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Period Type:	duration

Adjustments for increase (decrease) in current deferred income to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Deferred income; Profit (loss)]

No definition available.

Name:	argx_AdjustmentsForIncreaseDecreaseInCurrentDeferredIncome
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Adjustments for increase (decrease) in non current deferred income to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Deferred income; Profit (loss)]

No definition available.

Name:	argx_AdjustmentsForIncreaseDecreaseInNonCurrentDeferredIncome
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The amount of gain (loss) on foreign currency conversion on proceeds from issuance of new shares

No definition available.

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Period Type:	duration

the increase (decrease in cash and cash equivalents excluding exchange gain (loss).

No definition available.

Name:	argx_IncreaseDecreaseInCashAndCashEquivalentsExcludingExchangeGainLoss
Namespace Prefix:	argx_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

The increase (decrease) in current financial assets.

No definition available.

Name:	argx_IncreaseDecreaseInCurrentFinancialAssets
Namespace Prefix:	argx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

No definition available.

Name:	argx_MovementsInCurrentAssetsOrLiabilitiesAbstract
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Period Type:	duration

n/a.

No definition available.

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Net cash increase (decrease) after non-cash item adjustments.

No definition available.

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Adjustments for amortisation expense to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Profit (loss); Depreciation and amortisation expense]

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Adjustments for decrease (increase) in other current assets to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Other current assets; Profit (loss)]

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Adjustments for decrease (increase) in trade and other receivables to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Trade and other receivables; Profit (loss)]

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Adjustments for depreciation expense to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Profit (loss)]

Name:	ifrs-full_AdjustmentsForDepreciationExpense
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Adjustments for fair value losses (gains) to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Profit (loss)]

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Adjustments for increase (decrease) in trade and other payables to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Trade and other payables; Profit (loss)]

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Adjustments for losses (gains) on disposal of non-current assets to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Non-current assets; Profit (loss)]

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Adjustments for provisions to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Provisions; Profit (loss)]

Name:	ifrs-full_AdjustmentsForProvisions
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

No definition available.

Name:	ifrs-full_AdjustmentsForReconcileProfitLossAbstract
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Balance Type:	na
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Adjustments for share-based payments to reconcile profit (loss) to net cash flow from (used in) operating activities. [Refer: Profit (loss)]

Name:	ifrs-full_AdjustmentsForSharebasedPayments
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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The amount of 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. [Refer: Cash; Cash equivalents]

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-Name IFRS
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-Paragraph B13
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-Paragraph 54
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-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_54_i&doctype=Standard
-URIDate 2019-03-27

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The cash flows from (used in) financing activities, which are activities that result in changes in the size and composition of the contributed equity and borrowings of the entity.

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-Name IAS
-Number 7
-IssueDate 2019-01-01
-Paragraph 10
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_10&doctype=Standard
-URIDate 2019-03-27

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-Name IAS
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-Paragraph 50
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-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_50_d&doctype=Standard
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Name:	ifrs-full_CashFlowsFromUsedInFinancingActivities
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

No definition available.

Name:	ifrs-full_CashFlowsFromUsedInFinancingActivitiesAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The cash flows from (used in) investing activities, which are the acquisition and disposal of long-term assets and other investments not included in cash equivalents.

Name:	ifrs-full_CashFlowsFromUsedInInvestingActivities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

No definition available.

Name:	ifrs-full_CashFlowsFromUsedInInvestingActivitiesAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
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The cash flows from (used in) operating activities, which are the principal revenue-producing activities of the entity and other activities that are not investing or financing activities. [Refer: Revenue]

Name:	ifrs-full_CashFlowsFromUsedInOperatingActivities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

No definition available.

Name:	ifrs-full_CashFlowsFromUsedInOperatingActivitiesAbstract
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The cash from (used in) the entity's operations.

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-Name IAS
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-Section A Statement of cash flows for an entity other than a financial institution
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&doctype=Illustrative%20Examples&dita_xref=IAS07_IE_A_TI
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-Name IAS
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-IssueDate 2019-01-01
-Paragraph 20
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_20&doctype=Standard
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Name:	ifrs-full_CashFlowsFromUsedInOperations
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
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The effect of exchange rate changes on cash and cash equivalents held or due in a foreign currency. [Refer: Cash and cash equivalents]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2019-01-01
-Paragraph 25
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_25&doctype=Standard
-URIDate 2019-03-27

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-Name IAS
-Number 7
-IssueDate 2019-01-01
-Paragraph 28
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_28&doctype=Standard
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Name:	ifrs-full_EffectOfExchangeRateChangesOnCashAndCashEquivalents
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The cash flows from income taxes paid or refunded, classified as operating activities. [Refer: Income taxes paid (refund)]

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-Name IAS
-Number 7
-IssueDate 2019-01-01
-Paragraph 35
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_35&doctype=Standard
-URIDate 2019-03-27

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-Name IAS
-Number 7
-IssueDate 2019-01-01
-Paragraph 14
-Subparagraph f
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_14_f&doctype=Standard
-URIDate 2019-03-27

Name:	ifrs-full_IncomeTaxesPaidRefundClassifiedAsOperatingActivities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The cash outflow for interest paid, classified as operating activities.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2019-01-01
-Paragraph 31
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_31&doctype=Standard
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Name:	ifrs-full_InterestPaidClassifiedAsOperatingActivities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The cash inflow from interest received, classified as investing activities.

Name:	ifrs-full_InterestReceivedClassifiedAsInvestingActivities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The cash outflow for share issue costs.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 7
-IssueDate 2019-01-01
-Paragraph 17
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_17&doctype=Standard
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Name:	ifrs-full_PaymentsForShareIssueCosts
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The cash outflow for payment of lease liabilities, classified as financing activities. [Refer: Lease liabilities]

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-Name IAS
-Number 7
-IssueDate 2019-01-01
-Paragraph 17
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_17_e&doctype=Standard
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Name:	ifrs-full_PaymentsOfLeaseLiabilitiesClassifiedAsFinancingActivities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The cash inflow from the exercise of options.

Name:	ifrs-full_ProceedsFromExerciseOfOptions
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The cash inflow from the issuing of ordinary shares. [Refer: Ordinary shares [member]]

Name:	ifrs-full_ProceedsFromIssueOfOrdinaryShares
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The profit (loss) from operating activities of the entity. [Refer: Profit (loss)]

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-Name IAS
-Number 32
-IssueDate 2019-01-01
-Paragraph IE33
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-URIDate 2019-03-27

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 85
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_85&doctype=Standard
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Name:	ifrs-full_ProfitLossFromOperatingActivities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The cash outflow for the purchases of intangible assets, classified as investing activities. [Refer: Intangible assets other than goodwill]

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 7
-IssueDate 2019-01-01
-Paragraph 16
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2019-en-r&anchor=para_16_a&doctype=Standard
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Name:	ifrs-full_PurchaseOfIntangibleAssetsClassifiedAsInvestingActivities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The cash outflow for the purchases of property, plant and equipment, classified as investing activities. [Refer: Property, plant and equipment]