<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.22.0.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>1983</ContextCount>
  <ElementCount>1029</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>482</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>27</UnitCount>
  <MyReports>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>00090 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DocumentDocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>00100 - Statement - Consolidated income statement</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/StatementConsolidatedIncomeStatement</Role>
      <ShortName>Consolidated income statement</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>00200 - Statement - Consolidated statement of comprehensive income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/StatementConsolidatedStatementOfComprehensiveIncome</Role>
      <ShortName>Consolidated statement of comprehensive income</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>00205 - Statement - Consolidated statement of comprehensive income (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/StatementConsolidatedStatementOfComprehensiveIncomeParenthetical</Role>
      <ShortName>Consolidated statement of comprehensive income (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>00300 - Statement - Consolidated balance sheet</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/StatementConsolidatedBalanceSheet</Role>
      <ShortName>Consolidated balance sheet</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>00400 - Statement - Condensed consolidated statement of changes in equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/StatementCondensedConsolidatedStatementOfChangesInEquity</Role>
      <ShortName>Condensed consolidated statement of changes in equity</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>00405 - Statement - Condensed consolidated statement of changes in equity (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/StatementCondensedConsolidatedStatementOfChangesInEquityParenthetical</Role>
      <ShortName>Condensed consolidated statement of changes in equity (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>00500 - Statement - Consolidated cash flow statement</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/StatementConsolidatedCashFlowStatement</Role>
      <ShortName>Consolidated cash flow statement</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>00505 - Statement - Consolidated cash flow statement (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/StatementConsolidatedCashFlowStatementParenthetical</Role>
      <ShortName>Consolidated cash flow statement (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>10001 - Disclosure - Accounting policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAccountingPolicies</Role>
      <ShortName>Accounting policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>10101 - Disclosure - Net interest income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureNetInterestIncome</Role>
      <ShortName>Net interest income</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>10201 - Disclosure - Non-interest income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureNonInterestIncome</Role>
      <ShortName>Non-interest income</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>10301 - Disclosure - Operating expenses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOperatingExpenses</Role>
      <ShortName>Operating expenses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>10401 - Disclosure - Segmental analysis</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureSegmentalAnalysis</Role>
      <ShortName>Segmental analysis</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>10501 - Disclosure - Pensions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosurePensions</Role>
      <ShortName>Pensions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>10601 - Disclosure - Auditor's remuneration</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAuditorSRemuneration</Role>
      <ShortName>Auditor's remuneration</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>10701 - Disclosure - Tax</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTax</Role>
      <ShortName>Tax</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>10801 - Disclosure - Discontinued operations and assets and liabilities of disposal groups</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDiscontinuedOperationsAndAssetsAndLiabilitiesOfDisposalGroups</Role>
      <ShortName>Discontinued operations and assets and liabilities of disposal groups</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>10901 - Disclosure - Earnings per share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureEarningsPerShare</Role>
      <ShortName>Earnings per share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>11001 - Disclosure - Financial instruments - classification</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsClassification</Role>
      <ShortName>Financial instruments - classification</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>11101 - Disclosure - Financial instruments - valuation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsValuation</Role>
      <ShortName>Financial instruments - valuation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>11201 - Disclosure - Financial instruments - maturity analysis</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsMaturityAnalysis</Role>
      <ShortName>Financial instruments - maturity analysis</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>11301 - Disclosure - Trading assets and liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTradingAssetsAndLiabilities</Role>
      <ShortName>Trading assets and liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>11401 - Disclosure - Derivatives</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDerivatives</Role>
      <ShortName>Derivatives</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>11501 - Disclosure - Loan impairment provisions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureLoanImpairmentProvisions</Role>
      <ShortName>Loan impairment provisions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>11601 - Disclosure - Other financial assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOtherFinancialAssets</Role>
      <ShortName>Other financial assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>11701 - Disclosure - Intangible assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureIntangibleAssets</Role>
      <ShortName>Intangible assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>11801 - Disclosure - Other assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOtherAssets</Role>
      <ShortName>Other assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>11901 - Disclosure - Other financial liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOtherFinancialLiabilities</Role>
      <ShortName>Other financial liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>12001 - Disclosure - Subordinated liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureSubordinatedLiabilities</Role>
      <ShortName>Subordinated liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>12101 - Disclosure - Other liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOtherLiabilities</Role>
      <ShortName>Other liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>12201 - Disclosure - Share capital and other equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureShareCapitalAndOtherEquity</Role>
      <ShortName>Share capital and other equity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>12301 - Disclosure - Leases</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureLeases</Role>
      <ShortName>Leases</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>12401 - Disclosure - Structured entities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureStructuredEntities</Role>
