XML 93 R56.htm IDEA: XBRL DOCUMENT v3.8.0.1

Income Tax Credit - Additional Information (Details) - GBP (£) £ in Millions				12 Months Ended
	Apr. 01, 2020	Apr. 01, 2017	Oct. 26, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure Of Temporary Difference Unused Tax Losses And Unused Tax Credits [Line Items]
Temporary differences and cumulative carry forward tax losses for which deferred tax has not been recognized				£ 40.7	£ 32.5	£ 10.1
U.K.
Disclosure Of Temporary Difference Unused Tax Losses And Unused Tax Credits [Line Items]
Applicable tax rate		19.00%	20.00%	19.25%	20.00%	20.25%
Scenario Forecast | U.K.
Disclosure Of Temporary Difference Unused Tax Losses And Unused Tax Credits [Line Items]
Applicable tax rate	17.00%
Applicable tax rate initially declared	18.00%
Percentage of change in tax rate	1.00%

X

- Definition

The applicable income tax rate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2017-01-01
-Paragraph 81
-Subparagraph c
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_c_ii&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_ApplicableTaxRate
Namespace Prefix:	ifrs-full_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The amount of deductible temporary differences for which no deferred tax asset is recognised in the statement of financial position. [Refer: Temporary differences [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2017-01-01
-Paragraph 81
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_e&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_DeductibleTemporaryDifferencesForWhichNoDeferredTaxAssetIsRecognised
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

X

- Definition

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.

+ References

No definition available.

+ Details

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

X

- Definition

The tax rate effect on the reconciliation between the average effective tax rate and the applicable tax rate resulting from a change in tax rate. [Refer: Average effective tax rate; Applicable tax rate]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2017-01-01
-Paragraph 81
-Subparagraph c
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_c_ii&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_TaxRateEffectFromChangeInTaxRate
Namespace Prefix:	ifrs-full_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Applicable tax rate initially declared.

+ References

No definition available.

+ Details

Name:	ncna_ApplicableTaxRateInitiallyDeclared
Namespace Prefix:	ncna_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	ifrs-full_GeographicalAreasAxis=ifrs-full_CountryOfDomicileMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementScenarioAxis=us-gaap_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: