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Additions Weighted-average number of shares outstanding - diluted to equity holders (in shares) Adjusted weighted average number of ordinary shares outstanding (Increase)/decrease in other current receivables Adjustments for decrease (increase) in other operating receivables Depreciation of property, plant and equipment Adjustments for depreciation expense Change in fair value of conversion feature Adjustments for fair value losses (gains) Finance result, net Adjustments for finance income (cost) (Gain)/loss on sale of fixed assets Adjustments for gain (loss) on disposals, property, plant and equipment (Decrease)/increase in deferred income Adjustments for increase (decrease) in deferred income Changes in net employee defined benefit liability Adjustments for increase (decrease) in employee benefit liabilities Increase/(decrease) in trade and other payables Adjustments for increase (decrease) in trade accounts payable Interest expense Adjustments for interest expense Adjustments to reconcile net income/(loss) for the period to net cash flows: Adjustments to reconcile profit (loss) [abstract] Share-based compensation expense Adjustments for share-based payments Aggregated time bands [member] Corporate tax rate Applicable tax rate Total assets Assets Assets Assets [abstract] Basic income/(loss) for the period attributable to equity holders (in CHF per share) Basic earnings (loss) per share Basic income/(loss) per share (EPS) [Abstract] Basic earnings per share [abstract] Financing obligation [Abstract] Borrowings [abstract] Borrowings by name [axis] Borrowings by name [member] Bottom of Range [Member] Bottom of range [member] Buildings [Member] Buildings [member] Carrying amount, accumulated depreciation, amortization and impairment and gross carrying amount [axis] Carrying amount [member] Cash and cash equivalents [Abstract] Cash [abstract] Cash and cash equivalents Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Company's cash position Net cash flows (used in)/provided by financing activities Cash flows from (used in) financing activities Financing activities Cash flows from (used in) financing activities [abstract] Net cash flows provided by/(used in) investing activities Cash flows from (used in) investing activities Investing activities Cash flows from (used in) investing activities [abstract] Net cash flows (used in)/provided by operating activities Cash flows from (used in) operating activities Operating activities Cash flows from (used in) operating activities [abstract] Cash (used in)/provided by operating activities Cash flows from (used in) operations Total cash outflow for leases Cash outflow for leases Categories of financial assets [axis] Categories of financial liabilities [axis] Categories of related parties [axis] Share capital [Abstract] Change in net defined benefit liability [Abstract] Changes in defined benefit obligation [Abstract] Changes in net defined benefit liability (asset) [abstract] Classes of assets [axis] Assets [member] Classes of property, plant and equipment [axis] Classes of share capital [axis] Share capital [member] Share Capital [member] Translation rate into CHF Closing foreign exchange rate Components of equity [axis] Other comprehensive income/(loss) not to be reclassified to income or loss in subsequent periods (net of tax) Components of other comprehensive income that will not be reclassified to profit or loss, net of tax [abstract] Total comprehensive income/(loss), net of tax Comprehensive income IT Equipment [Member] Computer equipment [member] Deferred research and development costs Contract assets Upfront payment Up-front consideration received Contract liabilities Employer's contribution Employer's contributions Contributions to plan by employer, net defined benefit liability (asset) Employees' contributions Contributions to plan by plan participants, net defined benefit liability (asset) Counterparties [axis] Counterparties [member] 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[text block] Taxation Description of accounting policy for income tax [text block] Share capital and public offerings Description of accounting policy for issued capital [text block] Leases Property, plant and equipment Description of accounting policy for property, plant and equipment [text block] Provisions Description of accounting policy for provisions [text block] Revenue recognition Description of accounting policy for recognition of revenue [text block] Research and development expenses Description of accounting policy for research and development expense [text block] Segment reporting Description of accounting policy for segment reporting [text block] Expected volatility Expected volatility, share options granted Expected term Option life, share options granted Risk free interest rate Risk free interest rate, share options granted Diluted income/(loss) for the period attributable to equity holders (in CHF per share) Diluted earnings (loss) per share Diluted income/(loss) per share (EPS) [Abstract] Convertible shares (in shares) Dilutive effect of convertible instruments on number of ordinary shares Effect of dilutive securities from equity incentive plans (in shares) Dilutive effect of share options on number of ordinary shares Key management compensation Disclosure of amounts incurred by entity for provision of key management personnel services provided by separate management entities [text block] Basis of preparation Disclosure of basis of preparation of financial statements [text block] Capital structure [Abstract] Summary of capital structure Disclosure of classes of share capital [text block] Disclosure of classes of share capital [line items] Disclosure of classes of share capital [table] Commitments and contingencies Disclosure of commitments and contingent liabilities [text block] Maturity of commitments and contingencies Disclosure of contingent liabilities [text block] Financing obligation Disclosure of debt instruments [text block] Retirement benefit plan [Abstract] Disclosure of detailed information about borrowings [line items] Disclosure of detailed information about borrowings [table] Property, plant and equipment Disclosure of detailed information about property, plant and equipment [text block] Contract revenues [Abstract] Disclosure of disaggregation of revenue from contracts with customers [abstract] Disclosure of disaggregation of revenue from contracts with customers [line items] Disclosure of disaggregation of revenue from contracts with customers [table] Earnings per share Disclosure of earnings per share [text block] Retirement benefit plan Disclosure of employee benefits [text block] Subsequent events Expenses by category Disclosure of expenses [text block] Changes in defined benefit obligation, fair value of plan assets and unrecognized (gains) / losses Disclosure of fair value of plan assets [text block] Financial Result, net Cash and cash equivalents and financial assets [Abstract] Cash and cash equivalents and short-term financial assets Financial instruments and risk management Disclosure of financial risk management [text block] General and Administrative Disclosure of general and administrative expense [text block] Income taxes Weighted-average assumptions Disclosure of indirect measurement of fair value of goods or services received, share options granted during period [text block] Summary of significant accounting policies [Abstract] Right-of-use assets and lease liabilities Disclosure of maturity analysis of operating lease payments [line items] Disclosure of maturity analysis of operating lease payments [table] Financial instruments and risk management [Abstract] Disclosure of nature and extent of risks arising from financial instruments [line items] Disclosure of nature and extent of risks arising from financial instruments [table] Defined benefit pension plan amounts recognized in the balance sheet and statement of income Disclosure of net defined benefit liability (asset) [text block] Disclosure of net defined benefit liability (asset) [line items] Disclosure of net defined benefit liability (asset) [table] Subsequent events [Abstract] Disclosure of non-adjusting events after reporting period [line items] Disclosure of non-adjusting events after reporting period [table] Summary of non-vested share awards (restricted share and restricted share units) Disclosure of number and weighted average exercise prices of other equity instruments [text block] Number and weighted average exercise prices of options under share option programs Disclosure of number and weighted average exercise prices of share options [text block] Number and weighted average exercise prices of options under the share option programs [Abstract] Disclosure of number and weighted average remaining contractual life of outstanding share options [abstract] Outstanding options, exercise price range and expiry dates Disclosure of number and weighted average remaining contractual life of outstanding share options [text block] Disclosure of number and weighted average remaining contractual life of outstanding share options [line items] Disclosure of number and weighted average remaining contractual life of outstanding share options [table] Capital risk management [Abstract] Capital risk management Disclosure of objectives, policies and processes for managing capital [text block] Segment reporting [Abstract] Disclosure of operating segments [abstract] Property, plant and equipment [Abstract] Property, plant and equipment Disclosure of property, plant and equipment [text block] Disclosure of detailed information about property, plant and equipment [line items] Disclosure of detailed information about property, plant and equipment [table] Right-of-use assets and lease liabilities [Abstract] Disclosure of quantitative information about leases for lessee [abstract] Information about Right-of-Use Assets Disclosure of quantitative information about right-of-use assets [text block] Disclosure of quantitative information about right-of-use assets [line items] Disclosure of quantitative information about right-of-use assets [table] Disclosure of range of exercise prices of outstanding share options [line items] Disclosure of range of exercise prices of outstanding share options [table] Related-party transactions Disclosure of related party [text block] Research and Development Disclosure of research and development expense [text block] Cash and cash equivalents and financial assets Contract revenues Disclosure of revenue [text block] Contract Revenues Disclosure of revenue from contracts with customers [text block] Actuarial assumptions [Abstract] Disclosure of sensitivity analysis for actuarial assumptions [abstract] Actuarial assumptions and sensitivity analysis Disclosure of sensitivity analysis for actuarial assumptions [text block] Disclosure of sensitivity analysis for actuarial assumptions [line items] Disclosure of sensitivity analysis for actuarial assumptions [table] Share capital Disclosure of share capital, reserves and other equity interest [text block] Share-based compensation Disclosure of share-based payment arrangements [text block] Summary of significant accounting policies Disclosure of significant accounting policies [text block] Unrecognized deductible temporary differences, unused tax losses and unused tax credits [Abstract] Disclosure of temporary difference, unused tax losses and unused tax credits [abstract] Unrecognized deductible temporary differences, unused tax losses and unused tax credits Disclosure of temporary difference, unused tax losses and unused tax credits [text block] Disclosure of temporary difference, unused tax losses and unused tax credits [line items] Disclosure of temporary difference, unused tax losses and unused tax credits [table] Share-based compensation [Abstract] Share-based compensation plans outstanding Disclosure of terms and conditions of share-based payment arrangement [text block] Disclosure of terms and conditions of share-based payment arrangement [line items] Disclosure of terms and conditions of share-based payment arrangement [table] Trade payables and accrued liabilities Disclosure of trade and other payables [text block] Related-party transactions [Abstract] Disposals Disposals, property, plant and equipment Earnings/(loss) per share: Earnings per share [Abstract] Earnings per share Earnings per share [text block] Exchange gains on cash and cash equivalents Effect of exchange rate changes on cash and cash equivalents Entity's total for related parties [member] Total shareholders' equity Balance, beginning of period Balance, end of period Equity Shareholders' equity Total shareholders' equity and liabilities Equity and liabilities SHAREHOLDERS' EQUITY AND LIABILITIES Equity [Member] Exercise price (in USD per share) Dividend yield Expense charged against the income statement Expense from share-based payment transactions with employees Expense for short-term leases and leases of low value Expense relating to short-term leases for which recognition exemption has been used Changes in Contract Assets and Contract Liabilities Financial expense Finance costs Finance costs Finance costs paid, classified as operating activities Financial income Financial income Finance result, net Finance income (cost) Interest income Finance income received, classified as operating activities Financial assets Financial assets, category [member] Financial liabilities Financial liabilities, category [member] Furniture [Member] Remeasurement through other comprehensive loss Gain (loss) on remeasurement, net defined benefit liability (asset) Exchange differences Loss in finance results, net Acquisition Cost [Member] Statements of Income/(Loss) [Abstract] Income tax expense Effective income tax rate benefit/(expense) Income tax expense Net (decrease)/increase in cash and cash equivalents Net (decrease)/increase in cash and cash equivalents Increase (decrease) in cash and cash equivalents Increase in tax losses available as an offset Decrease/(increase) from actual defined benefit obligation Decrease/(increase) from actual defined benefit obligation Increase (decrease) in defined benefit obligation due to reasonably possible increase in actuarial assumption Net pension cost Increase (decrease) in net defined benefit liability (asset) Shares issued (in shares) Increase (decrease) in number of ordinary shares issued Conversion note agreement, net of transaction costs Conversion of note agreement, net of transaction costs Exercise of options Increase (decrease) through exercise of options, equity Share-based payments Increase (decrease) through share-based payment transactions, equity Issuance of shares to be held as treasury shares, net of transaction costs Held as treasury shares, net of transaction costs Net interest expense Interest expense Effective interest recorded to amortize the host debt Interest expense on lease liabilities Interest expense on lease liabilities Interest paid Interest paid, classified as operating activities Interest Rate [member] Interest rate risk [member] Share capital Issued capital Share Capital [Member] Issued capital [member] Total Key management personnel compensation Post-employment benefits Share-based compensation Short-term employee benefits Executives and Directors [Member] More Than 5 Years [Member] Loss Expiry, December 31, 2024 [Member] Later than four years and not later than five years [member] Between 1 and 3 Years [Member] Between 1 and 3 Years [Member] Loss Expiry, December 31, 2021 [Member] Later than one year and not later than two years [member] Between 3 and 5 Years [Member] Loss Expiry, December 31, 2023 [Member] Later than three years and not later than four years [member] Between 3 and 5 Years [Member] Loss Expiry, December 31, 2022 [Member] Later than two years and not later than three years [member] Long-term Lease Liabilities [Member] Lease liabilities [member] Leasehold Improvements [Member] Total liabilities Liabilities Potential defined benefit obligation Net defined benefit liabilities, end of period Net defined benefit liabilities, beginning of period Defined benefit obligation, beginning of period Defined benefit obligation, end of period Net defined benefit liability (asset) Liquidity Risk [Member] Liquidity risk [member] Income taxes [Abstract] Income taxes [Abstract] Maturity [axis] Net defined benefit liability (asset) [axis] Net defined benefit liability (asset) [member] Non-adjusting events after reporting period [axis] Non-adjusting events after reporting period [member] Total non-current assets Non-current assets Non-current assets Non-current assets [abstract] Long-term lease liabilities Non-current lease liabilities Total non-current liabilities Non-current liabilities Non-current liabilities Non-current liabilities [abstract] Net employee defined benefit liabilities Non-current provisions for employee benefits Long-term financial assets Deposits in escrow accounts Within 1 Year [Member] Loss Expiry, December 31, 2020 [Member] 2019 [Member] Granted during the year (in shares) Number of non-vested share awards granted (in shares) Number of other equity instruments granted in share-based payment arrangement Vested and exercisable (in shares) Number of other equity instruments exercisable in share-based payment arrangement Vested during the year Number of other equity instruments exercised or vested in share-based payment arrangement Expired during the year (in shares) Number of other equity instruments expired in share-based payment arrangement Forfeited during the year (in shares) Number of other equity instruments forfeited in share-based payment arrangement Non-vested at beginning of period (in shares) Non-vested at end of period (in shares) Number of other equity instruments outstanding in share-based payment arrangement Outstanding Options (in shares) Outstanding at end of period (in shares) Outstanding at beginning of period (in shares) Exercisable (in shares) Number of share options exercisable in share-based payment arrangement Exercised during the year (in shares) Number of share options exercised in share-based payment arrangement Expired during the year (in shares) Number of share options expired in share-based payment arrangement Forfeited during the year (in shares) Number of share options forfeited in share-based payment arrangement Number of options awarded (in shares) Granted during the year (in shares) Number of additional authorized shares (in shares) Number of shares authorised Number of common shares sold (in shares) Number of shares issued Issuance of shares: Shares outstanding, excluding treasury shares (in shares) Number of shares outstanding Office Equipment [Member] Office equipment [member] Total operating expenses Operating expense Common Shares [Member] Ordinary shares [member] Other comprehensive income/(loss) Other comprehensive income Remeasurement income/(losses) on defined benefit plans (net of tax) Other comprehensive income, net of tax, gains (losses) on remeasurements of defined benefit plans Other accrued expenses Other current liabilities Interest rate on retirement savings capital Other material actuarial assumptions Interest Rate on Savings Capital [Member] Other material actuarial assumptions [member] Other operating income/(expense) Nominal value per share (in CHF per share) Par value per share Net pension cost through statement of income Past service cost and gains (losses) arising from settlements, net defined benefit liability (asset) Transaction costs on issuance of shares Payments for share issue costs Benefits deposited Benefits deposited Payments from plan, net defined benefit liability (asset) Principal payments of lease obligations Payments of lease liabilities, classified as financing activities Payment for the issuance of treasury shares Payments to acquire or redeem entity's shares Percentage of contract revenues Percentage of entity's revenue Percentage decrease in actuarial assumption Percentage of reasonably possible decrease in actuarial assumption Percentage increase in actuarial assumption Percentage of reasonably possible increase in actuarial assumption Performance obligations [axis] Performance obligations [member] Fair value of plan assets Fair value of plan assets, end of period Fair value of plan assets, beginning of period Plan assets, at fair value Fair Value of Plan Assets [Member] Plan assets [member] Expected contribution by employer to be paid to post-retirement benefit plans Prepaid expenses and accrued income [Abstract] Defined Benefit Obligation [Member] Present value of defined benefit obligation [member] Right-of-use assets and lease liabilities [Abstract] Proceeds from long-term financing obligation Proceeds from issuance of common shares - option plan Proceeds from exercise of options Gross proceeds received Proceeds from issue of ordinary shares Proceeds from issuance of treasury shares, net of transaction costs Proceeds from sale of property, plant and equipment Proceeds from sales of property, plant and equipment, classified as investing activities Products and services [axis] Products and services [member] Income/(loss) for the period Income/(loss) for the period Net income/(loss) for the period Net income/(loss) attributable to equity holders of the Company Numerator [Abstract] Profit (loss), attributable to ordinary equity holders of parent entity [abstract] Income/(loss) before tax Income/(loss) before income tax Operating income/(loss) Profit (loss) from operating activities Property, plant and equipment Property, plant and equipment, beginning of period Property, plant and equipment, end of period Property, plant and equipment [member] Commitments Provisions Short-term financial assets Purchase of financial instruments, classified as investing activities Purchases of property, plant and equipment Purchase of property, plant and equipment, classified as investing activities Range [axis] Ranges [member] Ranges of exercise prices for outstanding share options [axis] Ranges of exercise prices for outstanding share options [member] Milestone payment receivable Eligible grant amount receivable Receivables from contracts with customers Income tax expense reconciled to Income / (loss) [Abstract] Reconciliation of accounting profit multiplied by applicable tax rates [abstract] Property, plant and equipment [Abstract] Reconciliation of changes in property, plant and equipment [abstract] Repayment of short-term financing obligation Repayments of current borrowings Research & development expenses Total research and development expenses Research and development expense Accumulated losses Retained earnings Accumulated Losses [Member] Retained earnings [member] Return on plan assets excluding interest income Return on plan assets excluding interest income Total revenue Revenue Revenues Contract revenues [Abstract] Contract revenue Total contract revenue Recognized revenues Performance obligations satisfied in previous periods Amounts included in the contract liability at the beginning of the period Right-of-use assets Balance, end of period Balance, beginning of period General & administrative expenses Total general and administrative expenses Selling, general and administrative expense General and administrative [Abstract] Selling, general and administrative expense [abstract] Transaction offering costs Issuance costs Share issue related cost Share premium Share Premium [Member] Share-based payment arrangements [member] Short-term Financing Obligation [Member] Accrual of performance-related remuneration Short-term employee benefits accruals Statements of Cash Flows [Abstract] Statements of Changes in Equity [Abstract] Statement of changes in equity [line items] Statement of changes in equity [table] Statements of Comprehensive Income/(Loss) [Abstract] Balance Sheets [Abstract] Total liability Surplus (deficit) in plan Defined benefit pension plan amount recognized in balance sheet [Abstract] Surplus (deficit) in plan [abstract] Income not subject to tax/(expenses) not deductible for tax purposes Tax effect of expense not deductible in determining taxable profit (tax loss) Income not subject to tax/(expenses) not deductible for tax purposes Tax effect of revenues exempt from taxation Effect of unused tax losses and tax offsets not recognized as deferred tax assets Tax effect of tax losses Tax expense/(benefit) calculated at the statutory rate of 13.6% (13.6% for 2019 and 20.6% for 2018) Temporary difference, unused tax losses and unused tax credits [axis] Temporary difference, unused tax losses and unused tax credits [member] Top of Range [Member] Top of range [member] Trade and other payables Total trade and other payables Trade and other current payables Trade payables and accrued liabilities [Abstract] Other current receivables [abstract] Trade and other receivables [abstract] Total potential collaboration agreement value remaining Expected transaction price allocation Transaction price allocated to remaining performance obligations Treasury shares Treasury shares Treasury Shares [Member] Treasury shares [member] Types of contracts [axis] Types of contracts [member] Types of risks [axis] Risks [member] Types of share-based payment arrangements [axis] Unused tax losses Unused tax losses for which no deferred tax asset recognised Tax Losses [Member] Unused tax losses [member] Estimated useful life Useful life measured as period of time, property, plant and equipment Weighted average duration period for defined benefit obligation Vested and exercisable (in CHF per share) Weighted average exercise price of other equity instruments exercisable in share-based payment arrangement Vested during the year (in CHF per share) Weighted average exercise price of other equity instruments exercised or vested in share-based payment arrangement Expired during the year (in CHF per share) Weighted average exercise price of other equity instruments expired in share-based payment arrangement Forfeited during the year (in CHF per share) Weighted average exercise price of other equity instruments forfeited in share-based payment arrangement Granted during the year (in CHF per share) Weighted average fair value, restricted share awards granted (in CHF per share) Weighted average exercise price of other equity instruments granted in share-based payment arrangement Non-vested at beginning of period (in CHF per share) Non-vested at end of period (in CHF per share) Weighted average exercise price of other equity instruments outstanding in share-based payment arrangement Exercisable (in CHF per share) Weighted average exercise price of share options exercisable in share-based payment arrangement Exercised during the year (in CHF per share) Expired during the year (in CHF per share) Forfeited during the year (in CHF per share) Weighted average exercise price for options granted (in CHF/USD per share) Granted during the year (in CHF per share) Weighted average share price of common share options exercised (in dollars per share) Weighted average share price for share options in share-based payment arrangement exercised during period at date of exercise Outstanding at beginning of period (in CHF per share) Outstanding at end of period (in CHF per share) Weighted average exercise price of share options outstanding in share-based payment arrangement Weighted average incremental borrowing rate Weighted average lessee's incremental borrowing rate applied to lease liabilities recognised at date of initial application of IFRS 16 Weighted average remaining term (years) Weighted average remaining contractual life of outstanding share options Share price, weighted average (in USD per share) Weighted average share price Weighted average fair value, options granted (in USD/CHF per share) Weighted average share price, share options granted Weighted-average number of shares outstanding to equity holders (in shares) Weighted average number of ordinary shares outstanding Denominator [Abstract] Weighted average ordinary shares and adjusted weighted average ordinary shares [abstract] Cover [Abstract] Amendment Flag Entity Address, Country Current Fiscal Year End Date Document Period End Date Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Current Reporting Status Entity Filer Category Entity Registrant Name Entity Central Index Key Entity Common Stock, Shares Outstanding Document Fiscal Year Focus Document Fiscal Period Focus Document Type Document Annual Report Document Transition Report Document Shell Company Report Document Accounting Standard Entity Interactive Data Current Entity Shell Company Entity Emerging Growth Company Entity Ex Transition Period CHF [Member] Switzerland, Francs EUR [Member] Euro Member Countries, Euro USD [Member] United States of America, Dollars All Currencies [Domain] Currency [Axis] The amount of current other receivables and receivables from value added taxes and withholding taxes. Current receivables classified as other and value added and withholding taxes Other current receivables Total Expenses, Operating [Abstract] Operating expenses The gain (loss) arising from the change in fair value of a convertible instrument. Gain (loss) arising from change in fair value of convertible instrument Change in fair value of conversion feature The cash inflow from issuing ordinary shares net of underwriting fees. Proceeds from issuing shares, net of underwriting fees Proceeds from public offerings, net of underwriting fees Proceeds from public offerings of common shares, net of underwriting fees The increase in equity through the issue of restricted share awards. Issue of Equity, Restricted Share Awards Restricted share awards The cash outflow for deposit of rent. Cash Advances for Rent Deposit Rental deposits The cash outflow for share issue costs for public offerings. Payments for share issue costs on public offering Transaction costs on public offerings of common shares The cash inflow from the issuing of convertible debt. Proceeds from issue of convertible debt Proceeds from issuance of convertible loan Changes in working capital [Abstract] Changes in working capital: Adjustments for increase (decrease) in long-term financial liabilities to reconcile profit (loss) to net cash flow from (used in) operating activities. Adjustments for Increase (Decrease) Long-term Financial Liabilities Decrease in financing obligation Adjustments for decrease (increase) in accrued income to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Profit (loss)] Adjustments for decrease (increase) in accrued income (Increase)/decrease in accrued income Adjustments for increase (decrease) in accrued expenses to reconcile profit (loss) to net cash flow from (used in) operating activities. Adjustments for increase (decrease) in accrued expenses (Decrease)/increase in accrued expenses Adjustments for decrease (increase) in prepaid expenses to reconcile profit (loss) to net cash flow from (used in) operating activities. Adjustments for decrease (increase) in prepaid expense (Increase) in prepaid expenses Adjustments for depreciation expense for right-of-use assets to reconcile profit (loss) to net cash flow from (used in) operating activities. Adjustments for depreciation expense, right-of-use assets Depreciation of right-of-use assets The disclosure of prepayments and accrued income. Disclosure of prepaid expenses and accrued income [Text Block] Prepaid expenses and accrued income Schedule disclosing information related to details of Prepaid expenses and accrued income. Prepaid Expenses and Accrued Income [Table] Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. Prepaid Expenses and Accrued Income [Line Items] Percentage that represents the percentage of total accrued income. Percentage of Accrued Income Percentage of accrued income The 2014 contractual research agreement associated with collaboration with Janssen Pharmaceuticals. Collaboration agreement of 2014, Janssen Pharmaceuticals [Member] Janssen [Member] 2014 Agreement with Janssen Pharmaceuticals [Member] Sensitivity analysis, actuarial assumptions [Abstract] Sensitivity analysis [Abstract] Published actuarial tables that detail assumptions about mortality and disability rates which are used to determine benefit obligations for defined benefit plans. Issued Actuarial Tables, Switzerland Mortality and disability rates The reasonably possible percentage of the increase in the actuarial assumption used to determine the present value of defined benefit obligation. Percentage of reasonably possible increase in actuarial assumption [Member] +0.5% Increase [Member] The reasonably possible percentage of the decrease in the actuarial assumption used to determine the present value of defined benefit obligation. Percentage of reasonably possible decrease in actuarial assumption [Member] -0.5% Decrease [Member] This member stands for defined benefit plans change in other comprehensive loss. Change in other comprehensive loss, defined benefit plan [Member] Change in Other Comprehensive Loss [Member] Change in other comprehensive loss [Abstract] Change in other comprehensive loss [Abstract] The amount of gain (loss) for the (increase) decrease in value of benefit obligation for the change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. Other comprehensive income (loss}, defined benefit plan, gain (loss) Other comprehensive loss, beginning of period Other comprehensive loss, end of period Number of equity-based instrument plans approved by the entity. Number of Equity-based Instrument Plans Number of equity-based instrument plans Share-based plans outstanding [Abstract] Share-based plans outstanding [Abstract] For vesting requirements for a type of share-based payment arrangement that existed at any time during the period, this element represents the period which an employees' right to exercise an award is no longer contingent on satisfaction of a service condition. Vesting requirements for share-based payment arrangement, award vesting period Vesting conditions Vesting conditions A share-based payment arrangement that existed at any time during the reporting period. Stock option plan B [Member] Stock Option Plan B [Member] The 2016 Plan authorizes the grant of incentive and non-qualified share options, share appreciation rights, restricted share awards, restricted share units, unrestricted share awards, performance share awards, performance-based awards to covered employees and dividend equivalent rights. 2016 Share Option and Incentive Plan [Member] 2016 SOIP [Member] A share-based payment arrangement that existed at any time during the reporting period. Stock option plan C1 [Member] Stock Option Plan C1 [Member] Refers to personnel employed by the entity. Employees [Member] The maximum term of options granted for a type of share-based payment arrangement that existed at any time during the period. Maximum term of options granted for share-based payment arrangement Contractual life of options A share-based payment arrangement that existed at any time during the reporting period. Stock option plan A [Member] Stock Option Plan A [Member] Vesting tranche one of the 2016 Plan authorizes the grant of incentive and non-qualified share options, share appreciation rights, restricted share awards, restricted share units, unrestricted share awards, performance share awards, performance-based awards to covered employees and dividend equivalent rights. 2016 Share Option and Incentive Plan, Vesting Tranche One [Member] 2016 SOIP, Vesting Condition 1 [Member] Vesting tranche two of the 2016 Plan authorizes the grant of incentive and non-qualified share options, share appreciation rights, restricted share awards, restricted share units, unrestricted share awards, performance share awards, performance-based awards to covered employees and dividend equivalent rights. 2016 Share Option and Incentive Plan, Vesting Tranche Two [Member] 2016 SOIP, Vesting Condition 2 [Member] Vesting tranche three of the 2016 Plan authorizes the grant of incentive and non-qualified share options, share appreciation rights, restricted share awards, restricted share units, unrestricted share awards, performance share awards, performance-based awards to covered employees and dividend equivalent rights. 2016 Share Option and Incentive Plan, Vesting Tranche Three [Member] 2016 SOIP, Vesting Condition 3 [Member] Other current receivables [Abstract] The disclosure of other current receivables. Disclosure of other current receivables [Text Block] Other current receivables The disclosure of detailed information about the useful life of property, plant and equipment. Schedule of information about property, plant and equipment useful life [Table Text Block] Estimated useful life The disclosure of detailed information about the estimated lease term by right-of-use asset by category. Schedule of information about contract lease term by right-of-use asset categories [Table Text Block] Estimated Lease Term by Right-of-use Asset Categories Property plant and equipment estimated useful life [Abstract] Estimated useful life [Abstract] This member stands for a class of property, plant and equipment representing laboratory equipment. Laboratory equipment [Member] Laboratory Equipment [Member] This member stands for a class of property, plant and equipment representing improvements to assets held under a lease agreement and fixtures and fittings that are not permanently attached to real property. Leasehold improvements and fixtures and fittings [Member] Leasehold Improvements/Furniture [Member] Impact on statements of income/(loss) and cash flows [Abstract] Impact on statements of income/(loss) and cash flows [Abstract] Contractual undiscounted cash flows for lease liabilities [Abstract] Contractual undiscounted cash flows for lease liabilities [Abstract] The amount of undiscounted operating lease payments due for lease liabilities. Undiscounted operating lease payments due Contractual undiscounted cash flows for lease liabilities The expense for leases recognized through profit and loss. Expense relating to leases Total Right-of-use leased assets [Abstract] Right-of-use of leased assets [Abstract] The amount of decrease in right-of-use assets from disposals. Disposal of right-of-use assets Disposals Key managers, or ranking officers of an entity, appointed to their position by the board of directors. Executive Management [Member] Executives [Member] This member stands for 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. Restricted Shares and Restricted Share Units [Member] Non-vested Share Awards [Member] This member stands for equity instruments that are convertible to stock after a specified period of time. Restricted Stock Units [Member] Restricted Stock Units [Member] Key managers of an entity who collectively have responsibility of governing the entity. Board of Directors [Member] Directors [Member] This member stands for equity instruments that are prohibited for sale for a specified period of time. Restricted shares [Member] Restricted Share Awards [Member] Number Of Non-vested Shares [Abstract] Number of non-vested shares [Abstract] The number of other equity instruments (ie other than share options) exercised in a share-based payment arrangement. Number of other equity instruments exercised in share-based payment arrangement Exercised during the year (in shares) Weighted Average Exercise Price [Abstract] Weighted Average grant date fair value [Abstract] Weighted average exercise price [Abstract] The weighted average exercise price of other equity instruments (ie other than share options) exercised in a share-based payment arrangement. [Refer: Weighted average [member]] Weighted average exercise price of other equity instruments exercised in sharebased payment arrangement2019 Exercised during the year (in CHF per share) Share-based payment arrangement [Abstract] Share-based compensation [Abstract] The maximum term of other equity instruments (ie other than share options) granted for a type of share-based payment arrangement that existed at any time during the period. Maximum Term Of Other Equity Instruments Granted For Share Based Payment Arrangement Contractual life of non-vested share awards The weighted average exercise price of non-vested other equity instruments (ie other than share options) granted in a share-based payment arrangement. Weighted average exercise price of non-vested other equity instruments granted in share-based payment arrangement Weighted average fair value, non-vested restricted share awards granted (in CHF per share) Weighted Average Assumptions [Abstract] Weighted average assumptions [Abstract] An former executive officer responsible for overseeing the financial activities of the entity. Former Chief Executive Financial Officer [Member] Former Chief Financial Officer [Member] The estimated lease term, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Estimated lease term Estimated lease term Schedule of cash and cash equivalent balances, including foreign currencies in which the balances are denominated. Cash and cash equivalents [Table] Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. Cash and cash equivalent [Line Items] The disclosure of detailed information about other current receivables. Disclosure of detailed information about other current receivables [Table Text Block] Other current receivables Commitments and contingencies [Abstract] Outstanding Options Exercise Price Range and Expiry Dates [Abstract] Outstanding options, exercise price range and expiry dates [Abstract] The date on which share options will expired. Share Options Date of Expiry Expiration Dates This member stands for exercise of price range two. Range Of Exercise Prices Two [Member] CHF 9.53 [Member] This member stands for exercise of price range three Range Of Exercise Prices Three [Member] USD 5.04 to USD 12.30 [Member] This member stands for exercise of price range one. Range of Exercise Prices one [Member] CHF 0.15 [Member] The amount of current accrued research and development costs. Current accrued research and development costs Accrued research and development costs Schedule disclosing information related to other current receivables. Disclosure of other current receivables [Table] Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. Disclosure of other current receivables [Line Items] Refers to the maturity period over which the entity considers carrying value of current receivables to correspond to their fair value. Period of maturity, receivables fair value carrying amount Maturity period of assets The number of escrow accounts with cash deposits of the entity. Number of escrow deposit accounts Number of deposits in escrow accounts The disclosure of detailed information about prepaid expenses and accrued income. Disclosure of detailed information about prepaid expenses and accrued income [Table Text Block] Prepaid expenses and accrued income Basis of preparation [Abstract] Schedule disclosing information related to the entity's ability to continue as a going concern. Disclosure of going concern [Table] Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. Disclosure of classes of going concern [Line Items] This member represents the equity instruments that are the first or initial sale of equity shares by a private company to the public. Initial Public Offering [Member] Public Offering [Member] Going Concern [Abstract] Going concern [Abstract] Payment(s) received for milestone payments associated with a collaborative agreement. Collaborative agreement, Milestone payment received Milestone payment received The number of public offerings issued or completed by the entity. Number of Public Offerings Number of public offerings Contractual arrangement that involves two or more parties that both: (i) actively participate in a joint operating activity and (ii) are exposed to significant risks and rewards that depend on the commercial success of the joint operating activity. Collaboration and License Revenue Agreements [Member] Collaboration and License Revenue [Member] The collaboration agreement with Lilly for research and development. Collaboration Agreement with Lilly [Member] 2018 License Agreement with Eli Lilly and Company [Member] Lilly [Member] The description of the entity's accounting policy for grant income. Grant income [Policy Text Block] Grant income The description of the entity's accounting policy for the basis for how the entity classifies assets and liabilities as current and non-current. Description of accounting policy for classification of assets and liabilities [Policy Text Block] Current vs. non-current classification The description of the entity's accounting policy for judgments that management has made in the process of applying the entity's accounting policies that have the most significant effect on amounts recognized in the financial statements along with information about the assumptions that the entity makes about the future, and other major sources of estimation uncertainty at the end of the reporting period, that have a significant risk of resulting in a material adjustment to the carrying amounts of assets and liabilities within the next year. Description of accounting policy for accounting judgments and estimates [Policy Text Block] Critical judgments and accounting estimates The description of the entity's accounting policy for fair value of financial assets and liabilities. Fair value of financial assets and liabilities [Policy Text Block] Fair value of financial assets and liabilities The description of the entity's accounting policy for changes to