      <ShortName>Structured entities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>12501 - Disclosure - Asset transfers</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAssetTransfers</Role>
      <ShortName>Asset transfers</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>12601 - Disclosure - Capital resources</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureCapitalResources</Role>
      <ShortName>Capital resources</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>12701 - Disclosure - Memorandum items</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureMemorandumItems</Role>
      <ShortName>Memorandum items</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>12801 - Disclosure - Analysis of the net investment in business interests and intangible assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAnalysisOfNetInvestmentInBusinessInterestsAndIntangibleAssets</Role>
      <ShortName>Analysis of the net investment in business interests and intangible assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>38</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>12901 - Disclosure - Analysis of changes in financing during the year</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAnalysisOfChangesInFinancingDuringYear</Role>
      <ShortName>Analysis of changes in financing during the year</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>13001 - Disclosure - Analysis of cash and cash equivalents</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAnalysisOfCashAndCashEquivalents</Role>
      <ShortName>Analysis of cash and cash equivalents</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>13101 - Disclosure - Directors' and key management remuneration</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDirectorsAndKeyManagementRemuneration</Role>
      <ShortName>Directors' and key management remuneration</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>13201 - Disclosure - Transactions with directors and key management</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTransactionsWithDirectorsAndKeyManagement</Role>
      <ShortName>Transactions with directors and key management</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>13301 - Disclosure - Related parties</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureRelatedParties</Role>
      <ShortName>Related parties</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>13401 - Disclosure - Post balance sheet events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosurePostBalanceSheetEvents</Role>
      <ShortName>Post balance sheet events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>20002 - Disclosure - Accounting policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAccountingPoliciesPolicies</Role>
      <ShortName>Accounting policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureAccountingPolicies</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>30003 - Disclosure - Accounting policies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAccountingPoliciesTables</Role>
      <ShortName>Accounting policies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureAccountingPolicies</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>30103 - Disclosure - Net interest income (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureNetInterestIncomeTables</Role>
      <ShortName>Net interest income (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureNetInterestIncome</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>30203 - Disclosure - Non-interest income (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureNonInterestIncomeTables</Role>
      <ShortName>Non-interest income (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureNonInterestIncome</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>30303 - Disclosure - Operating expenses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOperatingExpensesTables</Role>
      <ShortName>Operating expenses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureOperatingExpenses</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>30403 - Disclosure - Segmental analysis (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureSegmentalAnalysisTables</Role>
      <ShortName>Segmental analysis (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureSegmentalAnalysis</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>30503 - Disclosure - Pensions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosurePensionsTables</Role>
      <ShortName>Pensions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosurePensions</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>30603 - Disclosure - Auditor's remuneration (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAuditorSRemunerationTables</Role>
      <ShortName>Auditor's remuneration (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureAuditorSRemuneration</ParentRole>
      <Position>52</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>30703 - Disclosure - Tax (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTaxTables</Role>
      <ShortName>Tax (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureTax</ParentRole>
      <Position>53</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>30803 - Disclosure - Discontinued operations and assets and liabilities of disposal groups (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDiscontinuedOperationsAndAssetsAndLiabilitiesOfDisposalGroupsTables</Role>
      <ShortName>Discontinued operations and assets and liabilities of disposal groups (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureDiscontinuedOperationsAndAssetsAndLiabilitiesOfDisposalGroups</ParentRole>
      <Position>54</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>30903 - Disclosure - Earnings per share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureEarningsPerShareTables</Role>
      <ShortName>Earnings per share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureEarningsPerShare</ParentRole>
      <Position>55</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>31003 - Disclosure - Financial instruments - classification (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsClassificationTables</Role>
      <ShortName>Financial instruments - classification (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureFinancialInstrumentsClassification</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>31103 - Disclosure - Financial instruments - valuation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsValuationTables</Role>
      <ShortName>Financial instruments - valuation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureFinancialInstrumentsValuation</ParentRole>
      <Position>57</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>31203 - Disclosure - Financial Instruments - maturity analysis (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsMaturityAnalysisTables</Role>
      <ShortName>Financial Instruments - maturity analysis (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>31303 - Disclosure - Trading assets and liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTradingAssetsAndLiabilitiesTables</Role>
      <ShortName>Trading assets and liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureTradingAssetsAndLiabilities</ParentRole>
      <Position>59</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>31403 - Disclosure - Derivatives (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDerivativesTables</Role>
      <ShortName>Derivatives (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureDerivatives</ParentRole>
      <Position>60</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>31503 - Disclosure - Loan impairment provisions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureLoanImpairmentProvisionsTables</Role>
      <ShortName>Loan impairment provisions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureLoanImpairmentProvisions</ParentRole>
