During Period Value For Private Placement Net Of Share Issuance Cost Issued pursuant to private placement, net of share issuance cost Private placement, net of share issuance costs Amount of share issued pursuant to private placement, net of share issuance cost. Shares Issued During Period Shares For Private Placement Net Of Share Issuance Cost Number of common shares issued for private placement Issued pursuant to private placement, net of share issuance cost (shares) Private placement, net of share issuance costs (shares) Number of shares issued to to private placement, net of share issuance cost. Shares Issued During Period Value For Bought Deal Financing Bought deal financing Bought deal financing Shares Issued During Period Shares For Bought Deal Financing Issued pursuant to bought deal financing (shares) Bought deal financing (shares) Bought deal financing (shares) Shares Issued During Period Value Asset Acquisition Issued pursuant to asset acquisition Asset acquisition Asset acquisition Shares Issued During Period Shares Asset Acquisition Issued pursuant to asset acquisition (shares) Asset acquisition (shares) Asset acquisition (shares) Share Based Payments Share-based payments Share-based payments Share-based payments Share Purchase Warrants Share-purchase warrants Share-purchase warrants Derecognition Of Non-Controlling Interest On Loss Of Control Derecognition of non-controlling interest on loss of control Derecognition of non-controlling interest on loss of control Statement of Cash Flows Operating activities: Adjustments for: Depreciation and depletion (AdjustmentsForDepreciationAndAmortisationExpense) Depreciation and depletion Adjustments for gain (loss) on disposal of investments in subsidiaries, joint ventures and associates Loss due to loss of control of subsidiaries Loss due to loss of control of subsidiaries Adjustments For Share Of Net Loss Related To Joint Venture Share of net loss related to joint venture Adjustments for gains (losses) on Share of net loss related to joint venture. Finance expense (AdjustmentsForFinanceCosts) Finance expense Interest and other income Interest and other income Deferred income tax expense Share-based payments Unrealized foreign exchange loss (gain) Operating cash flow before working capital changes Change in non-cash working capital Operating cash flow before working capital changes Change in non-cash working capital Cash provided by operating activities Net cash provided by operating activities after working capital changes Cash provided by operating activities Investing activities: Expenditures on mineral properties, plant and equipment Expenditures on mineral properties, plant and equipment Other cash payments to acquire interests in joint ventures, classified as investing activities Gold Fields investment in joint venture Gold Fields investment in joint venture Joint Venture Transaction Costs Paid Classified As Investing Activities Joint venture transaction costs paid The cash outflow for the Joint venture transaction costs paid. Joint venture transaction costs paid Cash And Cash Equivalents Derecognized On Loss Of Control Classified As Investing Activities Cash and cash equivalents derecognized on loss of control Represents cash and cash equivalents derecognized on loss of control classified as investing activities. Interest received Cash provided by (used for) investing activities Net cash used in investing activities Cash provided by (used in) in investing activities Financing activities: Shares issued for cash, net of share issuance costs Gross proceeds of weighted average price Repayments of non-current borrowings Repayment of long-term debt Repayment of long-term debt Interest and associated withholding tax paid Interest and associated withholding tax paid Interest and associated withholding tax paid Cash provided by (used for) financing activities Net cash provided by (used in) financing activities Cash used in financing activities Impact of foreign exchange on cash and cash equivalents Increase (decrease) in cash and cash equivalents for the year Change in cash and cash equivalents during the year Notes to Financial Statements [Abstract] Notes to Financial Statements [Abstract] Disclosure Of Nature Of Operations Explanatory Nature of operations [Text Block] Nature of operations [Text Block] Basis of presentation [Text Block] Significant accounting policies [Text Block] Changes in accounting standards [Text Block] Significant accounting judgements and estimates [Text Block] Joint Venture Transaction [Abstract] Disclosure of joint ventures [text block] Joint venture transaction [text block] Revenue [Text Block] Production costs by nature [Text Block] General and administrative expenses [Text Block] Finance expense [Text Block] Income tax [Text Block] Non-controlling interest [Text Block] Earnings (loss) per share attributable to common shareholders [Text Block] Disclosure of financial assets [abstract] Disclosure of financial assets [text block] Financial assets [text block] Inventories [Text Block] Disclosure of summary of inventories held by the AGM of joint venture Disclosure Of Mineral Properties Plant And Equipment And Exploration And Evaluation Assets Explanatory [Text Block] Mineral properties, plant and equipment and exploration and evaluation assets [Text Block] Mineral properties, plant and equipment and exploration and evaluation assets [Text Block] Long-term debt [Text Block] Disclosure Of Asset Retirement Obligation Explanatory Asset retirement obligation [Text Block] Asset retirement obligation [Text Block] Share capital [Text Block] Equity reserves [Text Block] Disclosure of commitments and contingent liabilities [text block] Commitments and contingencies [text block] Supplemental cash flow information [Text Block] Disclosure of cash flows Investment In Joint Venture [Abstract] Investment In Joint Venture [Text Block] Represents Joint venture transaction. Segmented information [Text Block] Capital management [Text Block] Financial instruments [Text Block] Related party transactions [Text Block] Business combinations [Policy Text Block] Description of accounting policy for investments in joint ventures [text block] Investments in joint arrangements [text block] Non-controlling interest [Policy Text Block] Foreign currency translation [Policy Text Block] Cash and cash equivalents [Policy Text Block] Inventories [Policy Text Block] Mineral properties, plant and equipment [Policy Text Block] Provisions [Policy Text Block] Revenue from contracts with customers [Text Block] Description Of Accounting Policy For Royalties And Mining Taxes Policy [Text Block] Royalties and mining taxes [Policy Text Block] Description of Accounting Policy for Royalties and mining taxes Financial instruments [Policy Text Block] Share-based compensation [Policy Text Block] Income taxes [Policy Text Block] Income (loss) per share [Policy Text Block] Subsidiaries [Axis] Subsidiaries [Domain] Asanko Gold Mine [Member] Asanko Gold Mine (AGM) [Member] Thie member stands for Asanko Gold Mine. Disclosure Of Investment In Joint Venture [Table Text Block] Disclosure of Investment in Joint Venture using equity method Entire disclosure of about investment in the joint venture. Disclosure of reconciliation of summarised financial information of joint venture accounted for using equity method to carrying amount of interest in joint venture [text block] Disclosure of statement of operations of Joint Venture Disclosure Of Production Costs [Table Text Block] Disclosure of production costs of joint venture The entire disclosure about production costs. Disclosure Of Fair Value Adjustment Associated With Joint Venture Explanatory [Table Text Block] Disclosure of after-tax amount recognized in records of AGM of joint venture Disclosure of fair value adjustment associated with joint venture. Disclosure Of Movement In The Asset Retirement Obligation [Table Text Block] Disclosure of movement in the asset retirement obligation of the AGM of joint venture Entire disclosure about movement in the asset retirement obligation .