accounting policies recently adopted by the entity. Disclosure Of Accounting Policy For Changes In Accounting Policies Recently Adopted [Text Block] Accounting policies, new standards, interpretations and amendments adopted by the Company The decrease in the net defined benefit liability (asset) resulting from interest costs resulting from the passage of time. Interest cost, net defined benefit liability (asset) Interest cost Interest cost General information [Abstract] The entire disclosure for general information about the entity. Disclosure of general information about the entity explanatory [Text Block] General information The number of unique proprietary platform technologies to discover, design and develop medicines and diagnostics to target misfolded proteins. Number of technology platforms Number of proprietary technology platforms An "at-the-market" offering is an offering of securities into an existing trading market for outstanding shares of the same class at other than a fixed price on, or through the facilities of, a national securities exchange, or to or through a market maker otherwise than on an exchange. At the Market Equity Offering [Member] ATM Program [Member] At the Market Equity Offering [Member] Convertible Note Agreement and Follow-On Offerings [Abstract] Convertible Note Agreement and Follow-On Offerings [Abstract] Price per share received for common stock issued or sold in public offering. Share issued price per share Share price (in dollars per share) The number of offerings of subscription rights by the entity. Number of offerings The amount of common shares authorized for sale in the open market. Common shares authorized for issuance sales in in open market Shares authorized for sale The carrying amount of debt identified as being convertible into another form of financial instrument. Convertible borrowings Convertible note agreement The increase in the number of ordinary shares issued under a convertible debt arrangement upon conversion of the debt. Increase in number of ordinary shares issued under conversion of convertible debt Shares issued to settle Convertible Note Agreement (in shares) Conversion of note agreement, net of transaction costs (in shares) The cash inflow from the issuing of ordinary shares net of costs to issue shares. Proceeds from issue of ordinary shares, net issuance costs Net proceeds Proceeds from issuance of ordinary shares, net of agent commissions This member represents the equity instruments that are included in each offering of equity shares by a private company to the public subsequent to the initial offering. Follow-on Offerings [Member] Follow-on Offerings [Member] This member represents the equity instruments that are the follow-on offering of equity shares by a private company to the public this issuance is after first follow-on offering. Second Subscription Rights [Member] This member represents the equity instruments from the right of the underwriter to sell additional equity shares over the initial allotment. Option for Over-Allotment [Member] Over-Allotment [Member] This member represents the equity instruments that are the follow-on offering of first equity shares by a private company to the public. First Subscription Rights [Member] First Subscription Rights [Member] Schedule disclosing information related to the Statement of Cash Flows. Statement of Cash Flows [Table] The member represents to convertible note agreement. Convertible Note Agreement [Member] Convertible Note Agreement with Lilly [Member] Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. Statement of Cash Flows [Line Items] Supplementary non-cash activity [Abstract] Supplementary non-cash activity includes the following: The gross value of the settlement of convertible debt that is settled via shares of entity's common shares. Repayment of convertible debt, Equity Settlement, Amount Settlement of convertible loan Amount of property plant and equipment acquired through noncash investing activities. Purchase of property, plant and equipment, classified as noncash investing activities Acquisition of property, plant and equipment Percentage of increase (decrease) in plan assets of defined benefit plan. Increase (decrease) in plan assets of defined benefit plan, percentage Percentage increase in plan assets The contributions paid to the plan are computed as a percentage of salary, adjusted for the age of the employee. Defined benefit plan, percentage of contribution Contributions paid to the plan by computing percentage in salary Amount of increase (decrease) in plan assets of defined benefit plan. Increase (decrease) in plan assets of defined benefit plan, amount Increase in plan assets This member stands for the employee portion of a domestic defined benefit plan. Defined benefits plan, Employee [Member] Employee [Member] Net pension cost in statement of income [Abstract] Net pension cost in statement of income [Abstract] The increase in the net defined benefit liability (asset) resulting from the passage of time. Interest income, net defined benefit liability (asset) Interest income Interest income This member stands for the employee portion of a domestic defined benefit plan. Defined benefits plan, Employer [Member] Employer [Member] Expenses by category [Abstract] Weighted Average Remaining [Abstract] Weighted average remaining term (years) [Abstract] The weighted average remaining contractual life of exercisable share options. Weighted average remaining contractual life of exercisable share options Exercisable Number of Options [Abstract] Number of options [Abstract] Financial Result, net [Abstract] Financial result, net [Abstract] Research and Development Expenses [Abstract] Research and Development [Abstract] The amount of all operating expenses allocated to research and development expenses. Research and development expense allocation, operating expense Operating expenses A class of employee benefits expense that represents wages and salaries that are allocated to research and development expenses. [Refer: Employee benefits expense] Research and development expense allocation, wages and salaries Payroll expenses Number of employees calculated on full-time equivalents within research and development. Employee, full-time equivalents in research and development Full-time equivalents in research and development A class of employee benefits expense that represents wages and salaries that are allocated to general and administrative expense. [Refer: Employee benefits expense] General and administrative expense allocation, wages and salaries Payroll expenses The amount of all operating expenses allocated to general and administrative expenses. General and administrative expense allocation, operating expense Operating expenses The amount of expense from share-based payment transactions with employees allocated to general and administrative expense. General and administrative expense allocation, expense from share-based payment transactions with employees Share-based compensation Number of employees calculated on full-time equivalents within general and administrative expenses. Employee, full-time equivalents in general and administrative expenses Full-time equivalents in general and administrative functions The amount of expense from share-based payment transactions with employees that are allocated to research and development expenses. Research and development expense allocation, expense from share-based payment transactions with employees Share-based compensation Schedule of disclosing information related to commitments and contingencies. Disclosure of information about commitments and contingencies [Table] Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. Disclosure of information about commitments and contingencies [Line Items] Commitments [Abstract] Commitments and contingencies [Abstract] The period of time required by the lessee in a lease agreement to provide notice of cancellation of a lease to the lessor. Rental contract, period for notice of cancellation Notice period for cancellation of rental contract The amount of provisions for research and development contracts with external providers. Provisions, research contracts External research projects Tax losses split by expiry date [Abstract] Tax losses split by expiry date [Abstract] This member stands for a time band of later than six years and not later than seven years. Later than six years and not later than seven years [Member] Loss Expiry, December 31, 2026 [Member] This member stands for a time band not later than prior year end. Not later than prior year end [Member] Loss Expiry, December 31, 2019 [Member] This member stands for a time band of later than seven years and not later than eight years. Later Than Six Years And Not Later Than Eight Years [Member] Loss Expiry, December 31, 2027 [Member] This member stands for tax credits that have been received and are carried forward for use against future taxable profit related to the retirement benefit plan. Unused tax credits, Retirement benefit plan [Member] Deductible Temporary Differences Related to Retirement Benefit Plan [Member] This