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The amount of residual interest in the assets of the entity after deducting all its liabilities.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Name:	ifrs-full_Equity
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The increase (decrease) in equity resulting from the exercise of options.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The increase in equity through the issue of equity instruments.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The number of share options exercised in a share-based payment arrangement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The number of shares issued by the entity, for which full payment has been received.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The amount of cost related to the issuance of shares.

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Adjustment of reduction of share premium.

No definition available.

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Period Type:	duration

Bonus shares issued.

No definition available.

Name:	ncna_BonusSharesIssued
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Issue of shares on exercise of options.

No definition available.

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Namespace Prefix:	ncna_
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Balance Type:	na
Period Type:	duration

Number of share of issued capital.

No definition available.