Segment reporting Disclosure of geographical areas [line items] Ifrs Type of Arrangement and Non-arrangement Transactions [Axis] Ifrs Type of Arrangement and Non-arrangement Transactions [Axis] Information by category of arrangement, including but not limited to collaborative arrangements and non-collaborative arrangements. Purchase of property, plant and equipment Purchase of property, plant and equipment, classified as investing activities Short‑term employee benefits - Salaries Wages and salaries Entity File Number Entity File Number Schedule of trade and other receivables Disclosure of Detailed Information About Trade And Other Receivables [Table Text Block] Tabular disclosure of trade and other receivables. Schedule of intangible assets Disclosure of detailed information about intangible assets [text block] Levels of fair value hierarchy [domain] Levels of fair value hierarchy [domain] Restricted assets - non-current Noncurrent Restricted Assets [Member] This member stands for Noncurrent restricted cash. Nominated targets under agreement Number on Nominated Target Under Agreement Number on Nominated Target Under Agreement Recognized in equity Deferred Tax Income Recognized In Equity The amount of tax income relating to changes in deferred tax assets, recognized in Equity. Cost of restricted stock units granted in the year for the Senior Management Team Restricted Stock Units Granted, Value The amount of restricted stock units granted in a year. Preferred class C shares Preferred Class C Shares [Member] This member stands for preferred class C shares. Preferred class D shares Preferred Class D Shares [Member] Preferred Class D Shares Cash and cash equivalents [abstract] Net cash flows from/(used) in operating activities, before interest and taxes Cash flows from (used in) operations Other Other tax effects for reconciliation between accounting profit and tax expense (income) Fair value (loss)/gain on investments in equity instruments designated as FVTOCI Other comprehensive income, net of tax, gains (losses) from investments in equity instruments Schedule of financial position relating to leases Disclosure of quantitative information about right-of-use assets [text block] Ranges of exercise prices for outstanding share options [axis] Ranges of exercise prices for outstanding share options [axis] Purchase of current financial assets Purchase of financial instruments, classified as investing activities Research and development incentive receivables - non-current Research and development incentive receivables - non-current member [Member] Represents the information pertaining to non current research and development incentive receivables. Vesting of RSUs (in shares) Number of RSUs - Vested (in shares) Number of PSUs - Vested (in shares) Number of other equity instruments exercised or vested in share-based payment arrangement Cost at beginning Cost at ending Non-current financial assets at fair value through profit or loss 718.16 718.16 [Member] 718.16 Statement of comprehensive income [abstract] Statement of changes in equity [line items] Statement of changes in equity [line items] Total comprehensive profit/(loss) attributable to: Comprehensive income attributable to [abstract] 489.27 489.27 [Member] 489.27 Collaborative arrangement maximum commercial milestone payments to be received on exercise of option Collaborative arrangement maximum commercial Milestone payments to be received on exercise of Option The maximum amount of payment to be received for commercial milestone on exercise of option. Disclosure of geographical areas [table] Disclosure of geographical areas [table] argenx Spain S.L. - Sucursal em Portugal argenx Spain S.L. - Sucursal em Portugal [Member] argenx Spain S.L. - Sucursal em Portugal FVTPL Financial assets at fair value through profit or loss, category [member] Statement of financial position [abstract] Other operating income Other operating income (expense) Cover [Abstract] Maximum Maximum [Member] 304.91 304.91 [Member] 304.91 Schedule of current prepaid expenses Schedule of Prepaid Expenses [Table Text Block] The tabular disclosure of prepaid expenses, current. Schedule of average number of full-time equivalents by function Disclosure of Full Time Equivalents Employees [Table Text Block] The tabular disclosure of full-time equivalents employees. argenx Austria Services GmbH argenx Austria Services GmbH [Member] argenx Austria Services GmbH Classes of intangible assets other than goodwill [axis] Classes of intangible assets other than goodwill [axis] argenx Switzerland, S.A. Argenx Switzerland, S.A. [Member] Argenx Switzerland, SA. Non-current financial assets held at fair value through profit or loss Non-current financial assets at fair value through profit or loss, classified as held for trading Schedule of roll forward of number of shares outstanding Reconciliation of number of shares outstanding [Table Text Block] Tabular disclosure of issued capital. Entity Shell Company Entity Shell Company Share premium Share premium argenx Australia Pty. Ltd. Argenx Australia Pty. Ltd [Member] Argenx Australia Pty. Ltd argenx US, Inc. ARGENX US INC [Member] This member stands for ARGENX US INC. Disclosure of reconciliation of changes in property, plant and equipment, including right-of-use assets [table] Disclosure of reconciliation of changes in property, plant and equipment, including right-of-use assets [table] AgomAb Therapeutics NV AgomAb Therapeutics NV [Member] AgomAb Therapeutics. Basis of consolidation Description of Accounting Policy for Basis of Consolidation [Policy Text Block] The description of accounting policy for basis of consolidation. Inventories in process Current work in progress Ordinary shares withheld for payment of employees’ withholding tax liability Decrease Increase Through Shares Withheld for Employee Tax Holding Liability Ordinary shares withheld for payment of employees' withholding tax liability. Number of members Number Of Members Number Of Members Document Fiscal Period Focus Document Fiscal Period Focus 430.17 - 699.60 Exercise Price 430.17 - 699.60 [Member] Exercise Price 430.17 - 699.60 Total assets Assets Income taxes Description of accounting policy for income tax [text block] Exchange gains/(losses) Gains (losses) on exchange differences on translation of foreign operations, before tax Number of RSUs - January 1 (in shares) Number of RSUs - December 31 (in shares) Number of other equity instruments outstanding in share-based payment arrangement General Information about the Company Disclosure of general information about the company [text block] The entire disclosure for general information about the company. Current tax expense Current tax expense (income) and adjustments for current tax of prior periods Trading Symbol Trading Symbol Auditor's Remuneration [Line Items] Auditor's Remuneration [Line Items] Auditor's Remuneration 299.74 299.74 [Member] 299.74 Entity Address, City or Town Entity Address, City or Town Share capital Issued capital [member] Ifrs Grantee Status [Axis] Ifrs Grantee Status [Axis] Information by status of recipient to whom award is granted. 2033 2033 [Member] This member stands for Expiry date 2033. Schedule of remuneration package of members of key management personnel Disclosure of information about key management personnel [text block] Equity attributable to owners of the parent Equity Attributable To Owners Of Parent [Abstract] Equity Attributable To Owners Of Parent Disclosure of quantitative information about right-of-use assets [table] Disclosure of quantitative information about right-of-use assets [table] Entity Emerging Growth Company Entity Emerging Growth Company Collaborative arrangements amount of preclinical milestones payment received Collaborative Arrangements Amount of Preclinical Milestones Payment Received The amount of preclinical milestones payments received in collaborative arrangements. Trade and other payables Description of accounting policy for trade and other payables [text block] Research and development incentives receivables Description of Accounting Policy for Research and Development Incentive Receivables [Policy Text Block] The description of accounting policy for research and development incentive receivables. Termination benefits Termination benefits expense Income tax (expense)/benefit calculated at the Dutch statutory federal income tax rates Tax expense (income) at applicable tax rate Commitments [Table] Commitments [Table] Disclosure of information about obligations resulting from commitments. Exercise price per stock options (in USD per share) Exercise price (in USD per share) Exercise price of outstanding share options Prepaid expenses Total prepaid expenses Current prepaid expenses Employer social security Key Management Personnel Compensation, Employer Social Security The amount of compensation to key management personnel in the form of employer social security benefits. Assets Assets [abstract] 2029 2029 [Member] This member stands for Expiry date 2029. Foreign exchange gain (loss) [abstract] Non-current financial assets held at fair value through OCI Non-current investments in equity instruments designated at fair value through other comprehensive income Transfer into level 3 liabilities Transfers into Level 3 of fair value hierarchy, liabilities Right-of-use assets Right-of-use assets [member] 350.97 350.97 [Member] 350.97 Rebates and chargebacks Rebates And Charge Backs [Member] This member stands for Rebates and Chargebacks. Share price (in USD per share) Weighted average share price, share options granted (Increase)/decrease in other non‑current assets Adjustments for Decrease (Increase) in Other Non Current Assets Adjustments for decrease (increase) in other non current assets to reconcile profit (loss) to net cash flow from (used in) operating activities. Current assets Current assets [abstract] Other Other current payables Entity Address, Postal Zip Code Entity Address, Postal Zip Code Non‑current assets Non-current assets [abstract] Additions Additions other than through business combinations, property, plant and equipment including right-of-use assets Income taxes Disclosure of income tax [text block] argenx SE ARGENX SE [Member] This member stands for Argenx SE. Facilities and occupancy expenses Facilities And Occupancy Expenses Facilities And Occupancy Expenses Product net sales Description of accounting policy for recognition of revenue [text block] Digital technology expenses Digital Technology Expenses Classified as Selling General and Administrative Expenses Amount of expenses incurred related to information technology. Schedule of non-current financial assets at fair value through profit or loss Non Current Financial Assets at Fair Value Through Profit or Loss [Table Text Block] Tabular disclosure . Issue costs paid Payments for share issue costs Acquired In-Process R&D Acquired In Process Research And Development [Member] Acquired In Process Research And Development Recognition of deferred tax assets Deferred Tax Expense (Income) Relating To Recognition Of Deferred Tax Assets Deferred Tax Expense (Income) Relating To Recognition Of Deferred Tax Assets Schedule of stock options activity Disclosure of number and weighted average exercise prices of share options [text block] 699.60 699.60 [Member] 699.60 Capital commitments [abstract] Software & databases Computer software [member] Digital technology expenses Digital Technology Expenses Classified as Research and Development Digital Technology Expenses Classified as Research and Development Schedule of personnel expenses Disclosure Of Personnel Expenses [Table Text Block] The tabular disclosure of personnel expenses. Cost of Sales Description Of Accounting Policy For Cost Of Sales [Policy Text Block] Disclosure of accounting policy for cost of product sold and service rendered. Share-based payment and income tax deduction on share-based payments Reserve of share-based payments [member] 2024 2024 [Member] This member stands for Expiry date 2024. 563.18 - 837.78 Exercise Price 563.18 - 837.78 [Member] Exercise Price 563.18 - 837.78 Risk-free interest rate (as percent) Risk free interest rate, share options granted Prepaid inventory Prepaid Inventory, Current The amount of prepaid inventory, current. Cash and cash equivalents Description of accounting policy for determining components of cash and cash equivalents [text block] Depreciation and amortization Depreciation And Amortization Expense Selling General and Administrative Expenses Represents depreciation and amortization of assets used in Selling, general and administrative expenses. Reconciliation of number of shares outstanding [abstract] Reconciliation of number of shares outstanding [abstract] Share-based payment Increase (decrease) through share-based payment transactions, equity Recognized in profit or loss Deferred Tax Expense (Income) Recognized In Profit Or Loss In Related To Deferred Tax Laibilities The amount of tax income relating to changes in deferred tax liabilities, recognised in profit or loss. Lease liabilities Lease liabilities [abstract] Currency translation differences, arisen from translating foreign activities Other comprehensive income, net of tax, exchange differences on translation of foreign operations Total non‑current assets Non-current assets External research and development expenses External Research and Development Expenses The amount of expenditure directly attributable to external research or development activities, recognized in profit or loss. 363.31 363.31 [Member] 363.31 Transaction costs for equity issue Share issue related cost Classes of property, plant and equipment [axis] Classes of property, plant and equipment [axis] 4.64 4.64 [Member] This member stands for Exercise price 4.64 Classes of property, plant and equipment [domain] Classes of property, plant and equipment [domain] Entity Address, Country Entity Address, Country Reconciliation of changes in intangible assets other than goodwill [abstract] Reconciliation of changes in intangible assets other than goodwill [abstract] Recognized in profit or loss Deferred Tax Income Recognized in Profit or Loss The amount of tax income relating to changes in deferred tax assets, recognized in profit or loss. 21.63 - 24.87 Exercise Price 21.63 - 24.87 [Member] Exercise Price 21.63 - 24.87 EUR Euro Member Countries, Euro Research and development incentive receivables Research and Development Incentive Receivables, Non Current The amount of research and development incentive receivables including tax incentives classified as non current. (Increase)/decrease in current prepaid expenses Adjustments for Decrease (Increase) in Current Prepaid Expenses Adjustments for Decrease (Increase) in Current Prepaid Expenses Exchange gains/(losses) on cash and cash equivalents Effect of exchange rate changes on cash and cash equivalents Interest received Interest received, classified as investing activities Other Non-Current Assets Disclosure Of Non-Current Financial Assets [Text Block] The disclosure of non-current financial assets. Schedule of stock option arrangement Disclosure of detailed information of share-based payment arrangement [table text block] The disclosure of share based payment arrangements in existence. Foreign currency transactions Description of accounting policy for foreign currency translation [text block] Document Annual Report Document Annual Report Prepaid expenses Prepaid Expenses, Noncurrent Sum of the carrying amounts as of the balance sheet date of amounts paid in advance for expenses which will be charged against earnings in periods after one year or beyond the operating cycle, if longer. Entities [Table] Entities [Table] 837.78 837.78 [Member] This member stands for Exercise price 837.78 Tax receivables Current receivables from taxes other than income tax Percentage of reasonably possible increase in actuarial assumption Percentage of reasonably possible increase in actuarial assumption Geographical areas [domain] Geographical areas [domain] 648.60 648.60 [Member] 648.60 Schedule of property, plant and equipment Disclosure of reconciliation of changes in property, plant and equipment, including right-of-use assets [text block] Trade and other receivables Total trade and other receivables Trade and other current receivables New shares issued for private placement, initial public offering, public offering and underwriters' over-allotment option (in shares) Increase (decrease) in number of shares outstanding Due To New Shares Issued For Private Placement Initial Public Offering And Public Offering The increase (decrease) in the number of shares outstanding due to new shares issued for, but not limited to, private placement, initial public offering or public offering. Entity Interactive Data Current Entity Interactive Data Current 159.51 159.51 [Member] 159.51 2025 2025 [Member] This member stands for Expiry date 2025. Number of operating segments Number of Operating Segments1 An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. Disclosure of attribution of expenses by nature to their function [line items] Disclosure of attribution of expenses by nature to their function [line items] Levels of fair value hierarchy [axis] Levels of fair value hierarchy [axis] Total equity attributable to owners of the parent Equity attributable to owners of parent [member] Financial expense Finance costs Material Accounting Policy Information Disclosure of material accounting policy information [text block] Effect of share-based payment expenses that are not deductible in determining taxable results Tax Effect Of Share Based Payment Expenses Not Deductible In Determining Taxable Profit Tax The amount that represents the difference between the tax share based payment expense and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to share based payments not deductible in determining taxable profit (tax loss). Cash and bank balances Cash and Cash Equivalents1 [Member] Represents the information pertaining to cash and cash equivalents. Personnel expenses Employee Benefit Expenses Classified as General and Administrative Expenses The expense of all forms of consideration given by an entity in exchange for a service rendered by employees or for the termination of employment classified as general and administrative expenses. Customer [Domain] Customer [Domain] CIK Entity Central Index Key Undistributed earnings attributable to foreign subsidiaries Estimated Undistributed Earnings For Which No Provision For Deferred Tax Liabilities Recognized The amount of estimated undistributed earnings for which no provision for deferred tax liabilities recognized. Schedule of auditor's fees expensed Disclosure of Auditor's Fees Expensed in Income Statement [Table Text Block] The disclosure of auditors' fees were expensed in the income statement. Schedule of difference between provision for income taxes and amount that result from applying statutory tax rate to income before provision for income taxes Ifrs Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations. Cash and Cash Equivalents Disclosure of cash and cash equivalents [text block] Outstanding stock options (in shares) Beginning balance (in shares) Ending balance (in shares) Outstanding (in shares) Number of share options outstanding in share-based payment arrangement Professional fees Professional fees expense Profit/(Loss) for the year attributable to: Profit (loss), attributable to [abstract] Equity and liabilities Equity and liabilities [abstract] Net exposure to exchange differences of the monetary assets Risk exposure associated with instruments sharing characteristic Entity Filer Category Entity Filer Category 420.06 420.06 [Member] 420.06 Vesting Right [Domain] Vesting Right [Domain] Vesting Right [Domain] Payroll tax rebates Payroll Tax Rebates The amount of payroll tax rebates. Transfer out of level 3 liabilities Transfers out of Level 3 of fair value hierarchy, liabilities Increase (decrease) in financial instrument due to reasonably possible decrease in designated risk component Increase Decrease In Financial Instrument Due To Reasonably Possible Decrease In Designated Risk Component The increase (decrease) in a financial instrument as a result of a decrease in a designated risk component that was reasonably possible at the end of the reporting period. Excludes defined benefit plan obligations. Operating profit/(loss) Operating profit/(loss) Profit (loss) from operating activities Entity Address, Address Line Three Entity Address, Address Line Three Other receivables Other current receivables Audit fees Auditor's remuneration for audit services Entity Address, Address Line One Entity Address, Address Line One Provision for deferred tax liabilities Balance at beginning of period Balance at end of period Net deferred tax liabilities Entity Address, Address Line Two Entity Address, Address Line Two Distribution fees, product returns Distribution Fees And Product Returns [Member] This member stands for Distribution fees, product returns and other. Leases Disclosure of leases [text block] Investment in a joint venture Other cash payments to acquire interests in joint ventures, classified as investing activities Product net sales Total product net sales Revenue from sale of goods Personnel Expenses Disclosure of personnel expenses [text block] The disclosure of personnel expenses. Commitments to acquire property, plant and equipment Contractual commitments for acquisition of property, plant and equipment Non-executive director Non-Executive Director [Member] Non-Executive Director Statement of cash flows [abstract] Disclosure of financial assets [table] Disclosure of financial assets [table] Prepaid Expenses (Current) Disclosure Of Prepaid Expenses, Current [Text Block] The entire disclosure of prepaid expenses, current. Innovation income deduction credit Innovation Income Deduction [Member] Innovation Income Deduction Income tax prior years Adjustments for current tax of prior periods Disclosure of maturity analysis of finance lease payments receivable [table] Disclosure of maturity analysis of finance lease payments receivable [table] Counterparty Name [Domain] Counterparty Name [Domain] 13.37 - 16.61 Exercise Price 13.37 - 16.61 [Member] Exercise Price 13.37 - 16.61 Germany GERMANY Post‑employment benefits Post-employment benefit expense in profit or loss, defined benefit plans Effect of different tax rates in jurisdictions in which the company operates Tax effect of foreign tax rates Non-current restricted assets Non-current restricted cash and cash equivalents Board fees and other short-term benefits for Non-Executive Directors Key Management Personnel Board Fees and Other Short Term Benefits Key Management Personnel Board Fees and Other Short Term Benefits . 13.37 13.37 [Member] This member stands for Exercise price 13.37 Current liabilities Current liabilities [abstract] Brazil BRAZIL Onco Verity Inc. Joint Venture Onco Verity Inc. Joint Venture [Member] This member stands for Onco Verity Inc. Joint Venture. Derecognition of intangible assets Derecognition of Intangible Assets Other Than Goodwill The decrease in intangible assets other than goodwill resulting from derecognition. Disclosure of transactions between related parties [line items] Disclosure of transactions between related parties [line items] Financial instruments and financial risk management Disclosure of fair value measurement of assets [line items] Commitments to acquire additional intangible assets Contractual commitments for acquisition of intangible assets Canada CANADA Australia SWITZERLAND Personnel expenses [Abstract] n/a Acquired R&D available for use Acquired Research And Development Available For Use [Member] This member stands for acquired intangible assets available for use. Classes of share capital [domain] Classes of share capital [domain] Percentage of reasonably possible decrease in actuarial assumption Percentage of reasonably possible decrease in actuarial assumption Non-current financial assets Non-current financial assets at fair value through other comprehensive income Schedule of cash and cash equivalents Disclosure of Detailed Information About Cash and Cash Equivalents [Table Text Block] Tabular disclosure of cash and cash equivalents. China CHINA Number of shares on conversion (in shares) Conversion of Stock, Shares Issued The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. Contact Personnel Email Address Contact Personnel Email Address Schedule of selling, general and administrative expenses Disclosure of Detailed Information About Selling General And Administrative Expense [Table Text Block] Tabular disclosure of selling, general and administrative expenses Proceeds from issue of new shares, gross amount Proceeds from issue of ordinary shares Australia AUSTRALIA Financial income Finance income Austria AUSTRIA Classes of financial liabilities [axis] Classes of financial liabilities [axis] Classes of financial liabilities [domain] Classes of financial liabilities [domain] Document Shell Company Report Document Shell Company Report Additions to right-of-use assets Additions to right-of-use assets Cost of merchandise sold Cost of merchandise sold Total number of FTEs Average number of employees Belgium Belgium BELGIUM 2026 2026 [Member] This member stands for Expiry date 2026. Lease liabilities Total carrying amount Lease liabilities Property, plant and equipment subject to operating leases Property, plant and equipment subject to operating leases [member] Current financial assets Current financial assets measured at fair value through other comprehensive income Schedule of trade and other payables Disclosure of trade and other payables [table text block] The entire disclosure of trade and other payables. Recognized in equity Deferred Tax Expense Recognized In Equity Deferred Tax Expense Recognized In Equity Minimum Minimum [Member] Statement of compliance and basis of preparation Statement Of Compliance And Basis Of Preparation [Text Block] The entire disclosure of information pertaining to basis of presentation. Reclassification Increase (decrease) through transfers, intangible assets other than goodwill Schedule of restricted and performance stock units arrangements Disclosure of number and weighted average exercise prices of other equity instruments [text block] Trade and other receivables Description of accounting policy for trade and other receivables [text block] 133.35 - 159.51 Exercise Price 133.35 - 159.51 [Member] Exercise Price 133.35 - 159.51 Share capital Issued capital argenx B.V. argenx B.V. ARGENX BV Subsidiary [Member] This member stands for ARGENX BVBA. Unrecognized tax losses carried forward Unused tax losses for which no deferred tax asset recognised Other Intangibles Other intangible assets [member] Other operating income - collaboration and license agreements Description Of Accounting Policy For Collaborations and License Agreements [Policy Text Block] The description of the entity's material accounting policy information for collaborations and license agreements. Trade and other payables Trade and other payables [Member] This member stands for trade and other payables. Categories of financial assets [axis] Categories of financial assets [axis] argenx Brasil Produtos Farmacêuticos Ltda​ Argenx Brasil Produtos Farmacêuticos Ltda​ [Member] Argenx Brasil Produtos Farmacêuticos Ltda​ Additions of the year Non Current Financial Assets Acquired, During Period The amount of non current financial assets acquired during the reporting period. Number of shares outstanding (in shares) Number of shares outstanding at beginning of period (in shares) Number of shares outstanding at end of period (in shares) Number of shares outstanding Term accounts Term Accounts The amount of term accounts. 2028 2028 [Member] This member stands for Expiry date 2028. Other expenses Other expense, by function Other Other temporary differences [member] Income tax benefit Total income tax benefit Tax expense (income) Credits or payments Accruals, Decrease From Credit or Payments Related to Sales Amount of decrease in accruals from payment or credit from sales made during the period. Events After the Balance Sheet Date Disclosure of events after reporting period [text block] Sale of current financial assets Proceeds from sales or maturity of financial instruments, classified as investing activities Document Transition Report Document Transition Report Effect of stock issue expenses that are not taxable in determining taxable results Tax Effect of Stock Issue Expenses Not Deductible in Determining Taxable Profit Tax Loss The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to stock issue expenses not deductible in determining taxable profit (tax loss). Materials and consumables Raw Materials And Consumables Used In Research And Development Represents raw materials and consumables expenses incurred in the R&D process. Miscellaneous non-current assets [abstract] Selling, general and administrative expenses Total Selling, general and administrative expenses Selling, general and administrative expense Document Period End Date Document Period End Date Other short term benefits Key management personnel compensation, Other Short Term Employee Benefits The amount of compensation to key management personnel in the form of other short-term employee benefits. Disclosure of classes of share capital [line items] Disclosure of classes of share capital [line items] Maturity [axis] Maturity [axis] Fair value movement on investment in equity instruments designated as at FVTOCI Investments in equity instruments designated at fair value through other comprehensive income [member] Germany UNITED KINGDOM Selling, General and Administrative Expenses Disclosure of Selling General and Administrative Expenses [Text Block] The entire disclosure for selling, general and administrative expenses. Document Type Document Type 430.17 430.17 [Member] 430.17 Total share based payment expense Expense from share-based payment transactions with employees Product and Service [Axis] Product and Service [Axis] Spain SPAIN Classes of financial assets [axis] Classes of financial assets [axis] Total contractual cash flows Gross lease liabilities Loss from investment in a joint venture Share of profit (loss) of joint ventures accounted for using equity method Share price (in EUR per share) Share price (in USD/EURO per share) Ifrs Share Price Price of a single share of a number of saleable stocks of a company. Rest of the World Rest of the World Rest Of The World [Member] Rest Of The World Future milestone payments Future Milestone Payments All Targets The amount of future milestone payments too be made for all targets. Types of share-based payment arrangements [domain] Types of share-based payment arrangements [domain] France FRANCE Earnings per share [abstract] Earnings per share [abstract] Currently stated Currently stated [member] Range [axis] Range [axis] Components of equity [axis] Components of equity [axis] Entity Information [Line Items] Entity Information [Line Items] Profit/(Loss) for the year before taxes (Profit)/Loss before taxes Profit (loss) before tax Over-allotment option exercised by underwriters Underwriters' Over Allotment Option [Member] Represents information pertaining to underwriter's over allotment option. Net cash proceeds Net proceeds from the issue of shares The cash inflow from net proceeds from issuing shares. Incentive refund period (in years) Refund Period of Research and Development Incentives Period for refund of research and development incentives. 133.35 133.35 [Member] 133.35 Financial assets - current [Abstract] N/A Share Capital and Share Premium Disclosure of share capital, reserves and other equity interest [text block] Increase/decrease in interest rates Increase Decrease in Basis Points Increase Decrease in Basis Points Other Operating Income Disclosure of other operating income [text block] Categories of related parties [domain] Categories of related parties [domain] Weighted average Grant Date Fair Value - January 1 (in USD per share) Weighted average Grant Date Fair Value - December 31 (in USD per share) Weighted average exercise price of other equity instruments outstanding in share-based payment arrangement Depreciation of property, plant and equipment Adjustments for depreciation expense Auditor Location Auditor Location Intangible assets Intangible Assets [Member] This member stands for temporary differences from intangible assets. Payments of stock issuance costs IFRS Payments of Stock Issuance Costs The cash outflow for cost incurred directly with the issuance of an equity security. Depreciation and amortization Depreciation And Amortization Expense Research And Development Represents depreciation and amortization of assets used in research and development. Collaboration revenue Revenue from rendering of services Weighted average number of shares used for basic profit/(loss) per share (in shares) Weighted average number of shares used for basic profit/(loss) per share (in shares) Weighted average number of ordinary shares used in calculating basic earnings per share Money market funds Money Market Funds The amount of money market funds. Number of new targets to be in-licensed Number of New Targets In-Licensed Number of New Targets In-Licensed Schedule of amount of deferred tax assets and liability by type of temporary difference Disclosure of temporary difference, unused tax losses and unused tax credits [text block] Cash equivalents Cash Equivalents1 [Member] Represents the information pertaining to Cash equivalent. Employer social security cost related to stock options Key Management Personnel Compensation Employer Social Security Contributions Stock Options The amount of compensation to key management personnel in the form of employer social security contributions on stock option awards granted. Disclosure of detailed information about intangible assets [table] Disclosure of detailed information about intangible assets [table] Other reserves Other reserves Change in fair value on non-current financial assets Gains (losses) on financial assets at fair value through profit or loss Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Carried forward Netherlands Country of domicile [member] Exercisable at end of year (in shares) Number of share options exercisable in share-based payment arrangement IT equipment Computer equipment [member] Number of share options granted being used to pay tax by transferring the economic benefits (in shares) Number of share options granted in share-based payment arrangement used to pay tax Number of share options granted in share-based payment arrangement being used to pay tax by transferring the economic benefits Share‑based payment Expenses from Share Based Payment Transactions The amount of expenses relating to share based payment transactions. argenx Germany GmbH ARGENX GERMANY GMBH [Member] Argenx Germany GmbH Weighted average Grant Date Fair Value - Vested (in USD per share) Weighted average exercise price of other equity instruments exercised or vested in share-based payment arrangement Net cash flows from financing activities Cash flows from (used in) financing activities Counterparties [axis] Counterparties [axis] Income taxes [Abstract] n/a Financial Risk Management Disclosure of nature and extent of risks arising from financial instruments [text block] Current financial assets Description of accounting policy for financial assets [text block] Entity Current Reporting Status Entity Current Reporting Status Statement of changes in equity [table] Statement of changes in equity [table] Japan Japan Japan JAPAN General information about the company [Abstract] N/A Vesting period (in years) Vesting Requirements For Share-Based Payment Arrangement, Vesting Period Vesting Requirements For Share-Based Payment Arrangement, Vesting Period Performance stock units (PSUs) Performance Stock Units (PSUs) [Member] Performance Stock Units (PSUs) Schedule of product net sales by country of sales Disclosure of products and services [text block] Foreign currency translation differences Accruals, Foreign Currency Translation Adjustment Accruals, Foreign Currency Translation Adjustment Cost of sales Cost of sales 400.32 400.32 [Member] 400.32 Disclosure of subsidiaries [abstract] Current Fiscal Year End Date Current Fiscal Year End Date Profit in inventory Profit in Inventory [Member] This member stands for temporary differences for profit in inventory. Schedule of income taxes recognized in income statement Ifrs Schedule Of Income Taxes Recognized in Income [Table Text Block] Tabular disclosure of income taxes recognized in income. Non-current fixed assets Non-Current Fixed Assets [Member] This member stands for temporary differences from Non-current fixed assets. Bottom of range Bottom of range [member] Total capital Gross Issued Capital The gross amount of capital issued, including amount received or receivable from the issuance of the entity's shares in excess of nominal value. Sales rebates and reserves Sales rebates and reserves. beginning balance Sales rebates and reserves, ending balance Accruals Disclosure of major customers [table] Disclosure of major customers [table] Amortized cost Financial liabilities at amortised cost, category [member] Categories of related parties [axis] Categories of related parties [axis] Average fair value of options (in USD per share) Weighted average fair value at measurement date, per share options granted Weighted average fair value at measurement date, per share options granted. Italy ITALY Fair value adjustment of the year through profit or loss Non Current Financial Assets Fair Value Adjustments, During Period The amount of fair value adjustments for non current financial assets incurred during the reporting period. Total non-current assets Property Plant and Equipment Including Right-of-Use Assets and Intangible Assets Non current Assets exclude deferred tax assets. Profit/(Loss) for the year Profit/(Loss) for the year Profit (loss) for the year Profit (loss) argenx Japan KK. ARGENX JAPAN KK [Member] Argenx Japan KK. Granted (in USD per share) Weighted average exercise price of share options granted in share-based payment arrangement Schedule of movement in sales rebates and reserves Schedule of Movement in Gross to Net Accruals [Table Text Block] Tabular disclosure of movements in gross to net accruals. Total non-current liabilities Non-current liabilities Portugal PORTUGAL Belgian taxed beneficiaries Belgian Taxed Beneficiaries [Member] This member stands for Belgian Taxed Beneficiaries. Document Registration Statement Document Registration Statement Number of shares issued (in shares) Number of shares issued Schedule of consolidated statements of profit or loss and other comprehensive income or loss relating to leases Lessee, Operating Lease Liabilities Recognized In Statement Of Financial Position [Table Text Block] Tabular disclosure of the total lease liabilities recognized in our statement of financial position. Contingencies Disclosure of contingent liabilities [text block] Segment Reporting Disclosure of entity's operating segments [text block] Depreciation charges Depreciation, right-of-use assets Temporary difference, unused tax losses and unused tax credits [domain] Temporary difference, unused tax losses and unused tax credits [domain] Outstanding commitment Capital commitments Depreciation and impairment Amortization and impairment Accumulated depreciation and amortisation [member] Accumulated losses Retained earnings [member] Deferred tax benefit Deferred tax expense (income) relating to tax rate changes or imposition of new taxes Effect of tax credits and incentives Tax Effect of Tax Credits And Incentives The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to concessions and grants in determining taxable profit (tax loss). Leases Description of accounting policy for leases [text block] Schedule of change in net deferred taxes