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Note 9 - Accrued Liabilities Non-current liabilities: Note 10 - Shareholders' Equity Advances to vendor The amount of advances to vendor held as an asset by the company. Note 11 - Net Loss Per Share Non-cash lease expense Amount of expense recognized over the period for lease expense, non-cash. Note 13 - Share-based Compensation Deferred Share Units [Member] Related to deferred share units. Change in fair value of warrant liability dmac_UnitsNumberOfCommonSharePurchaseWarrantPerUnit Units, Number of Common Share Purchase Warrant Per Unit The number of common share purchase warrant per unit. Unrealized gain on marketable securities Note 4 - Marketable Securities - Fair Value of Marketable Securities (Details) dmac_UnitsNumberOfCommonSharesPerUnit Units, Number of Common Shares Per Unit The number of common shares per unit. 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Note 11 - Net Loss Per Share - Schedule of Antidilutive Shares Excluded from Computation of Net Loss Per Share (Details) Commercial Paper and Corporate Bonds [Member] Commercial Papers are unsecured promissory note (generally negotiable) that provides institutions with short-term funds that is excluded from cash and cash equivalents and commercial bonds are debt securities issued by domestic or foreign corporate business, banks and other entities with a promise of repayment. Note 13 - Share-based Compensation - Share-based Compensation Expense (Details) Note 13 - Share-based Compensation - Stock Option Activity (Details) Compensation Warrants [Member] Related to compensation warrants. dmac_CollaborationAgreementPercentOfRoyaltiesUponDevelopmentAndSalesMilestones Collaboration Agreement, Percent of Royalties Upon Development and Sales Milestones The percent of royalties upon development and sales milestones in a collaboration agreement. Note 13 - Share-based Compensation - Stock Options Outstanding (Details) dmac_WarrantsAndRightsOutstandingExpirationStockPriceTrigger Warrants and Rights Outstanding, Expiration, Stock Price Trigger The expiration stock price trigger of warrants and rights outstanding. Notes To Financial Statements Ahon Pharma [Member] Related to Ahon Pharma. Notes To Financial Statements [Abstract] DiaMedica [Member] Related to DiamMedica. Fair Value, Marketable Securities Measured on a Recurring Basis [Table Text Block] Tabular disclosure of marketable securities measured at fair value that are classified in stockholders' equity, if any, by class that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). SK Group [Member] Related to the SK Group. Stock Options Outstanding [Member] Related to stock options outstanding. Common Stock Reserved for Future Issuance [Table Text Block] A tabular disclosure of common stock reserved for future issuance. Share-based Payment Arrangement, Option, Activity [Table Text Block] dmac_SharebasedCompensationArrangementBySharebasedPaymentAwardMaximumNumberOfShares Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares The highest number of shares that can be issued under the plan. The 2012 DSU Plan [Member] Related to the 2012 DSU plan. DiaMedica Stock Option Plan [Member] Related to the DiaMedia stock option plan. Exercise Price Range 1 [Member] Related to the first exercise price range. The 2012 DSU Plan and Option Plan [Member] Related to both the 2012 DSU plan and Option plan. Option Plan [Member] Related to the Option Plan. Exercise Price Range 5 [Member] Related to the fifth exercise price range. Depreciation Exercise Price Range 4 [Member] Related to the fourth exercise price range. US Government Agencies Debt Securities [Member] Exercise Price Range 3 [Member] Related to the third exercise price range. Exercise Price Range 2 [Member] Related to the second exercise price range. 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Balance, aggregate intrinsic value Sales-based taxes receivable us-gaap_PaymentsToAcquireMarketableSecurities Purchase of marketable securities Common shares, no par value; unlimited authorized; 11,956,874 shares issued and outstanding, as of March 31, 2019 and December 31, 2018, respectively Financial Instruments [Domain] Adjustments to reconcile net loss to net cash used in operating activities: Measurement Frequency [Axis] Balance, weighted average exercise price (in CAD per share) Measurement Frequency [Domain] Fair Value, Recurring [Member] Common shares, authorized Forfeited, weighted average exercise price (in CAD per share) Common shares, issued (in shares) Expired / cancelled, weighted average exercise price (in CAD per share) us-gaap_LesseeOperatingLeaseDiscountRate Lessee, Operating Lease, Discount Rate Financial Instrument [Axis] Common shares, par value (in dollars per share) Common Stock, No Par Value Granted, weighted average exercise price (in CAD per share) Exercised, weighted average exercise price (in CAD per share) Accrued liabilities Total accrued liabilities Accrued compensation Common stock reserved for future issuance (in shares) Common Stock, Capital Shares Reserved for Future Issuance Lessee, Operating Leases [Text Block] Accounts payable dmac_ClassOfWarrantOrRightIssuedDuringPeriod Class of Warrant or Right, Issued During Period The number of warrants or rights issued during period. 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Additional Paid-in Capital [Member] Related Party Transactions Disclosure [Text Block] us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments Loss before income tax expense Income tax expense us-gaap_IncreaseDecreaseInAccruedLiabilities Accrued liabilities Equity Components [Axis] Equity Component [Domain] us-gaap_IncreaseDecreaseInAccountsPayable Accounts payable us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 Class of Warrant or Right, Exercise Price of Warrants or Rights Class of Warrant or Right [Axis] Class of Warrant or Right [Domain] us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight Class of Warrant or Right, Number of Securities Called by Each Warrant or Right us-gaap_OperatingExpenses Total operating expense General and administrative Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value, Ending Balance Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Total share-based compensation Computer Equipment [Member] Cash and Cash Equivalents, Policy [Policy Text Block] Amendment Flag General and Administrative Expense [Member] Accounting Policies [Abstract] Significant Accounting Policies [Text Block] us-gaap_ComprehensiveIncomeNetOfTax Net loss and comprehensive loss Basis of Accounting, Policy [Policy Text Block] New Accounting Pronouncements, Policy [Policy Text Block] Common shares, outstanding (in shares) Current Fiscal Year End Date us-gaap_VariableLeaseCost Variable Lease, Cost Research and Development Expense [Member] Document Fiscal Period Focus us-gaap_OperatingLeaseCost Operating Lease, Cost Document Fiscal Year Focus Document Period End Date Income Statement Location [Axis] us-gaap_IncreaseDecreaseInPrepaidExpense Prepaid expenses Income Statement Location [Domain] Entity Ex Transition Period Entity Emerging Growth Company Document Type Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Entity Small Business Document Information [Line Items] Document Information [Table] Entity Filer Category Entity Current Reporting Status Weighted average shares outstanding – basic and diluted (in shares) Weighted average shares outstanding—basic and diluted (in shares) Employee and non-employee stock options (in shares) us-gaap_IncreaseDecreaseInAccountsReceivable Amounts receivable Basic and diluted net loss per share (in dollars per share) Basic and diluted net loss per share (in dollars per share) Entity Central Index Key Entity Registrant Name Entity [Domain] Legal Entity [Axis] Statement [Table] us-gaap_MinorityInterestOwnershipPercentageByParent Noncontrolling Interest, Ownership Percentage by Parent Statement of Financial Position [Abstract] Issuance of common stock and warrants, offering costs Accounts Payable and Accrued Liabilities Disclosure [Text Block] Statement of Cash Flows [Abstract] Entity Common Stock, Shares Outstanding (in shares) Statement of Stockholders' Equity [Abstract] Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Income Statement [Abstract] Schedule of Accrued Liabilities [Table Text Block] Trading Symbol us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised Exercised (in shares) us-gaap_TableTextBlock Notes Tables Related Party [Axis] Related Party [Domain] us-gaap_LiabilitiesNoncurrent Total non-current liabilities Granted (in shares) Cash flows from financing activities: us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod Forfeited (in shares) us-gaap_WarrantsAndRightsOutstandingTerm Warrants and Rights Outstanding, Term Share-based compensation us-gaap_LiabilitiesAndStockholdersEquity Total liabilities and shareholders’ equity Related Party Transaction [Axis] Related Party Transaction [Domain] Accumulated deficit Retained Earnings (Accumulated Deficit), Ending Balance Research and development 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Includes allocation of proceeds of debt securities issued with detachable stock purchase warrants. dmac_IncomeFromGovernmentalAssistance Governmental assistance - research incentives The amount of income generated from governmental assistance including, but not limited to, research incentives and grants. Operating lease obligation Outstanding, weighted average exercise price (in CAD per share) Finance lease obligation dmac_StockIssuedDuringPeriodSharesExerciseOfCommonStockWarrants Stock Issued During Period, Shares, Exercise of Common Stock Warrants The number of shares issued during the period due to the exercise of common stock warrants. Outstanding, weighted average remaining contractual life (Year) Exercisable, shares (in shares) Finance lease obligation, non-current Deposit Total deposit Issuance of common stock and warrants, net offering costs of $529 Value of common stock and warrants for issued. Per share exercise price, upper range (in CAD per share) Operating lease right-of-use asset Total lease payments Proceeds from issuance of common shares and warrants, net of offering costs Amount of cash inflow from the issuance of common stock and warrants. us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount Less interest portion us-gaap_FinanceLeasePrincipalPayments Principal payments on finance lease obligations Outstanding, shares (in shares) 2021 Exercise Price Range [Axis] dmac_UnitsIssuedDuringPeriodUnitsNewIssues Units Issued During Period, Units, New Issues Number of new units issued during the period. 2022 Exercise Price Range [Domain] dmac_WorkingCapital Working Capital The amount of working capital. Risks and Uncertainties [Text Block] A complete disclosure of the risks and uncertainties the company may face. Per share exercise price, lower range (in CAD per share)