      <Position>61</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>31603 - Disclosure - Other financial assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOtherFinancialAssetsTables</Role>
      <ShortName>Other financial assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureOtherFinancialAssets</ParentRole>
      <Position>62</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>31703 - Disclosure - Intangible assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureIntangibleAssetsTables</Role>
      <ShortName>Intangible assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureIntangibleAssets</ParentRole>
      <Position>63</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>31803 - Disclosure - Other assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOtherAssetsTables</Role>
      <ShortName>Other assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureOtherAssets</ParentRole>
      <Position>64</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>31903 - Disclosure - Other financial liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOtherFinancialLiabilitiesTables</Role>
      <ShortName>Other financial liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureOtherFinancialLiabilities</ParentRole>
      <Position>65</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>32003 - Disclosure - Subordinated liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureSubordinatedLiabilitiesTables</Role>
      <ShortName>Subordinated liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureSubordinatedLiabilities</ParentRole>
      <Position>66</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>32103 - Disclosure - Other liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOtherLiabilitiesTables</Role>
      <ShortName>Other liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureOtherLiabilities</ParentRole>
      <Position>67</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>32203 - Disclosure - Share capital and other equity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureShareCapitalAndOtherEquityTables</Role>
      <ShortName>Share capital and other equity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureShareCapitalAndOtherEquity</ParentRole>
      <Position>68</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>32303 - Disclosure - Leases (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureLeasesTables</Role>
      <ShortName>Leases (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureLeases</ParentRole>
      <Position>69</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>32403 - Disclosure - Structured entities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureStructuredEntitiesTables</Role>
      <ShortName>Structured entities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureStructuredEntities</ParentRole>
      <Position>70</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>32503 - Disclosure - Asset transfers (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAssetTransfersTables</Role>
      <ShortName>Asset transfers (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureAssetTransfers</ParentRole>
      <Position>71</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>32603 - Disclosure - Capital resources (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureCapitalResourcesTables</Role>
      <ShortName>Capital resources (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureCapitalResources</ParentRole>
      <Position>72</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>32703 - Disclosure - Memorandum items (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureMemorandumItemsTables</Role>
      <ShortName>Memorandum items (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureMemorandumItems</ParentRole>
      <Position>73</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>32803 - Disclosure - Analysis of the net investment in business interests and intangible assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAnalysisOfNetInvestmentInBusinessInterestsAndIntangibleAssetsTables</Role>
      <ShortName>Analysis of the net investment in business interests and intangible assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureAnalysisOfNetInvestmentInBusinessInterestsAndIntangibleAssets</ParentRole>
      <Position>74</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>32903 - Disclosure - Analysis of changes in financing during the year (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAnalysisOfChangesInFinancingDuringYearTables</Role>
      <ShortName>Analysis of changes in financing during the year (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureAnalysisOfChangesInFinancingDuringYear</ParentRole>
      <Position>75</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>33003 - Disclosure - Analysis of cash and cash equivalents (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAnalysisOfCashAndCashEquivalentsTables</Role>
      <ShortName>Analysis of cash and cash equivalents (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureAnalysisOfCashAndCashEquivalents</ParentRole>
      <Position>76</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>33103 - Disclosure - Directors' and key management remuneration (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDirectorsAndKeyManagementRemunerationTables</Role>
      <ShortName>Directors' and key management remuneration (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureDirectorsAndKeyManagementRemuneration</ParentRole>
      <Position>77</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>33203 - Disclosure - Transactions with directors and key management (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTransactionsWithDirectorsAndKeyManagementTables</Role>
      <ShortName>Transactions with directors and key management (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureTransactionsWithDirectorsAndKeyManagement</ParentRole>
      <Position>78</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>40001 - Disclosure - Accounting policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAccountingPoliciesDetails</Role>
      <ShortName>Accounting policies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureAccountingPoliciesTables</ParentRole>
      <Position>79</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>40101 - Disclosure - Net interest income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureNetInterestIncomeDetails</Role>
      <ShortName>Net interest income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureNetInterestIncomeTables</ParentRole>
      <Position>80</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>40201 - Disclosure - Non-interest income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureNonInterestIncomeDetails</Role>
      <ShortName>Non-interest income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureNonInterestIncomeTables</ParentRole>
      <Position>81</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>40301 - Disclosure - Operating expenses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOperatingExpensesDetails</Role>
      <ShortName>Operating expenses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureOperatingExpensesTables</ParentRole>
      <Position>82</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>40302 - Disclosure - Operating expenses - Continuing operations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOperatingExpensesContinuingOperationsDetails</Role>
      <ShortName>Operating expenses - Continuing operations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>40303 - Disclosure - Operating expenses - Share-based payments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOperatingExpensesShareBasedPaymentsDetails</Role>
      <ShortName>Operating expenses - Share-based payments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>84</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>40304 - Disclosure - Operating expenses - Bonus awards (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOperatingExpensesBonusAwardsDetails</Role>