Schedule of Changes In Deferred Taxes [Table Text Block] Tabular disclosure of reconciliation of changes in deferred tax liability (asset). Variable pay Key Managerial Personal Compensation, Variable Pay The amount of variable compensation to key management personnel. Analysis of income and expense [abstract] Business Contact Business Contact [Member] Critical accounting estimates and judgments [Abstract] n/a Categories of financial assets [domain] Categories of financial assets [domain] Carrying amount Carrying amount [member] Sale of Stock [Axis] Sale of Stock [Axis] Information by type of sale of the entity's stock. Property, plant and equipment Property, Plant and Equipments [Member] This member stands for temporary differences from property, plant and equipment. Prepaid advertising expenses Prepaid Advertising Expenses, Current The amount of prepaid advertising expenses, current. the Netherlands NETHERLANDS Security Exchange Name Security Exchange Name 290.93 290.93 [Member] 290.93 Senior management Senior management [Member] This member stands for executive directors. Forfeited (in shares) Number of share options forfeited in share-based payment arrangement 432.99 432.99 [Member] 432.99 Disclosure of terms and conditions of share-based payment arrangement [abstract] Disclosure of terms and conditions of share-based payment arrangement [abstract] argenx Spain S.L. Argenx Spain S.L. [Member] This member stands for Argenx Spain S.L. Global public offering on Nasdaq Global Offering [Member] This member stands for Global offering. Provisions for employee benefits Non-current provisions for employee benefits Right-of-use assets Right-of-use assets Trade and other receivables Trade and other receivables [Member] This member stands for Trade and Other Receivables. Contact Personnel Name Contact Personnel Name Cost of stock options granted in the year for the Senior Management Team Share Options Granted, Value The amount of stock options granted in a year. Carrying amount of assets under IFRS 9 Financial assets, carrying amount immediately after initial application of IFRS 9 Holding period (in years) Vesting Requirements For Share-Based Payment Arrangement, Holding Period Vesting Requirements For Share-Based Payment Arrangement, Holding Period Vesting period (in years) Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Schedule of non-current assets Disclosure of geographical areas [text block] Items that may be reclassified subsequently to profit or loss, net of tax Components of other comprehensive income that will be reclassified to profit or loss, net of tax [abstract] Assets carried at fair value Financial assets, at fair value Restricted stock units (RSUs) Restricted Stock Units (RSUs) [Member] Share instrument which is convertible to stock or an equivalent amount of cash, after a specified period of time or when specified performance conditions are met. Schedule of research and development expenses Disclosure of Detailed Information About Research and Development Expense [Table Text Block] Disclosure of Detailed Information About Research and Development Expense Four customers Four Customers [Member] Four Customers Effect of change of (de)recognition of deferred tax assets on tax losses Tax Effect of Tax Losses Carried Forward not Recognized The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to tax losses carried forward not recognized in determining taxable profit (tax loss). Term accounts Term Accounts [Member] This member stands for Term Accounts. Translation differences Reserve of exchange differences on translation [member] Effect of foreign exchange translation Tax Effect of Withholding Tax The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to withholding tax in determining taxable profit (tax loss). Total operating expenses Operating expense Intangible assets, useful life (in years) Useful life measured as period of time, intangible assets other than goodwill Income tax benefit from excess tax deductions related to share-based payments Decrease (increase) through tax on share-based payment transactions, equity Classes of share capital [axis] Classes of share capital [axis] Exercised (in shares) Number of share options exercised in share-based payment arrangement Effect of expenses not deductible in determining taxable results Tax effect of expense not deductible in determining taxable profit (tax loss) 140.45 - 290.93 Exercise Price 140.45 - 290.93 [Member] Exercise Price 140.45 - 290.93 13.44 13.44 [Member] This member stands for Exercise price 13.44 Total equity Equity at beginning of period Equity at end of period Equity Entity Addresses, Address Type [Axis] Entity Addresses, Address Type [Axis] Efgartigimod Efgartigimod [Member] Represents information pertaining to efgartigimod. Collaborative arrangement maximum regulatory milestone payments to be received on exercise of option Collaborative Arrangement Maximum Regulatory Milestone Payments to be Received on Exercise of Option The maximum amount of payment to be received for regulatory milestone on exercise of option. 2027 2027 [Member] This member stands for Expiry date 2027. Commitments Disclosure of commitments [text block] Share based compensation award tranche two Share Based Compensation Awards, Tranche Two [Member] Share Based Compensation Awards, Tranche Two argenx France SAS ARGENX FRANCE SAS [Member] Argenx France SAS Items that will not be reclassified subsequently to profit or loss, net of tax Components of other comprehensive income that will not be reclassified to profit or loss, net of tax [abstract] Level 1 Level 1 of fair value hierarchy [member] Effects of change in foreign exchange rate Increase (Decrease) Through Exchange Difference Deferred Tax Liability The amount of tax income relating to changes in increase (decrease) through exchange difference deferred tax liability. Granted (in shares) Number of options granted (in shares) Numbers of stock options granted in the year (in shares) Number of share options granted in share-based payment arrangement Disclosure of detailed information about property, plant and equipment [line items] Financial position relating to leases Disclosure of detailed information about property, plant and equipment [line items] 8.43 8.43 [Member] This member stands for Exercise price 8.43 Undrawn borrowing facilities Undrawn borrowing facilities Level 2 Level 2 of fair value hierarchy [member] Disclosure of non-adjusting events after reporting period [abstract] Fair value adjustments at beginning Fair value adjustments at ending Non Current Financial Assets, Fair Value Adjustments The amount of fair value adjustments for non current financial assets as at the end of reporting period. Beginning balance (in USD per share) Ending balance (in USD per share) Weighted average exercise price of share options outstanding in share-based payment arrangement Movements in current assets/liabilities Movements in Current Assets or Liabilities [Abstract] No definition available. Owners of the parent Profit (loss), attributable to owners of parent argenx UK Ltd. Argenx UK Ltd. [Member] Argenx UK Ltd. Marketing services Sales and marketing expense Provisions for employee benefits Adjustments for provisions Positive/negative impact Change In Impact Due To Increase Decrease In Basis Points Positive or negative impact due to increase or decrease in basis points. Deferred tax assets Deferred tax assets [Abstract] No definition available. Stock options Stock Option Plan [Member] Stock Options Net deferred tax assets/(liabilities) Deferred tax liability (asset) Other non-cash expenses/(benefit) Other adjustments for non-cash items Total current liabilities Current liabilities Trade and other receivables [abstract] Transfer into level 3 assets Transfers into Level 3 of fair value hierarchy, assets Inventories Total inventories Current inventories Deferred tax assets Deferred tax assets Deferred tax assets Document Accounting Standard Document Accounting Standard 2035 2035 [Member] 2035 Income taxes - Deferred tax assets Disclosure of temporary difference, unused tax losses and unused tax credits [line items] Weighted average remaining contractual life (in years) Weighted average remaining contractual life of outstanding share options Disclosure of quantitative information about right-of-use assets Disclosure of quantitative information about right-of-use assets [line items] Share-based payments Description of accounting policy for share-based payment transactions [text block] Statement of changes in equity [abstract] Accumulated losses Retained earnings EY Accountants B.V. EY Accountants B.V. [Member] EY Accountants B.V. argenx Netherlands Services B.V. ARGENX NETHERLANDS B.V [Member] ARGENX NETHERLANDS B.V Buildings Right-of-use assets Buildings Buildings Buildings [member] Number of RSUs - Granted (in shares) Numbers of stock units granted in the year (in shares) Number of PSUs - Granted (in shares) Number of other equity instruments granted in share-based payment arrangement Types of risks Types of risks [domain] Loss from investment in a joint venture Adjustments for gain (loss) on disposal of investments in subsidiaries, joint ventures and associates Employer social security contributions share-based payments Expenses from Employer Social Security Contribution Stock Options The amount of expenses relating to employer social security contribution stock options. (Increase)/decrease in trade and other receivables Adjustments for decrease (increase) in trade and other receivables Legal Entity [Axis] Legal Entity [Axis] Cash and bank balances Cash and Bank Balances The amount of cash and bank balances. Subsidiaries [axis] Subsidiaries [axis] Profit/(Loss) for the period Profit (loss), attributable to ordinary equity holders of parent entity, used in calculating basic earnings per share Research and development incentives Research and Development Incentives The amount of tax receivables as research and development incentives. Interest paid Interest