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Arbutus Inc. Arbutus Inc. [Member] Arbutus Inc. [Member] Other Liabilities Disclosure [Abstract] Other Liabilities Disclosure [Abstract] All Trading Arrangements All Trading Arrangements [Member] All Adjustments to Compensation All Adjustments to Compensation [Member] Award Timing Disclosures [Line Items] Blumberg and Drexel Blumberg and Drexel [Member] Blumberg and Drexel [Member] Title of Individual [Domain] Title of Individual [Domain] Compensation Amount Outstanding Recovery Compensation Amount Additional paid-in capital Additional Paid in Capital Research and Development Arrangement, Contract to Perform for Others, Type [Axis] Research and Development Arrangement, Contract to Perform for Others, Type [Axis] Restricted stock units forfeited, canceled or expired (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Research and Development Arrangement, Contract to Perform for Others [Line Items] Research and Development Arrangement, Contract to Perform for Others [Line Items] Issuance of common shares pursuant to exercise of stock options Proceeds from Stock Options Exercised Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table] Share-Based Payment Arrangement, Option, Exercise Price Range [Table] Barinthus Barinthus [Member] Barinthus Issuance of common shares pursuant to the Open Market Sales Agreement (in shares) Stock Issued During Period, Shares, New Issues, Open Market Sale Agreement Stock Issued During Period, Shares, New Issues, Open Market Sale Agreement Share-Based Payment Arrangement, Tranche Three Share-Based Payment Arrangement, Tranche Three [Member] Deferred income taxes Income Tax, Policy [Policy Text Block] Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Document Financial Statement Error Correction [Flag] Document Financial Statement Error Correction [Flag] Restricted stock units forfeited, canceled or expired (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Investment in Genevant Equity Method Investments [Policy Text Block] October 2021 Prospectus Supplement October 2021 Prospectus Supplement [Member] October 2021 Prospectus Supplement Qilu Pharmaceutical Co, LTD. 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