      <ShortName>Operating expenses - Bonus awards (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>85</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>40305 - Disclosure - Operating expenses - Bonus awards reconciliation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOperatingExpensesBonusAwardsReconciliationDetails</Role>
      <ShortName>Operating expenses - Bonus awards reconciliation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>40306 - Disclosure - Operating expenses - Bonus awards - Actual and Expected (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOperatingExpensesBonusAwardsActualAndExpectedDetails</Role>
      <ShortName>Operating expenses - Bonus awards - Actual and Expected (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>87</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>40401 - Disclosure - Segmental analysis - Operating profit/(loss) before tax (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureSegmentalAnalysisOperatingProfitLossBeforeTaxDetails</Role>
      <ShortName>Segmental analysis - Operating profit/(loss) before tax (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>88</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>40402 - Disclosure - Segmental analysis - Total revenue (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureSegmentalAnalysisTotalRevenueDetails</Role>
      <ShortName>Segmental analysis - Total revenue (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>89</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>40403 - Disclosure - Segmental analysis - Net fees and commissions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureSegmentalAnalysisNetFeesAndCommissionsDetails</Role>
      <ShortName>Segmental analysis - Net fees and commissions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>90</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>40404 - Disclosure - Segmental analysis - Assets and liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureSegmentalAnalysisAssetsAndLiabilitiesDetails</Role>
      <ShortName>Segmental analysis - Assets and liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>91</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>40405 - Disclosure - Segmental analysis - Goodwill (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureSegmentalAnalysisGoodwillDetails</Role>
      <ShortName>Segmental analysis - Goodwill (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>92</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>40406 - Disclosure - Segmental analysis - Geographical segments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureSegmentalAnalysisGeographicalSegmentsDetails</Role>
      <ShortName>Segmental analysis - Geographical segments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>93</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>40501 - Disclosure - Pensions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosurePensionsDetails</Role>
      <ShortName>Pensions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosurePensionsTables</ParentRole>
      <Position>94</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R95.htm</HtmlFileName>
      <LongName>40502 - Disclosure - Pensions - Investment strategy (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosurePensionsInvestmentStrategyDetails</Role>
      <ShortName>Pensions - Investment strategy (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>95</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R96.htm</HtmlFileName>
      <LongName>40503 - Disclosure - Pensions - Changes in value of net pension (assets)/liability (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosurePensionsChangesInValueOfNetPensionAssetsLiabilityDetails</Role>
      <ShortName>Pensions - Changes in value of net pension (assets)/liability (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>96</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>40504 - Disclosure - Pensions - Amounts in the Financial statements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosurePensionsAmountsInFinancialStatementsDetails</Role>
      <ShortName>Pensions - Amounts in the Financial statements (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>97</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>40505 - Disclosure - Pensions - Income statement charge (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosurePensionsIncomeStatementChargeDetails</Role>
      <ShortName>Pensions - Income statement charge (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>98</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R99.htm</HtmlFileName>
      <LongName>40506 - Disclosure - Pensions - Funding and contributions by the Group and most significant assumptions used for the Main Scheme (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosurePensionsFundingAndContributionsByGroupAndMostSignificantAssumptionsUsedForMainSchemeDetails</Role>
      <ShortName>Pensions - Funding and contributions by the Group and most significant assumptions used for the Main Scheme (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>99</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R100.htm</HtmlFileName>
      <LongName>40507 - Disclosure - Pensions - Sensitivities of the present value of defined benefit obligation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosurePensionsSensitivitiesOfPresentValueOfDefinedBenefitObligationDetails</Role>
      <ShortName>Pensions - Sensitivities of the present value of defined benefit obligation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>100</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R101.htm</HtmlFileName>
      <LongName>40508 - Disclosure - Pensions - History of defined benefit schemes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosurePensionsHistoryOfDefinedBenefitSchemesDetails</Role>
      <ShortName>Pensions - History of defined benefit schemes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>101</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R102.htm</HtmlFileName>
      <LongName>40601 - Disclosure - Auditor's remuneration (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAuditorSRemunerationDetails</Role>
      <ShortName>Auditor's remuneration (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureAuditorSRemunerationTables</ParentRole>
      <Position>102</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R103.htm</HtmlFileName>
      <LongName>40701 - Disclosure - Tax - Tax charge (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTaxTaxChargeDetails</Role>
      <ShortName>Tax - Tax charge (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>103</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R104.htm</HtmlFileName>
      <LongName>40702 - Disclosure - Tax - Reconciliation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTaxReconciliationDetails</Role>
      <ShortName>Tax - Reconciliation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>104</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R105.htm</HtmlFileName>
      <LongName>40703 - Disclosure - Tax - Analysis of deferred tax (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTaxAnalysisOfDeferredTaxDetails</Role>
      <ShortName>Tax - Analysis of deferred tax (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>105</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R106.htm</HtmlFileName>
      <LongName>40704 - Disclosure - Tax - Deferred tax reconciliation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTaxDeferredTaxReconciliationDetails</Role>
      <ShortName>Tax - Deferred tax reconciliation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>106</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R107.htm</HtmlFileName>
      <LongName>40705 - Disclosure - Tax - Tax losses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTaxTaxLossesDetails</Role>