paid, classified as operating activities JPY Japan, Yen 2.87 2.87 [Member] This member stands for Exercise price 2.87 Current prepayments [abstract] Geographical areas [axis] Geographical areas [axis] argenx Italy S.r.l. ARGENX ITALY [Member] This member stands for ARGENX ITALY. Auditor [Table] Auditor's Remuneration [Table] Auditor's Remuneration Lease liabilities Non-current Non-current lease liabilities Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Intangible assets Intangible assets other than goodwill at beginning of period Intangible assets other than goodwill at end of period Intangible assets other than goodwill Document Financial Statement Error Correction [Flag] Document Financial Statement Error Correction [Flag] 21.63 21.63 [Member] 21.63 Maximum authorized increase in share capital Maximum Authorized Increase in Share Capital The maximum authorized increase in share capital. Disclosure of fair value measurement of assets [table] Disclosure of fair value measurement of assets [table] Disposals Disposals, intangible assets other than goodwill Property, plant and equipment by operating lease status [axis] Property, plant and equipment by operating lease status [axis] Cash and cash equivalents Cash and cash equivalents at the beginning of the year Cash and cash equivalents at the end of the year Total cash and cash equivalents Cash and cash equivalents Prepaid research and development expenses Prepaid Research And Development Expenses, Current The amount of prepaid research and development expenses, current. Translation differences Reserve of exchange differences on translation Other prepaid expenses Other Prepaid Expenses, Current The amount of other prepaid expenses, current. Total equity and liabilities Equity and liabilities United States United States USA UNITED STATES 230.48 230.48 [Member] 230.48 Other tax carryforwards Other Tax Carry Forwards [Member] This member stands for Other tax carryforwards. Assets are pledged as security for liabilities Property, plant and equipment, pledged as security American depositary shares American Depositary Shares [Member] Represents information pertaining to American depositary shares. Product and Service [Domain] Product and Service [Domain] Schedule of weighted average remaining contractual life for each range of exercise price Disclosure of range of exercise prices of outstanding share options [text block] Disclosure of reconciliation of changes in property, plant and equipment, including right-of-use assets [line items] Disclosure of reconciliation of changes in property, plant and equipment, including right-of-use assets [line items] Disclosure of attribution of expenses by nature to their function [table] Disclosure of attribution of expenses by nature to their function [table] 2031 2031 [Member] This member stands for Expiry date 2031. Joint ventures [domain] Joint ventures [domain] Short‑term employee benefits Short-term employee benefits accruals Inventories [Line Items] Inventories [Line Items] Inventories [Line Items] Interest rate risk Interest rate risk [member] Disclosure of initial application of standards or interpretations [abstract] Disclosure of initial application of standards or interpretations [abstract] City Area Code City Area Code IT, office and lab equipment IT, Office And Lab Equipment [Member] IT, Office And Lab Equipment Estimated useful life (in years) Useful life measured as period of time, property, plant and equipment Fair value adjustment of the year through OCI Non Current Financial Assets Fair Value Adjustments Through OCI During Period The amount of fair value adjustments for non current financial assets through OCI incurred during the reporting period. Categories of financial liabilities [domain] Categories of financial liabilities [domain] Greater than 5 years Later than five years [member] Related Party Transactions Disclosure of related party [text block] Classes of financial assets [domain] Classes of financial assets [domain] Capitalized R&D expenses R&D Capitalized Expense [Member] This member stands for temporary differences from R&D capitalized expense. Intangible Assets Disclosure of intangible assets [text block] Level 3 Level 3 of fair value hierarchy [member] Disposals Disposals, property, plant and equipment including right-of-use assets Interest expense (included in finance cost) Interest expense on lease liabilities Additions Acquisitions through business combinations, intangible assets other than goodwill Critical accounting judgments and major sources of estimation uncertainty Disclosure of accounting judgements and estimates [text block] Exchange (losses)/gains from currency conversion on proceeds from issue of new shares Exchange Gain From Currency Conversion On Proceeds From Issue Of New Shares The amount of gain (loss) on foreign currency conversion on proceeds from issuance of new shares Prepaid software Prepaid Software, Current The amount of prepaid software, current. Ifrs Grantee Status [Domain] Ifrs Grantee Status [Domain] Status of recipient to whom award is granted. Disclosure of classes of share capital [table] Disclosure of classes of share capital [table] Auditor Name Auditor Name 2030 2030 [Member] This member stands for Expiry date 2030. Carrying amount of liabilities under IFRS 9 Financial liabilities, carrying amount immediately after initial application of IFRS 9 94.96 94.96 [Member] 94.96 Investment in a joint venture Investments in joint ventures reported in separate financial statements Collaborative arrangement maximum additional development milestone payments to be received on exercise of option Collaborative Arrangement Maximum Additional Development Milestone Payments to be Received on Exercise of Option The maximum amount of payment to be received for additional development milestone on exercise of option. Trade and Other Receivables Disclosure of trade and other receivables [text block] Non-executive directors Non-executive Directors [Member] This member stands for non-executive directors. Time period for beneficiaries to choose contractual term (in years) Time Period to Choose Different Contractual Terms Time period given to beneficiaries to choose different contractual term under share-based compensation, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Average Expected option life (in years) Option life, share options granted Disclosure of major customers [line items] Disclosure of major customers [line items] 11.13 11.13 [Member] This member stands for Exercise price 11.13 Net cash flows from/(used) in operating activities Cash flows from (used in) operating activities Finished goods Current finished goods Number of RSUs - Forfeited (in shares) Number of PSUs - Forfeited (in shares) Number of other equity instruments forfeited in share-based payment arrangement Disclosure of terms and conditions of share-based payment arrangement [line items] Disclosure of terms and conditions of share-based payment arrangement [line items] Non-current liabilities Non-current liabilities [abstract] Halozyme Therapeutics Inc Halozyme Therapeutics Inc [Member] Halozyme Therapeutics Inc Entity [Domain] Entity [Domain] Share-Based Payments Disclosure of share-based payment arrangements [text block] Other operating income Total other operating income Miscellaneous other operating income Disclosure of detailed information about intangible assets [abstract] Document Fiscal Year Focus Document Fiscal Year Focus Adjustments for non-cash items Adjustments to reconcile profit (loss) [abstract] Research and Development Expenses Disclosure of research and development expense [text block] Research and development incentive receivables Research and Development Incentive Receivables, Current The amount of research and development incentive receivables including tax incentives classified as current. Leasehold improve­ments Leasehold improvements [member] Equipment Leased equipment Equipment Lease equipment [Member] This member stands for lease equipment. Trade payables Current trade payables Schedule of net exposure to exchange differences of monetary assets Sensitivity analysis for types of market risk [text block] Total benefits for key management personnel Key management personnel compensation Weighted average exercise price Weighted average exercise price [Abstract] n/a AbbVie AbbVie [Member] This member stands for AbbVie S.A.R.L. Classes of current inventories [abstract] Ordinary shares Ordinary shares [member] Trade receivables Current trade receivables Accruals and allowances Allowance for credit losses [member] Audit Fees Disclosure of auditors' remuneration [text block] Earnings per Share Disclosure of earnings per share [text block] Cost Cost Gross carrying amount [member] Trade and other payables Total trade and other payables Trade and other current payables Deferred tax liabilities Reconciliation of Changes In Deferred Tax Liability [Abstract] No definition available. Auditor's remuneration [abstract] Inventories Disclosure of inventories [text block] Property, plant and equipment by operating lease status [domain] Property, plant and equipment by operating lease status [domain] Increase/(decrease) in cash and cash equivalents Increase Decrease In Cash And Cash Equivalents Excluding Exchange Gain Loss the increase (decrease in cash and cash equivalents excluding exchange gain (loss). 2030-2035 2030-2035 [Member] 2030-2035 Local Phone Number Local Phone Number Proceeds from issue of shares Gross proceeds from issue of shares Proceeds from issuing shares Less than 1 year Not later than one year [member] Selling, general and administrative expense [abstract] Number of stock options Number of stock options [Abstract] n/a Disclosure of detailed information about property, plant and equipment [abstract] Total Auditor's remuneration Cash and cash equivalents Cash Equivalents At Fair Value Fair value portion of cash equivalents. (Increase)/decrease in inventories Adjustments for decrease (increase) in inventories Disclosure of financial assets [line items] Disclosure of financial assets [line items] Property, plant and equipment Property, plant and equipment [member] Netting by taxable entity Netting by Taxable Entity [Member] This member stands for temporary differences from netting by taxable entity. Principal elements of lease payments Payments of lease liabilities, classified as financing activities Entity Voluntary Filers Entity Voluntary Filers Proportion of ownership interest in subsidiary (as percent) Proportion of ownership interest in subsidiary Share-based payments Income Tax Benefit Related To Share-Based Payments [Member] Income tax benefit from excess tax deductions related to share-based payments. Current estimate related to the sales made in the current year Accruals, Increase From Sales Amount of increase in accruals from sales made during the period. Weighted average Grant Date Fair Value - Forfeited (in USD per share) Weighted average exercise price of other equity instruments forfeited in share-based payment arrangement Grantee Award Status [Axis] Grantee Award Status [Axis] Grantee Award Status Entity Registrant Name Entity Registrant Name Basic profit/(loss) per share (in USD per share) Basic profit/(loss) per share (in USD per share) Basic earnings (loss) per share Schedule of inventories Schedule Of Current Inventory [Table Text Block] Tabular disclosure of information pertaining to current inventories. Disclosure of risk management strategy related to hedge accounting [table] Disclosure of risk management strategy related to hedge accounting [table] 350.97 - 541.21 Exercise Price 350.97 - 541.21 [Member] Exercise Price 350.97 - 541.21 Weighted average number of shares used for diluted profit/(loss) per share (in shares) Weighted average number of shares used for diluted profit/(loss) per share (in shares) Weighted average number of ordinary shares used in calculating diluted earnings per share Exercise of stock options Increase (Decrease) Through Exercise Of Options, Equity The increase (decrease) in equity resulting from exercise of options. Originating and reversal of temporary differences Deferred tax expense (income) relating to origination and reversal of temporary differences Classes of intangible assets other than goodwill [domain] Classes of intangible assets other than goodwill [domain] Schedule of parameters used in relation to the new grants Disclosure of Parameters Used in Relation to New Grants [Table Text Block] The disclosure of parameters used in relation to the new grants. (Increase)/decrease in non-current prepaid expense Adjustments for Decrease (Increase) in Non Current Prepaid Expenses Adjustments for Decrease (Increase) in Non Current Prepaid Expenses Expense recognized in respect of share-based payments Adjustments for share-based payments Share based compensation award tranche one Share Based Compensation Awards, Tranche One [Member] Share Based Compensation Awards, Tranche One argenx Benelux B.V. Argenx Benelux B.V. [Member] IIP BV. Schedule of current financial assets Schedule of Current Financial Assets [Table Text Block] Tabular disclosure of current financial assets. Exercisable (in USD per share) Weighted average exercise price of share options exercisable in share-based payment arrangement All Currencies [Domain] All Currencies [Domain] Equity Equity [abstract] Interest receivables Current interest receivable Disclosure of operating segments [abstract] Schedule of assets at fair value Disclosure of fair value measurement of assets [text block] Schedule of other operating income Disclosure of Detailed Information about Other Operating Income [Table Text Block] Tabular disclosure of other operating income. Ifrs Sale of Stock [Domain] Ifrs Sale of Stock [Domain] Ifrs Sale of Stock [Domain] Proceeds from exercise of stock options Proceeds from exercise of options Disclosure of transactions between related parties [abstract] 235.26 235.26 [Member] 235.26 Average fair value of options Weighted average fair value at measurement date, share options granted 275.42 275.42 [Member] 275.42 (Increase)/decrease in other current assets Adjustments for decrease (increase) in other current assets Ranges of exercise prices for outstanding share options [domain] Ranges of exercise prices for outstanding share options [domain] FVTOCI Financial assets at fair value through other comprehensive income, category [member] 101.43 101.43 [Member] This member stands for Exercise price 101.43 ICFR Auditor Attestation Flag ICFR Auditor Attestation Flag Period of outstanding share capital (in months) Period of Outstanding Share Capital The period of outstanding share capital. Disclosure of temporary difference, unused tax losses and unused tax credits [table] Disclosure of temporary difference, unused tax losses and unused tax credits [table] Broteio Pharma B.V.​ Broteio Pharma B.V.​ [Member] Broteio Pharma B.V.​ Total cash outflow for leases Cash outflow for leases Short‑term employee benefits - Social Security Social security contributions Amortization of intangible assets Adjustments for amortisation expense Auditor Firm ID Auditor Firm ID Post-employment benefits for the Senior Management Team Key management personnel compensation, post-employment benefits Shareholder's equity Description of Accounting Policy for Shareholder's Equity [Policy Text Block] The description of accounting policy for Shareholder's equity. Other currencies Other currencies [Member] Represents other currencies. Share premium Share premium [member] Disclosure of contingent liabilities [abstract] Owners of the parent Comprehensive income, attributable to owners of parent Financial assets - current Financial assets - current [Member] Represents the information pertaining to current financial asset. Vesting percentage Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Percentage of vesting of share-based compensation awards. Intangible assets are pledged as security Intangible assets pledged as security for liabilities Effects of change in foreign exchange rate Increase (Decrease) Through Exchange Difference Deferred Tax Assets The amount of tax income relating to increase (decrease) through exchange difference deferred tax assets. Total liabilities Liabilities Office and lab equipment Office equipment [member] Disclosure of subsidiaries [table] Disclosure of subsidiaries [table] Maximum authorized increase of then outstanding share capital (as percent) Maximum Percentage of Outstanding Share Capital Percentage of outstanding share capital. 331.94 331.94 [Member] 331.94 Tax liabilities Current tax liabilities, current Effect of change of (de)recognition of deferred tax assets Tax Effect of Recognition or Derecognition The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to recognition or derecognition. Statement of profit or loss and other comprehensive income [abstract] Intangible assets Description of accounting policy for intangible assets other than goodwill [text block] Retrospective application and retrospective restatement [axis] Retrospective application and retrospective restatement [axis] 563.18 563.18 [Member] 563.18 140.45 140.45 [Member] 140.45 Other expenses Other Research And Development Expenses Represents expenses incurred in research and development not separately disclosed. Forfeited (in USD per share) Weighted average exercise price of share options forfeited in share-based payment arrangement Ifrs Inventory Current [Domain] Ifrs Inventory Current [Domain] Ifrs Inventory Current [Domain] 24.87 24.87 [Member] 24.87 Property, plant and equipment Property, plant and equipment at beginning of period Property, plant and equipment at end of period Property, plant and equipment including right-of-use assets Disclosure of maturity analysis of finance lease payments receivable [line items] Disclosure of maturity analysis of finance lease payments receivable [line items] Current year Current tax expense (income) Years 1 through 5 Later than one year and not later than five years [member] Adjustment for prior periods Accruals, Increase (Decrease) From Prior Period Sales Amount of increase in accruals from prior period sales made during the period. Exchange Gains/(Losses) Disclosure of effect of changes in foreign exchange rates [text block] Top of range Top of range [member] 541.21 541.21 [Member] 541.21 Research and development expenses Total Research and development expenses Research and development expense Weighted average share price (in ISD per share) Weighted average share price Other non-current assets Total other non-current assets Other non-current assets 13.48 13.48 [Member] This member stands for Exercise price 13.48 2032 2032 [Member] This member stands for Expiry date 2032. Weighted average Grant Date Fair Value - Granted (in USD per share) Weighted average exercise price of other equity instruments granted in share-based payment arrangement Cost of performance stock units granted in the year for the Senior Management Team Performance Stock Units Granted, Value Performance Stock Units Granted, Value Movements in non-current assets/liabilities Movements in Non Current Assets or Liabilities [Abstract] n/a. Exercise of stock options (in shares) Increase (Decrease) Through Exercise Of Options, Number of Shares Outstanding The increase (decrease) in number of shares outstanding resulting from the exercise of option's. Inventories Description of accounting policy for measuring inventories [text block] Distribution and commercial support expenses Distribution and Commercial Support Expenses Distribution and Commercial Support Expenses Other operating income [Abstract] N/A Joint ventures [axis] Joint ventures [axis] Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis] Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis] Currency risk Currency risk [member] Disclosure of risk management strategy related to hedge accounting [line items] Disclosure of risk management strategy related to hedge accounting [line items] Financial risk management [Abstract] n/a Maximum upside payout percentage Share-Based Payment Agreement, Maximum Upside Payout Percentage Share-Based Payment Agreement, Maximum Upside Payout Percentage Maximum authorized increase in number of shares (in shares) Maximum Authorized Increase in Number of Shares The maximum authorized increase in number of shares. Deferred tax liabilities Deferred tax liabilities Deferred tax liabilities Number of subsidiaries Number of Subsidiaries Number of subsidiaries. Property, plant and equipment including right-of-use assets [axis] Property, plant and equipment including right-of-use assets [axis] Income taxes (paid)/received Income taxes paid (refund), classified as operating activities Other comprehensive profit/(loss), net of income tax Other comprehensive income/(loss) Other comprehensive income Transfer out of level 3 assets Transfers out of Level 3 of fair value hierarchy, assets Counterparties [domain] Counterparties [domain] 2034 2034 [Member] 2034 Schedule of other non-current assets Schedule of Other Non-current Assets [Table Text Block] Tabular disclosure for other non current assets. Types of share-based payment arrangements [axis] Types of share-based payment arrangements [axis] Title of 12(b) Security Title of 12(b) Security Disclosure of subsidiaries [line items] Overview of consolidation scope Disclosure of subsidiaries [line items] Issue of share capital Issue of equity Grantee Award Status [Domain] Grantee Award Status [Domain] Grantee Award Status [Domain] 331.94 - 432.99 Exercise Price 331.94 - 432.99 [Member] Exercise Price 331.94 - 432.99 Payment of employee withholding taxes relating to restricted stock unit awards Payment, Employee Tax Withholding, Share-Based Payment Arrangement Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement. Inventories [Table Text Block] Inventories [Table] Inventories Depreciation Depreciation, property, plant and equipment including right-of-use assets Property, plant and equipment including right-of-use assets [domain] Property, plant and equipment including right-of-use assets [domain] Subsidiaries [domain] Subsidiaries [domain] Audit-related fees Auditors Remuneration, Audit Related Expenses Amount of expenses for auditor recognized during the period for expenses relating to audit. Raw materials and consumables Current raw materials and current production supplies Financial assets Total current financial assets Current financial assets Current financial assets Pre-launch inventory awaiting facility approval Pre-launch inventory awaiting facility approval [Member] The member related to pre-launch subcutaneous efgartigimod. Trade and Other Payables Disclosure of trade and other payables [text block] Commitments [Line Items] Commitments [Line Items] Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Selling, general and administrative Number of Employees in General and Administrative The number of personnel employed in general and administrative functions by the entity during the period. 422.53 422.53 [Member] 422.53 Financial Assets — Current Schedule of categories of financial assets and liabilities Disclosure of financial instruments [text block] Net cash flows from/(used in) investing activities Cash flows from (used in) investing activities Disclosure of detailed information about intangible assets [line items] Disclosure of detailed information about intangible assets [line items] Net book value at ending Non-current financial assets Increase (decrease) in financial instrument due to reasonably possible increase in designated risk component Increase (Decrease) In Financial Instrument Due To Reasonably Possible Increase In Designated Risk Component The increase (decrease) in a financial instrument as a result of an increase in a designated risk component that was reasonably possible at the end of the reporting period. Excludes defined benefit plan obligations. Total personnel expenses Employee benefits expense Amortization Amortization of intangible assets Amortisation, intangible assets other than goodwill Financial instruments Description of accounting policy for financial instruments [text block] Total current assets Current assets Leases [Abstract] Leases1 [Abstract] Leases Abstract Contractual capital commitments Contractual capital commitments Customer [Axis] Customer [Axis] argenx Canada Inc. ARGENX CANADA INC [Member] ARGENX CANADA INC Zai Lab Zai Lab [Member] This member stands for Zai Labs. Adjustments for non-cash items Cash flows from (used in) operations before changes in working capital Effect of intercompany asset deal/transaction Tax Effect of Intercompany Asset Deal or Transaction The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to intercompany asset deal or transaction. Types of risks [axis] Types of risks [axis] Personnel expenses Employee Benefit Expenses Classified as Research and Development Expenses The expense of all forms of consideration given by an entity in exchange for a service rendered by employees or for the termination of employment classified as research and development expenses. Trade and other payables [abstract] Ifrs Inventory Current [Axis] Ifrs Inventory Current [Axis] NA Disclosure of transactions between related parties [table] Disclosure of transactions between related parties [table] Fair value gains on financial assets at fair value through profit or loss Adjustments for fair value losses (gains) Exercised (in USD per share) Weighted average exercise price of share options exercised in share-based payment arrangement Amortized cost Financial assets at amortised cost, category [member] Expected volatility (as percent) Expected volatility, share options granted Property, Plant and Equipment Disclosure of property, plant and equipment [text block] Net deferred tax assets Balance at beginning of period Balance at end of period Net deferred tax assets Schedule of maturity analysis of lease liabilities Disclosure of maturity analysis of operating lease payments [text block] Ifrs Type of Arrangement and Non-arrangement Transactions [Domain] Ifrs Type of Arrangement and Non-arrangement Transactions [Domain] Ifrs Type of Arrangement and Non-arrangement Transactions [Domain] Expected dividends (as percent) Expected dividend as percentage, share options granted Amendment Flag Amendment Flag Components of equity [domain] Components of equity [domain] Argenx BV Argenx BV [Member] This member stands for argenx BV. Total operating income Revenue and other operating income Temporary difference, unused tax losses and unused tax credits [axis] Temporary difference, unused tax losses and unused tax credits [axis] Adoption of new and revised standards Description of Adoption of New and Revised Standards [Policy Text Block] The disclosure of adoption of new and revised standards. Vesting Right [Axis] Vesting Right [Axis] Information by vesting schedule for share-based compensation. Range [domain] Range [domain] Percentage of product net sales from major customers Percentage of entity revenue from major customers from United States The percentage of the entity's revenue. from major customers from United States. 562.47 562.47 [Member] 562.47 Increase/(decrease) in trade and other payables Adjustments for increase (decrease) in trade and other payables Audit Information [Abstract] Audit Information Share options granted (as percent) Percentage of Share Options Granted of Total Share Options Percentage of share options granted out of total share options. Supervisory board Supervisory Board Expenses The amount of fees paid or payable for supervisory board services. Research and development incentive receivables - current Current Research And Development Incentive Receivables [Member] Represents the information pertaining to current research and development incentive receivables. Research and development Number of Employees in Research and Development The number of personnel employed in the research and development function by the entity during the period. Previously stated Previously stated [member] Lonza and Fujifilm Lonza and Fujifilm [Member] Lonza Financial assets - non-current Financial assets - non-current [Member] Represents the information pertaining to non current financial asset. Address Type [Domain] Address Type [Domain] 275.42 - 363.31 Exercise Price 275.42 - 363.31 [Member] Exercise Price 275.42 - 363.31 94.96 - 101.43 Exercise Price 94.96 - 101.43 [Member] Exercise Price 94.96 - 101.43 Lease liabilities Current Current lease liabilities Currency [Axis] Currency [Axis] Diluted profit/(loss) per share (in USD per share) Diluted profit/(loss) per share (in USD per share) Diluted earnings (loss) per share Maturity [domain] Maturity [domain] Schedule of details of consolidated entities Disclosure of subsidiaries [text block] Overview of Consolidation Scope Disclosure of interests in subsidiaries [text block] Five customers Five Customers [Member] Five Customers Categories of financial liabilities [axis] Categories of financial liabilities [axis] Disclosure of terms and conditions of share-based payment arrangement [table] Disclosure of terms and conditions of share-based payment arrangement [table] Gross salary Key Management Personnel Compensation Gross Salary The amount of gross salary to key management personnel. Vehicles Right-of-use assets Vehicles Vehicles Vehicles [member] Net operating loss carryforwards Net Operating Loss Carryforwards [Member] Net Operating Loss Carryforwards 16.61 16.61 [Member] 16.61 Expenses deducted from equity Expenses Deducted from Equity The amount of expenses deducted from equity. Schedule of earnings per share Earnings per share [text block] Counterparty Name [Axis] Counterparty Name [Axis] Disclosure of detailed information about property, plant and equipment [table] Disclosure of detailed information about property, plant and equipment [table] Purchase of intangible assets Purchase of intangible assets, classified as investing activities Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code 417.60 417.60 [Member] 417.60