member stands for tax credits that have been received and are carried forward for use against future taxable profit related to right-of-use assets and lease liabilities. Unused tax credits, Right-of-use assets and lease liabilities net [Member] Deductible Temporary Differences Related to Right-of-use Assets and Lease Liabilities [Member] This member stands for a time band of later than five years and not later than six years. Later than five years and not later than six years [Member] Loss Expiry, December 31, 2025 [Member] Changes in fair value of plan assets [Abstract] Changes in fair value of plan assets [Abstract] Shelf Registration Statement [Abstract] The number of future offerings of securities the entity may execute covered by the Shelf Registration Statement. Number of future offerings of securities authorized under Shelf Registration Statement Number of additional future public offerings The potential additional cash inflow from issuing equity instruments through a Shelf Registration Statement. Potential additional proceeds, sale of equity instruments, Shelf Registration Statement Additional proceeds from Shelf Registration Statement The number of common stock, debt securities, warrants, purchase contracts, units, subscription rights or any combination of the foregoing in one or more future public offerings authorized for sale by the entity through a Shelf Registration Statement. Shelf Registration Statement, shares authorized Shares authorized under Shelf Registration Statement (in shares) The increase in equity resulting from the issue of shares under incentive plans. Increase through shares issued under incentive plans Issuance of shares - incentive plans The increase (decrease) in equity shares resulting from treasury share transactions. Increase (decrease) through treasury share transactions, equity, shares Issuance of shares to be held as treasury shares, net of transaction costs (in shares) The increase in the number of ordinary shares issued under incentive plans. Increase in number of ordinary shares issued under incentive plans Issuance of shares - incentive plans (in shares) The increase in equity resulting from the issue of shares under share-based payment arrangements equity instruments other that share options net of expirations and forfeitures. Increase through shares issued, share-based payment arrangement, other equity instruments net of expiration and forfeiture Issuance of shares - incentive plans, net of RSU expiration and forfeiture The number of shares that have been authorized and issued, including treasury shares held. [Refer: Treasury shares] Number of shares outstanding including treasury shares Balance, beginning of period (in shares) Balance, end of period (in shares) The number of other equity instruments (ie other than share options) expired or forfeited in a share-based payment arrangement. Number of other equity instruments expired or forfeited in share-based payment arrangement Number of RSUs either expired or forfeited (in shares) The increase in number of equity instruments issued resulting from the issue of shares under share-based payment arrangements equity instruments other that share options net of expirations and forfeitures. Increase in number of shares issued, share-based payment arrangement, other equity instruments net of expiration and forfeiture Issuance of shares - incentive plans, net of RSU expiration and forfeiture (in shares) Tabular disclosure of information related to the contractual undiscounted cash flows. Schedule of contractual undiscounted cash flows [Table Text Block] Contractual Undiscounted Cash Flows The disclosure of right-of-use assets impact on the company's statements of income/(loss) and statements of cash flows. Disclosure of right-of-use assets impact on statements [Text Block] Impact on Statements of income/(loss) and Statements of Cash Flows The disclosure of detailed information about trade payables and accrued liabilities. Disclosure of detailed information about trade payables and accrued liabilities [Table Text Block] Trade payables and accrued liabilities Financing obligation [Abstract] The increase in contract liabilities for the period. Contract liabilities, addition Deferred income, additions The decrease in contract assets for the period. Contract assets, deductions Accrued income, deductions The increase in contract assets for the period. Contract assets, additions Accrued income, additions The decrease in contract liabilities for the period. Contract liabilities, deductions Deferred income, deductions The number of the entity's common shares sold to a related party in related party transactions. Number of common shares sold, related party transactions Number of shares purchased under subscription rights offering by related party (in shares) The number of persons that are the included in Board of Directors excluding the Chief Executive Officer. Number of persons, key management, Board of Directors Number of individuals, Board of Directors The number of persons that comprise key management of the entity that are Executive Management. Number of persons, key management, Executive Management Number of individuals, Executive Management The disclosure of detailed information about the expiration of income tax losses that may be carried forward. Disclosure of detailed information about income tax losses expiry [Table Text Block] Tax losses expiry dates The disclosure of detailed information about income tax reconciliation. Disclosure of detailed information about income tax reconciliation [Table Text Block] Income tax expense reconciled to loss The amount of revenue reclassified to other income (expense). Revenue reclassified to other income (expense) Amount reclassified from contract revenue to other income/(expense) Contract Revenue [Abstract] Contract Revenue [Abstract] The 2014 contractual research agreement associated with collaboration with Life Molecular Imaging. License and collaboration agreement of 2014, Life Molecular Imaging [Member] Life Molecular Imaging [Member] 2014 Agreement with Life Molecular Imaging (formerly Piramal Imaging SA) Imaging [Member] The 2012 contractual research agreement associated with collaboration with Genentech. Collaboration agreement of 2012, Genentech [Member] Genentech [Member] 2012 Agreement with Genentech [Member] The 2016 contractual research agreement associated with collaboration with Biogen. Collaboration agreement of 2016, Biogen [Member] Biogen [Member] 2016 Agreement with Biogen [Member] contractual research agreement associated with collaboration with other. Other agreement [Member] Other [Member] The amount of consideration recognized for the milestone payment(s) associated with a collaborative agreement during the period. Collaborative Agreement, Milestone Payment Recognized Milestone payment recognized The cumulative payments received related to revenue from upfront license fees, milestone payments and revenue from research agreements associated with a collaborative agreement. Collaborative agreement, Cumulative payments received Cumulative payments received Period of time that notice is required to be given for cancellation of the collaborative agreement contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Collaborative agreement, Notice of contract termination period Period to provide notice of termination of agreement The research and development of medicines for the treatment of Alzheimer's disease. Anti-tau antibody in AD [Member] Anti-tau Antibody in AD [Member] Number of times payment(s) received for milestone payments associated with a collaborative agreement. Number of milestone payments received Number of milestone payments received The total potential value of the collaborative agreement. Collaborative agreement, potential value Total potential collaboration agreement value Performance obligation related to right-of-use license. Right-of-use license [Member] Right-of-use License [Member] Refers to a milestone payment arrangement related to certain commercial milestones. Milestone payments, commercial [Member] Commercial [Member] The number of installments for satisfying a milestone payment associated with a collaborative agreement. Collaborative agreement, milestone payment, number of installments Number of installments The number of representatives in a joint steering committee by each party as per the agreement. Number of representatives in joint steering committee by each party Number of representatives in joint steering committee by each party Performance obligation related to a phase 2 clinical study of a licensed product. Phase two clinical study, licensed product [Member] Phase 2 Clinical Study Licensed Product [Member] Refers to a milestone payment arrangement related to clinical and regulatory milestones. Milestone payments, clinical and regulatory milestones [Member] Clinical and Regulatory [Member] The research and development of medicines for the treatment of Alzheimer's disease and other neurodegenerative diseases. Tau Morphomer Small Molecule [Member] Morphomer Tau small molecule [Member] Performance obligation related to research and development. Research and development [Member] Research and Development [Member] The first amendment to the collaboration agreement with Lilly for research and development. Collaboration Agreement with Lilly, First Amendment [Member] 2018 License Agreement with Eli Lilly, First Amendment [Member] The second amendment to the collaboration agreement with Lilly for research and development. Collaboration Agreement with Lilly, Second Amendment [Member] 2018 License Agreement with Eli Lilly, Second Amendment [Member] The research and development of medicines for the treatment of Alzheimer's disease. Alpha-synuclein and TDP-43 PET tracer in AD [Member] A-syn and TDP-43 PET tracers - 2016 agreement with Biogen [Member] The number of performance obligations identified applicable to the entity's assessment of a specific contractual arrangement. Number of performance obligations identified Number of performance obligations identified The disclosure of instruments (including contingently issuable shares) that could potentially dilute basic earnings per share in the future. Dilutive effect of convertible instruments [Text Block] Antidilutive securities Post balance sheet events [Abstract] Subsequent events [Abstract] Identifies event that occurred after the balance sheet date but before financial statements are issued or available to be issued. Subsequent events [Member] Subsequent Events [Member] Schedule disclosing information related to details of long term financing obligations. Long term financing obligation [Table] Long term financing obligation [Table] Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. Long term financing obligation [Line Items] Debt obligation [Line Items] The amount of contractual commitments for funding research grants. Funding commitment Funding commitment The percentage of funding commitment amount required to be reimbursed as per a research grant agreement of which the amount includes the entire funding commitment plus an additional upcharge. Reimbursement percentage of funding commitment. Reimbursement percentage of funding commitment Amount of the required periodic payments applied to specific interest. Percentage of additional interest on total repayment Percentage of additional interest on total repayment Payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment. Debt instrument, number of installments Number of installments Funding provided for certain types of expenditures in connection with research and development activities over a contractually-defined period from the LuMind Research Down Syndrome Foundation. Grants, LuMind Research Down Syndrome Foundation [Member] Revenue earned from non-repayable sum of money awarded to an entity to carry out a specific purpose as provided in grant agreements. Grant revenue [Member] Grant revenue [Member] Funding provided for certain types of expenditures in connection with research and development activities over a contractually-defined period from the Michael J. Fox Foundation. Grants, Michael J. Fox Foundation [Member] Grant from Michael J. Fox Foundation [Member] The number of grants received. Number of grants Number of grants received The period over which collaborating entities are contracted to perform research, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Collaborative agreement, Joint research collaboration period Period of joint research agreement Skane University Hospital is a university hospital in Scania, Sweden. Skane University Hospital [Member] Skane University Hospital [Member] The research and development of a vaccine for the treatment of Alzheimer's disease. Tau Vaccine in AD [Member] Tau Vaccine in AD [Member] The amount that the entity is eligible to receive for regulatory, commercialization and sales milestones from a collaborative agreement. Collaborative agreement, Collaboration contract receivable for regulatory, commercialization and sales milestones Collaboration contract receivable for regulatory, commercialization and sales milestones The amount that the entity is eligible to receive for clinical milestones from a collaborative agreement.. Collaborative agreement, Collaboration contract receivable for clinical milestones Collaboration contract receivable for clinical milestones The research and development of medicines for the treatment of Alzheimer's disease through molecular imaging. Tau-PET imaging agent in AD [Member] Tau-PET Imaging Agent in AD [Member] The disclosure of detailed information about carrying amounts of financial assets and financial liabilities. Disclosure of detailed information about carrying amounts of financial assets and financial liabilities [Table Text Block] Carrying amounts of financial assets and financial liabilities The 2006 contractual research agreement associated with collaboration with Genentech. Collaboration agreement of 2006, Genentech [Member] 2006 Agreement with Genentech [Member] The research and development of medicines for the treatment of Alzheimer's disease. Anti-Abeta antibody in AD [Member] Anti-Abeta Antibody in AD [Member] Financial assets and liabilities [Abstract] Financial assets and liabilities [Abstract] Financial risks [Abstract] Financial risks [Abstract] The percentage increase to interest rate at the end of the reporting period. Percentage of increase in interest rates Percentage of increase in interest rates The periodic interval in which the entity performs a rolling forecast of the entity's cash position. Liquidity management, rolling forecast period Cash position rolling forecast period The number of financial institutions holding the entity's deposits of cash and cash equivalents and short-term financial assets. Number of financial institutions holding, cash and cash equivalents and short-term financial assets Number of financial institutions holding cash and cash equivalents and short-term financial assets The expected period over which a debt obligation is expected to be extinguished in full. Borrowings, debt extinguishment period Expected debt obligation payoff period The decrease in net loss arising from a decrease in the interest rate. Decrease in net loss, interest rate decrease Net loss for period decrease, due to decrease in interest rate The percentage increase to spot exchange rate at the end of the reporting period. Closing foreign exchange rate, increase Percentage exchange rate strengthened The percentage decrease to spot exchange rate at the end of the reporting period. Closing foreign exchange rate, decrease Percentage exchange rate weakened This member stands for short-term lease liabilities. Short-term lease liabilities [Member] Short-term Lease Liabilities [Member] This member stands for trade and other payables. Trade and Other Payables [Member] The decrease in net loss arising from a increase in the foreign exchange rate. Decrease in net loss, foreign exchange rate increase Net loss for period decrease, result of foreign exchange rate increase The percentage decrease to interest rate at the end of the reporting period. Percentage of decrease in interest rates Percentage of decrease in interest rates This member stands for accrued expenses. Accrued Expenses [Member] The increase in net loss arising from a increase in the interest rate. Increase in net loss, interest rate increase Net loss for period increase, due to increase in interest rate This member represents receivables classified as other. Other receivables [Member] Other Current Receivables [Member] This member represents cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. Cash on hand and cash equivalents [Member] Cash and Cash Equivalents [Member] This member represents financial assets classified as long-term. Long-term Financial Assets [Member] This member represents financial assets classified as short-term. Short-term Financial Assets [Member] Antidilutive securities [Abstract] The number of dilutive potential ordinary shares that relate to the assumed exercise of the entity's share options and potential ordinary shares that relate to the assumed conversion of the entity's convertible instruments. Dilutive effect of share options and convertible instruments on number of ordinary shares Total (in shares) The number of dilutive restricted share awards subject to future vesting that relate to the assumed exercise of the entity's incentive share options. Dilutive effect of Restricted share awards subject to future vesting Restricted share awards subject to future vesting (in shares) The number of dilutive share options that relate to the assumed exercise of the entity's share options. Dilutive effect of share options issued and outstanding Share options issued and outstanding (in-the-money) (in shares) The period or time limit over which financial losses of the entity for preceding years can be deducted from the taxable revenue for a period. Income tax loss, Carryforward period Tax loss carryforward period Number of reportable segments reported by the entity. Reportable segments, number Number of reportable segments Number of operating segments reported by the entity. Operating segments, number Number of operating segments