<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.23.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>197</ContextCount>
  <ElementCount>460</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>60</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>9</UnitCount>
  <MyReports>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>100000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DocumentDocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>100010 - Statement - Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_StatementConsolidatedBalanceSheets</Role>
      <ShortName>Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>100030 - Statement - Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Consolidated Balance Sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>100040 - Statement - Consolidated Statements of Operations and Comprehensive Income (Loss)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/StatementConsolidatedStatementsOfOperationsAndComprehensiveIncomeLoss</Role>
      <ShortName>Consolidated Statements of Operations and Comprehensive Income (Loss)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>100050 - Statement - Consolidated Statements of Shareholder's Equity (Deficit)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_StatementConsolidatedStatementsOfShareholderSEquityDeficit</Role>
      <ShortName>Consolidated Statements of Shareholder's Equity (Deficit)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>100060 - Statement - Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows</Role>
      <ShortName>Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>100070 - Disclosure - General</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureGeneral</Role>
      <ShortName>General</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>100080 - Disclosure - Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>100090 - Disclosure - Accounting Standards</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureAccountingStandards</Role>
      <ShortName>Accounting Standards</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>100100 - Disclosure - Revenues</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureRevenues</Role>
      <ShortName>Revenues</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>100110 - Disclosure - Prepaid Expenses and Other Current Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosurePrepaidExpensesAndOtherCurrentAssets</Role>
      <ShortName>Prepaid Expenses and Other Current Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>100120 - Disclosure - Goodwill and Other Intangible Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssets</Role>
      <ShortName>Goodwill and Other Intangible Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>100130 - Disclosure - Property and Equipment</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosurePropertyAndEquipment</Role>
      <ShortName>Property and Equipment</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>100140 - Disclosure - Accrued Expenses and Other Current Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureAccruedExpensesAndOtherCurrentLiabilities</Role>
      <ShortName>Accrued Expenses and Other Current Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>100160 - Disclosure - Debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureDebt</Role>
      <ShortName>Debt</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>100170 - Disclosure - Fair Value Measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureFairValueMeasurements</Role>
      <ShortName>Fair Value Measurements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>100180 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureCommitmentsAndContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>100190 - Disclosure - Operating Leases</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureOperatingLeases</Role>
      <ShortName>Operating Leases</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>100200 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureIncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>100210 - Disclosure - Net Income (Loss) Per Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/DisclosureNetIncomeLossPerShare</Role>
      <ShortName>Net Income (Loss) Per Share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>100220 - Disclosure - Equity-Based Compensation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureEquityBasedCompensation</Role>
      <ShortName>Equity-Based Compensation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>100230 - Disclosure - Related Party Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureRelatedPartyTransactions</Role>
      <ShortName>Related Party Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>100240 - Disclosure - Barter Arrangement</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureBarterArrangement</Role>
      <ShortName>Barter Arrangement</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>100250 - Disclosure - Summary of Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPolicies</ParentRole>
      <Position>24</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>100260 - Disclosure - Summary of Significant Accounting Policies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesTables</Role>
      <ShortName>Summary of Significant Accounting Policies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPolicies</ParentRole>
      <Position>25</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>100270 - Disclosure - Revenues (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureRevenuesTables</Role>