      <ShortName>Tax - Tax losses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>107</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R108.htm</HtmlFileName>
      <LongName>40706 - Disclosure - Tax - Other (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTaxOtherDetails</Role>
      <ShortName>Tax - Other (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>108</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R109.htm</HtmlFileName>
      <LongName>40801 - Disclosure - Discontinued operations and assets and liabilities of disposal groups (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDiscontinuedOperationsAndAssetsAndLiabilitiesOfDisposalGroupsDetails</Role>
      <ShortName>Discontinued operations and assets and liabilities of disposal groups (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureDiscontinuedOperationsAndAssetsAndLiabilitiesOfDisposalGroupsTables</ParentRole>
      <Position>109</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R110.htm</HtmlFileName>
      <LongName>40802 - Disclosure - Discontinued operations and assets and liabilities of disposal groups - Profit (loss) from discontinued operations, net of tax (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDiscontinuedOperationsAndAssetsAndLiabilitiesOfDisposalGroupsProfitLossFromDiscontinuedOperationsNetOfTaxDetails</Role>
      <ShortName>Discontinued operations and assets and liabilities of disposal groups - Profit (loss) from discontinued operations, net of tax (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureDiscontinuedOperationsAndAssetsAndLiabilitiesOfDisposalGroupsTables</ParentRole>
      <Position>110</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R111.htm</HtmlFileName>
      <LongName>40803 - Disclosure - Discontinued operations and assets and liabilities of disposal groups - Assets and liabilities of disposal groups (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDiscontinuedOperationsAndAssetsAndLiabilitiesOfDisposalGroupsAssetsAndLiabilitiesOfDisposalGroupsDetails</Role>
      <ShortName>Discontinued operations and assets and liabilities of disposal groups - Assets and liabilities of disposal groups (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>111</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R112.htm</HtmlFileName>
      <LongName>40804 - Disclosure - Discontinued operations and assets and liabilities of disposal groups - Operating cash flows attributable to discontinued operations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDiscontinuedOperationsAndAssetsAndLiabilitiesOfDisposalGroupsOperatingCashFlowsAttributableToDiscontinuedOperationsDetails</Role>
      <ShortName>Discontinued operations and assets and liabilities of disposal groups - Operating cash flows attributable to discontinued operations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>112</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R113.htm</HtmlFileName>
      <LongName>40901 - Disclosure - Earnings per share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureEarningsPerShareDetails</Role>
      <ShortName>Earnings per share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureEarningsPerShareTables</ParentRole>
      <Position>113</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R114.htm</HtmlFileName>
      <LongName>41001 - Disclosure - Financial instruments: classification - Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsClassificationAssetsDetails</Role>
      <ShortName>Financial instruments: classification - Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>114</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R115.htm</HtmlFileName>
      <LongName>41002 - Disclosure - Financial instruments: classification - Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsClassificationLiabilitiesDetails</Role>
      <ShortName>Financial instruments: classification - Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>115</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R116.htm</HtmlFileName>
      <LongName>41003 - Disclosure - Financial instruments: classification - Reverse repos and repos (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsClassificationReverseReposAndReposDetails</Role>
      <ShortName>Financial instruments: classification - Reverse repos and repos (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>116</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R117.htm</HtmlFileName>
      <LongName>41004 - Disclosure - Financial Instruments - classification - Offsetable assets and liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsClassificationOffsetableAssetsAndLiabilitiesDetails</Role>
      <ShortName>Financial Instruments - classification - Offsetable assets and liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>117</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R118.htm</HtmlFileName>
      <LongName>41005 - Disclosure - Financial Instruments - classification - IBOR reform (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsClassificationIborReformDetails</Role>
      <ShortName>Financial Instruments - classification - IBOR reform (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>118</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R119.htm</HtmlFileName>
      <LongName>41006 - Disclosure - Financial Instruments - classification - AT1 issuances (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsClassificationAt1IssuancesDetails</Role>
      <ShortName>Financial Instruments - classification - AT1 issuances (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>119</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R120.htm</HtmlFileName>
      <LongName>41101 - Disclosure - Financial instruments: valuation - Hierarchy of assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsValuationHierarchyOfAssetsDetails</Role>
      <ShortName>Financial instruments: valuation - Hierarchy of assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>120</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R121.htm</HtmlFileName>
      <LongName>41102 - Disclosure - Financial instruments: valuation - Hierarchy of liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsValuationHierarchyOfLiabilitiesDetails</Role>
      <ShortName>Financial instruments: valuation - Hierarchy of liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>121</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R122.htm</HtmlFileName>
      <LongName>41103 - Disclosure - Financial instruments: valuation - Adjustments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsValuationAdjustmentsDetails</Role>
      <ShortName>Financial instruments: valuation - Adjustments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>122</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R123.htm</HtmlFileName>
      <LongName>41104 - Disclosure - Financial instruments: valuation - Valuation techniques (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsValuationValuationTechniquesDetails</Role>
      <ShortName>Financial instruments: valuation - Valuation techniques (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>123</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R124.htm</HtmlFileName>
      <LongName>41105 - Disclosure - Financial instruments: valuation - Level 3 Sensitivities of Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsValuationLevel3SensitivitiesOfAssetsDetails</Role>
      <ShortName>Financial instruments: valuation - Level 3 Sensitivities of Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>124</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R125.htm</HtmlFileName>
      <LongName>41106 - Disclosure - Financial instruments: valuation - Level 3 Sensitivities of Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsValuationLevel3SensitivitiesOfLiabilitiesDetails</Role>
      <ShortName>Financial instruments: valuation - Level 3 Sensitivities of Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>125</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R126.htm</HtmlFileName>
      <LongName>41107 - Disclosure - Financial instruments: valuation - Movement in Level 3 portfolios - Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsValuationMovementInLevel3PortfoliosAssetsDetails</Role>
      <ShortName>Financial instruments: valuation - Movement in Level 3 portfolios - Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>126</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R127.htm</HtmlFileName>
      <LongName>41108 - Disclosure - Financial instruments: valuation - Movement in Level 3 portfolios - Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsValuationMovementInLevel3PortfoliosLiabilitiesDetails</Role>
      <ShortName>Financial instruments: valuation - Movement in Level 3 portfolios - Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>127</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R128.htm</HtmlFileName>
      <LongName>41109 - Disclosure - Financial instruments: valuation - Assets at Amortised Cost (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsValuationAssetsAtAmortisedCostDetails</Role>
      <ShortName>Financial instruments: valuation - Assets at Amortised Cost (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>128</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R129.htm</HtmlFileName>
      <LongName>41110 - Disclosure - Financial instruments: valuation - Liabilities at Amortised Cost (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsValuationLiabilitiesAtAmortisedCostDetails</Role>
      <ShortName>Financial instruments: valuation - Liabilities at Amortised Cost (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>129</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R130.htm</HtmlFileName>
      <LongName>41201 - Disclosure - Financial Instruments - maturity analysis - Residual Maturity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsMaturityAnalysisResidualMaturityDetails</Role>
      <ShortName>Financial Instruments - maturity analysis - Residual Maturity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>130</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R131.htm</HtmlFileName>
      <LongName>41202 - Disclosure - Financial Instruments - maturity analysis - Contractual Maturity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureFinancialInstrumentsMaturityAnalysisContractualMaturityDetails</Role>
      <ShortName>Financial Instruments - maturity analysis - Contractual Maturity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>131</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R132.htm</HtmlFileName>
      <LongName>41301 - Disclosure - Trading assets and liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTradingAssetsAndLiabilitiesDetails</Role>
      <ShortName>Trading assets and liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureTradingAssetsAndLiabilitiesTables</ParentRole>
      <Position>132</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R133.htm</HtmlFileName>
      <LongName>41401 - Disclosure - Derivatives - fair value of the hedging derivative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDerivativesFairValueOfHedgingDerivativeDetails</Role>
      <ShortName>Derivatives - fair value of the hedging derivative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>133</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R134.htm</HtmlFileName>
      <LongName>41402 - Disclosure - Derivatives - Notional of hedging instruments affected by interest rate benchmark reform (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDerivativesNotionalOfHedgingInstrumentsAffectedByInterestRateBenchmarkReformDetails</Role>
      <ShortName>Derivatives - Notional of hedging instruments affected by interest rate benchmark reform (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>134</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R135.htm</HtmlFileName>
      <LongName>41403 - Disclosure - Derivatives - Impact of the accumulated amount of fair hedge adjustments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDerivativesImpactOfAccumulatedAmountOfFairHedgeAdjustmentsDetails</Role>
      <ShortName>Derivatives - Impact of the accumulated amount of fair hedge adjustments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>135</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R136.htm</HtmlFileName>
      <LongName>41405 - Disclosure - Derivatives - Risk exposures that will be affected by interest rate benchmark reform (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDerivativesRiskExposuresThatWillBeAffectedByInterestRateBenchmarkReformDetails</Role>
      <ShortName>Derivatives - Risk exposures that will be affected by interest rate benchmark reform (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>136</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R137.htm</HtmlFileName>
      <LongName>41406 - Disclosure - Derivatives - Analysis of cash flow reserve and foreign exchange reserve (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDerivativesAnalysisOfCashFlowReserveAndForeignExchangeReserveDetails</Role>
      <ShortName>Derivatives - Analysis of cash flow reserve and foreign exchange reserve (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>137</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R138.htm</HtmlFileName>
      <LongName>41407 - Disclosure - Derivatives - Hedge ineffectiveness recognised (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDerivativesHedgeIneffectivenessRecognisedDetails</Role>
      <ShortName>Derivatives - Hedge ineffectiveness recognised (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>138</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R139.htm</HtmlFileName>
      <LongName>41408 - Disclosure - Derivatives - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDerivativesNarrativeDetails</Role>
      <ShortName>Derivatives - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>139</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R140.htm</HtmlFileName>
      <LongName>41501 - Disclosure - Loan impairment provisions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureLoanImpairmentProvisionsDetails</Role>
      <ShortName>Loan impairment provisions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureLoanImpairmentProvisionsTables</ParentRole>
      <Position>140</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R141.htm</HtmlFileName>
      <LongName>41601 - Disclosure - Other financial assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOtherFinancialAssetsDetails</Role>
      <ShortName>Other financial assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureOtherFinancialAssetsTables</ParentRole>
      <Position>141</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R142.htm</HtmlFileName>
      <LongName>41701 - Disclosure - Intangible assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureIntangibleAssetsDetails</Role>
      <ShortName>Intangible assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureIntangibleAssetsTables</ParentRole>
      <Position>142</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R143.htm</HtmlFileName>
      <LongName>41702 - Disclosure - Intangible assets - Assumptions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureIntangibleAssetsAssumptionsDetails</Role>
      <ShortName>Intangible assets - Assumptions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>143</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R144.htm</HtmlFileName>
      <LongName>41703 - Disclosure - Intangible assets - Changes to key assumptions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureIntangibleAssetsChangesToKeyAssumptionsDetails</Role>
      <ShortName>Intangible assets - Changes to key assumptions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>144</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R145.htm</HtmlFileName>
      <LongName>41801 - Disclosure - Other assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOtherAssetsDetails</Role>
      <ShortName>Other assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureOtherAssetsTables</ParentRole>
      <Position>145</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R146.htm</HtmlFileName>
      <LongName>41901 - Disclosure - Other financial liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOtherFinancialLiabilitiesDetails</Role>
      <ShortName>Other financial liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureOtherFinancialLiabilitiesTables</ParentRole>
      <Position>146</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R147.htm</HtmlFileName>
      <LongName>42001 - Disclosure - Subordinated liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureSubordinatedLiabilitiesDetails</Role>
      <ShortName>Subordinated liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureSubordinatedLiabilitiesTables</ParentRole>
      <Position>147</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R148.htm</HtmlFileName>
      <LongName>42002 - Disclosure - Subordinated liabilities - Redemption (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureSubordinatedLiabilitiesRedemptionDetails</Role>
      <ShortName>Subordinated liabilities - Redemption (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>148</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R149.htm</HtmlFileName>
      <LongName>42101 - Disclosure - Other liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOtherLiabilitiesDetails</Role>
      <ShortName>Other liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureOtherLiabilitiesTables</ParentRole>
      <Position>149</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R150.htm</HtmlFileName>
      <LongName>42102 - Disclosure - Other liabilities - Provision for liabilities and charges (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureOtherLiabilitiesProvisionForLiabilitiesAndChargesDetails</Role>
      <ShortName>Other liabilities - Provision for liabilities and charges (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>150</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R151.htm</HtmlFileName>
      <LongName>42201 - Disclosure - Share capital and other equity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureShareCapitalAndOtherEquityDetails</Role>
      <ShortName>Share capital and other equity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureShareCapitalAndOtherEquityTables</ParentRole>
      <Position>151</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R152.htm</HtmlFileName>
      <LongName>42202 - Disclosure - Share capital and other equity - Movement in shares (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureShareCapitalAndOtherEquityMovementInSharesDetails</Role>
      <ShortName>Share capital and other equity - Movement in shares (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>152</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R153.htm</HtmlFileName>
      <LongName>42203 - Disclosure - Share capital and other equity - Ordinary shares (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureShareCapitalAndOtherEquityOrdinarySharesDetails</Role>
      <ShortName>Share capital and other equity - Ordinary shares (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>153</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R154.htm</HtmlFileName>
      <LongName>42204 - Disclosure - Share capital and other equity - Non-cumulative preference shares (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureShareCapitalAndOtherEquityNonCumulativePreferenceSharesDetails</Role>
      <ShortName>Share capital and other equity - Non-cumulative preference shares (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>154</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R155.htm</HtmlFileName>
      <LongName>42205 - Disclosure - Share capital and other equity - Paid-in equity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureShareCapitalAndOtherEquityPaidInEquityDetails</Role>
      <ShortName>Share capital and other equity - Paid-in equity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>155</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R156.htm</HtmlFileName>
      <LongName>42206 - Disclosure - Share capital and other equity - Reserves (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureShareCapitalAndOtherEquityReservesDetails</Role>
      <ShortName>Share capital and other equity - Reserves (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>156</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R157.htm</HtmlFileName>
      <LongName>42207 - Disclosure - Share capital and other equity - Cumulative preference shares (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureShareCapitalAndOtherEquityCumulativePreferenceSharesDetails</Role>
      <ShortName>Share capital and other equity - Cumulative preference shares (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>157</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R158.htm</HtmlFileName>
      <LongName>42301 - Disclosure - Leases - Lessee Leases - Amounts recognised in consolidated financial statements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureLeasesLesseeLeasesAmountsRecognisedInConsolidatedFinancialStatementsDetails</Role>
      <ShortName>Leases - Lessee Leases - Amounts recognised in consolidated financial statements (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>158</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R159.htm</HtmlFileName>
      <LongName>42302 - Disclosure - Leases - Lessor Leases - Amounts recognised in consolidated income statement (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureLeasesLessorLeasesAmountsRecognisedInConsolidatedIncomeStatementDetails</Role>
      <ShortName>Leases - Lessor Leases - Amounts recognised in consolidated income statement (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>159</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R160.htm</HtmlFileName>
      <LongName>42303 - Disclosure - Leases - Lessor Leases - Amount receivable under finance leases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureLeasesLessorLeasesAmountReceivableUnderFinanceLeasesDetails</Role>
      <ShortName>Leases - Lessor Leases - Amount receivable under finance leases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>160</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R161.htm</HtmlFileName>
      <LongName>42304 - Disclosure - Leases - Lessor Leases - Nature of operating lease assets on the balance sheet (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureLeasesLessorLeasesNatureOfOperatingLeaseAssetsOnBalanceSheetDetails</Role>
      <ShortName>Leases - Lessor Leases - Nature of operating lease assets on the balance sheet (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>161</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R162.htm</HtmlFileName>
      <LongName>42305 - Disclosure - Leases - Lessor Leases - Undiscounted lease receipts from operating leases and investment properties (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureLeasesLessorLeasesUndiscountedLeaseReceiptsFromOperatingLeasesAndInvestmentPropertiesDetails</Role>
      <ShortName>Leases - Lessor Leases - Undiscounted lease receipts from operating leases and investment properties (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>162</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R163.htm</HtmlFileName>
      <LongName>42401 - Disclosure - Structured entities - Own asset securitisations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureStructuredEntitiesOwnAssetSecuritisationsDetails</Role>
      <ShortName>Structured entities - Own asset securitisations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>163</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R164.htm</HtmlFileName>
      <LongName>42402 - Disclosure - Structured entities - Unconsolidated structured entities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureStructuredEntitiesUnconsolidatedStructuredEntitiesDetails</Role>
      <ShortName>Structured entities - Unconsolidated structured entities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>164</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R165.htm</HtmlFileName>
      <LongName>42501 - Disclosure - Asset transfers (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAssetTransfersDetails</Role>
      <ShortName>Asset transfers (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureAssetTransfersTables</ParentRole>
      <Position>165</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R166.htm</HtmlFileName>
      <LongName>42502 - Disclosure - Asset transfers - Assets pledged as collateral (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAssetTransfersAssetsPledgedAsCollateralDetails</Role>
      <ShortName>Asset transfers - Assets pledged as collateral (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>166</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R167.htm</HtmlFileName>
      <LongName>42503 - Disclosure - Asset transfers - Transferred assets continue to be recorded on Natwest Group's balance sheet (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAssetTransfersTransferredAssetsContinueToBeRecordedOnNatwestGroupSBalanceSheetDetails</Role>
      <ShortName>Asset transfers - Transferred assets continue to be recorded on Natwest Group's balance sheet (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>167</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R168.htm</HtmlFileName>
      <LongName>42601 - Disclosure - Capital resources (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureCapitalResourcesDetails</Role>
      <ShortName>Capital resources (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureCapitalResourcesTables</ParentRole>
      <Position>168</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R169.htm</HtmlFileName>
      <LongName>42701 - Disclosure - Memorandum items - Contingent liabilities and commitments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureMemorandumItemsContingentLiabilitiesAndCommitmentsDetails</Role>
      <ShortName>Memorandum items - Contingent liabilities and commitments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>169</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R170.htm</HtmlFileName>
      <LongName>42702 - Disclosure - Memorandum items - Contractual obligations of future (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureMemorandumItemsContractualObligationsOfFutureDetails</Role>
      <ShortName>Memorandum items - Contractual obligations of future (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>170</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R171.htm</HtmlFileName>
      <LongName>42703 - Disclosure - Memorandum items - Other (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureMemorandumItemsOtherDetails</Role>
      <ShortName>Memorandum items - Other (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>171</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R172.htm</HtmlFileName>
      <LongName>42801 - Disclosure - Analysis of the net investment in business interests and intangible assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAnalysisOfNetInvestmentInBusinessInterestsAndIntangibleAssetsDetails</Role>
      <ShortName>Analysis of the net investment in business interests and intangible assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureAnalysisOfNetInvestmentInBusinessInterestsAndIntangibleAssetsTables</ParentRole>
      <Position>172</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R173.htm</HtmlFileName>
      <LongName>42901 - Disclosure - Analysis of changes in financing during the year (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAnalysisOfChangesInFinancingDuringYearDetails</Role>
      <ShortName>Analysis of changes in financing during the year (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureAnalysisOfChangesInFinancingDuringYearTables</ParentRole>
      <Position>173</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R174.htm</HtmlFileName>
      <LongName>42902 - Disclosure - Analysis of changes in financing during the year - Subordinated liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAnalysisOfChangesInFinancingDuringYearSubordinatedLiabilitiesDetails</Role>
      <ShortName>Analysis of changes in financing during the year - Subordinated liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>174</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R175.htm</HtmlFileName>
      <LongName>43001 - Disclosure - Analysis of cash and cash equivalents (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureAnalysisOfCashAndCashEquivalentsDetails</Role>
      <ShortName>Analysis of cash and cash equivalents (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureAnalysisOfCashAndCashEquivalentsTables</ParentRole>
      <Position>175</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R176.htm</HtmlFileName>
      <LongName>43101 - Disclosure - Directors' and key management remuneration - Directors (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDirectorsAndKeyManagementRemunerationDirectorsDetails</Role>
      <ShortName>Directors' and key management remuneration - Directors (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>176</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R177.htm</HtmlFileName>
      <LongName>43102 - Disclosure - Directors' and key management remuneration - Key management (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureDirectorsAndKeyManagementRemunerationKeyManagementDetails</Role>
      <ShortName>Directors' and key management remuneration - Key management (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>177</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R178.htm</HtmlFileName>
      <LongName>43201 - Disclosure - Transactions with directors and key management (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureTransactionsWithDirectorsAndKeyManagementDetails</Role>
      <ShortName>Transactions with directors and key management (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureTransactionsWithDirectorsAndKeyManagementTables</ParentRole>
      <Position>178</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R179.htm</HtmlFileName>
      <LongName>43301 - Disclosure - Related parties (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosureRelatedPartiesDetails</Role>
      <ShortName>Related parties (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosureRelatedParties</ParentRole>
      <Position>179</Position>
    </Report>
    <Report instance="nwg-20211231x20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R180.htm</HtmlFileName>
      <LongName>43401 - Disclosure - Post balance sheet events (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rbs.com/role/DisclosurePostBalanceSheetEventsDetails</Role>
      <ShortName>Post balance sheet events (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rbs.com/role/DisclosurePostBalanceSheetEvents</ParentRole>
      <Position>180</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File doctype="20-F" original="nwg-20211231x20f.htm">nwg-20211231x20f.htm</File>
    <File>nwg-20211231.xsd</File>
    <File>nwg-20211231_cal.xml</File>
    <File>nwg-20211231_def.xml</File>
    <File>nwg-20211231_lab.xml</File>
    <File>nwg-20211231_pre.xml</File>
    <File>nwg-20211231xex12d1.htm</File>
    <File>nwg-20211231xex12d2.htm</File>
    <File>nwg-20211231xex13d1.htm</File>
    <File>nwg-20211231xex15d1.htm</File>
    <File>nwg-20211231xex15d2.htm</File>
    <File>nwg-20211231xex2d4.htm</File>
    <File>nwg-20211231xex8d1.htm</File>
  </InputFiles>
  <SupplementalFiles>
    <File>nwg-20211231x20f005.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="3796">http://xbrl.ifrs.org/taxonomy/2021-03-24/ifrs-full</BaseTaxonomy>
    <BaseTaxonomy items="109">http://xbrl.sec.gov/dei/2021q4</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