      <ShortName>Revenues (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureRevenues</ParentRole>
      <Position>26</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>100280 - Disclosure - Prepaid Expenses and Other Current Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosurePrepaidExpensesAndOtherCurrentAssetsTables</Role>
      <ShortName>Prepaid Expenses and Other Current Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosurePrepaidExpensesAndOtherCurrentAssets</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>100290 - Disclosure - Goodwill and Other Intangible Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsTables</Role>
      <ShortName>Goodwill and Other Intangible Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssets</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>100300 - Disclosure - Property and Equipment (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosurePropertyAndEquipmentTables</Role>
      <ShortName>Property and Equipment (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosurePropertyAndEquipment</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>100310 - Disclosure - Accrued Expenses and Other Current Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureAccruedExpensesAndOtherCurrentLiabilitiesTables</Role>
      <ShortName>Accrued Expenses and Other Current Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureAccruedExpensesAndOtherCurrentLiabilities</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>100320 - Disclosure - Debt (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureDebtTables</Role>
      <ShortName>Debt (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureDebt</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>100330 - Disclosure - Fair Value Measurements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureFairValueMeasurementsTables</Role>
      <ShortName>Fair Value Measurements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureFairValueMeasurements</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>100340 - Disclosure - Operating Leases (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureOperatingLeasesTables</Role>
      <ShortName>Operating Leases (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureOperatingLeases</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>100350 - Disclosure - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureIncomeTaxesTables</Role>
      <ShortName>Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureIncomeTaxes</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>100360 - Disclosure - Net Income (Loss) Per Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/DisclosureNetIncomeLossPerShareTables</Role>
      <ShortName>Net Income (Loss) Per Share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/DisclosureNetIncomeLossPerShare</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>100370 - Disclosure - Equity-Based Compensation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureEquityBasedCompensationTables</Role>
      <ShortName>Equity-Based Compensation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureEquityBasedCompensation</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>100380 - Disclosure - General - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureGeneralAdditionalInformationDetail</Role>
      <ShortName>General - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>100390 - Disclosure - Summary of Significant Accounting Policies - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail</Role>
      <ShortName>Summary of Significant Accounting Policies - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>38</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>100400 - Disclosure - Summary of Significant Accounting Policies - Summary of Supplemental Cash Flow Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesSummaryOfSupplementalCashFlowInformationDetail</Role>
      <ShortName>Summary of Significant Accounting Policies - Summary of Supplemental Cash Flow Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>100410 - Disclosure - Summary of Significant Accounting Policies - Estimated Useful Lives of Property and Equipment Asset (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesEstimatedUsefulLivesOfPropertyAndEquipmentAssetDetail</Role>
      <ShortName>Summary of Significant Accounting Policies - Estimated Useful Lives of Property and Equipment Asset (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>100430 - Disclosure - Revenues - Schedule of Revenues Disaggregated by Revenue Source (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureRevenuesScheduleOfRevenuesDisaggregatedByRevenueSourceDetail</Role>
      <ShortName>Revenues - Schedule of Revenues Disaggregated by Revenue Source (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>100440 - Disclosure - Revenues - Schedule of Contract Liabilities (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureRevenuesScheduleOfContractLiabilitiesDetail</Role>
      <ShortName>Revenues - Schedule of Contract Liabilities (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>100450 - Disclosure - Revenues - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureRevenuesAdditionalInformationDetail</Role>
      <ShortName>Revenues - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>100460 - Disclosure - Prepaid Expenses and Other Current Assets - Schedule of Prepaid Expenses and Other Current Assets (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosurePrepaidExpensesAndOtherCurrentAssetsScheduleOfPrepaidExpensesAndOtherCurrentAssetsDetail</Role>
      <ShortName>Prepaid Expenses and Other Current Assets - Schedule of Prepaid Expenses and Other Current Assets (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>100470 - Disclosure - Goodwill and Other Intangible Assets - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsAdditionalInformationDetail</Role>
      <ShortName>Goodwill and Other Intangible Assets - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>100480 - Disclosure - Goodwill and Other Intangible Assets - Summary of Other Intangible Assets (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfOtherIntangibleAssetsDetail</Role>
      <ShortName>Goodwill and Other Intangible Assets - Summary of Other Intangible Assets (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>100490 - Disclosure - Goodwill and Other Intangible Assets - Summary of Estimated Useful Lives of Intangible Assets (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedUsefulLivesOfIntangibleAssetsDetail</Role>
      <ShortName>Goodwill and Other Intangible Assets - Summary of Estimated Useful Lives of Intangible Assets (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>100500 - Disclosure - Goodwill and Other Intangible Assets - Summary of Estimated Amortization Expense (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureGoodwillAndOtherIntangibleAssetsSummaryOfEstimatedAmortizationExpenseDetail</Role>
      <ShortName>Goodwill and Other Intangible Assets - Summary of Estimated Amortization Expense (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>100510 - Disclosure - Property and Equipment - Schedule of Property and Equipment (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosurePropertyAndEquipmentScheduleOfPropertyAndEquipmentDetail</Role>
      <ShortName>Property and Equipment - Schedule of Property and Equipment (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>100530 - Disclosure - Property and Equipment - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosurePropertyAndEquipmentAdditionalInformationDetail</Role>
      <ShortName>Property and Equipment - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>50</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>100540 - Disclosure - Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureAccruedExpensesAndOtherCurrentLiabilitiesScheduleOfAccruedExpensesAndOtherCurrentLiabilitiesDetail</Role>
      <ShortName>Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>100550 - Disclosure - Accrued Expenses and Other Current Liabilities - Schedule of Changes in Accrued Returns Reserve (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureAccruedExpensesAndOtherCurrentLiabilitiesScheduleOfChangesInAccruedReturnsReserveDetail</Role>
      <ShortName>Accrued Expenses and Other Current Liabilities - Schedule of Changes in Accrued Returns Reserve (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>100570 - Disclosure - Debt - Components of Outstanding Long term debt (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureDebtComponentsOfOutstandingLongTermDebtDetail</Role>
      <ShortName>Debt - Components of Outstanding Long term debt (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>100580 - Disclosure - Debt - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail</Role>
      <ShortName>Debt - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>100590 - Disclosure - Debt - Existing Term Loan (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/DisclosureDebtExistingTermLoanDetail</Role>
      <ShortName>Debt - Existing Term Loan (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>100600 - Disclosure - Debt - Priming Loan (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureDebtPrimingLoanDetail</Role>
      <ShortName>Debt - Priming Loan (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>100610 - Disclosure - Debt - Subordinated Facility (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureDebtSubordinatedFacilityDetail</Role>
      <ShortName>Debt - Subordinated Facility (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>100620 - Disclosure - Debt - Asset-Based Revolving Credit Agreement (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureDebtAssetBasedRevolvingCreditAgreementDetail</Role>
      <ShortName>Debt - Asset-Based Revolving Credit Agreement (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>100630 - Disclosure - Debt - Letters of Credit (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureDebtLettersOfCreditDetail</Role>
      <ShortName>Debt - Letters of Credit (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>100640 - Disclosure - Debt - Schedule of Minimum Future Principal Amounts Payable Under Outstanding Long-term Debt (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureDebtScheduleOfMinimumFuturePrincipalAmountsPayableUnderOutstandingLongTermDebtDetail</Role>
      <ShortName>Debt - Schedule of Minimum Future Principal Amounts Payable Under Outstanding Long-term Debt (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>100650 - Disclosure - Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureFairValueMeasurementsScheduleOfAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasisDetails</Role>
      <ShortName>Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>100660 - Disclosure - Commitments and Contingencies - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail</Role>
      <ShortName>Commitments and Contingencies - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>100670 - Disclosure - Operating Leases - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureOperatingLeasesAdditionalInformationDetail</Role>
      <ShortName>Operating Leases - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>100680 - Disclosure - Operating Leases - Components of Lease Expense (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureOperatingLeasesComponentsOfLeaseExpenseDetail</Role>
      <ShortName>Operating Leases - Components of Lease Expense (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>100690 - Disclosure - Operating Leases - Schedule of Lease Terms and Discount Rate (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureOperatingLeasesScheduleOfLeaseTermsAndDiscountRateDetail</Role>
      <ShortName>Operating Leases - Schedule of Lease Terms and Discount Rate (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>100700 - Disclosure - Operating Leases - Schedule of Maturities of Lease Liabilities (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureOperatingLeasesScheduleOfMaturitiesOfLeaseLiabilitiesDetail</Role>
      <ShortName>Operating Leases - Schedule of Maturities of Lease Liabilities (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>100710 - Disclosure - Operating Leases - Schedule of Maturities of Lease Liabilities (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureOperatingLeasesScheduleOfMaturitiesOfLeaseLiabilitiesParentheticalDetail</Role>
      <ShortName>Operating Leases - Schedule of Maturities of Lease Liabilities (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>100720 - Disclosure - Income Taxes - Schedule of Provision (Benefit) for Income Taxes (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfProvisionBenefitForIncomeTaxesDetail</Role>
      <ShortName>Income Taxes - Schedule of Provision (Benefit) for Income Taxes (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>100730 - Disclosure - Income Taxes - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail</Role>
      <ShortName>Income Taxes - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>100740 - Disclosure - Income Taxes - Schedule of Reconciliation of Statutory Federal Income Tax Rate (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureIncomeTaxesScheduleOfReconciliationOfStatutoryFederalIncomeTaxRateDetail</Role>
      <ShortName>Income Taxes - Schedule of Reconciliation of Statutory Federal Income Tax Rate (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>100750 - Disclosure - Income Taxes - Components of Deferred Income Tax Assets and (Liabilities) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureIncomeTaxesComponentsOfDeferredIncomeTaxAssetsAndLiabilitiesDetail</Role>
      <ShortName>Income Taxes - Components of Deferred Income Tax Assets and (Liabilities) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>100760 - Disclosure - Income Taxes - Summary of Changes in Unrecognized Income Tax Benefits (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureIncomeTaxesSummaryOfChangesInUnrecognizedIncomeTaxBenefitsDetail</Role>
      <ShortName>Income Taxes - Summary of Changes in Unrecognized Income Tax Benefits (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>100780 - Disclosure - Net Income (Loss) Per Share - Computation of Basic and Diluted Net Income (Loss) Per Common Share Attributable to Common Shareholders (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/DisclosureNetIncomeLossPerShareComputationOfBasicAndDilutedNetIncomeLossPerCommonShareAttributableToCommonShareholdersDetail</Role>
      <ShortName>Net Income (Loss) Per Share - Computation of Basic and Diluted Net Income (Loss) Per Common Share Attributable to Common Shareholders (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/DisclosureNetIncomeLossPerShareTables</ParentRole>
      <Position>73</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>100790 - Disclosure - Net Income (Loss) Per Share - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/DisclosureNetIncomeLossPerShareAdditionalInformationDetail</Role>
      <ShortName>Net Income (Loss) Per Share - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.jjill.com/20230128/taxonomy/role/DisclosureNetIncomeLossPerShareTables</ParentRole>
      <Position>74</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>100800 - Disclosure - Equity-Based Compensation - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureEquityBasedCompensationAdditionalInformationDetail</Role>
      <ShortName>Equity-Based Compensation - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>100810 - Disclosure - Equity-Based Compensation - Summary of RSAs and RSUs Award Activity (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/DisclosureEquitybasedCompensationSummaryOfRsasAndRsusAwardActivityDetail</Role>
      <ShortName>Equity-Based Compensation - Summary of RSAs and RSUs Award Activity (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>100820 - Disclosure - Equity-Based Compensation - Summary of Stock Options Award Activity (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/DisclosureEquitybasedCompensationSummaryOfStockOptionsAwardActivityDetail</Role>
      <ShortName>Equity-Based Compensation - Summary of Stock Options Award Activity (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>100840 - Disclosure - Related Party Transactions - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureRelatedPartyTransactionsAdditionalInformationDetail</Role>
      <ShortName>Related Party Transactions - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="jill-20230128.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>100850 - Disclosure - Barter Arrangement - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.jjill.com/20230128/taxonomy/role/Role_DisclosureBarterArrangementAdditionalInformationDetail</Role>
      <ShortName>Barter Arrangement - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <Logs>
    <Log type="Warning">[dq-0542-Deprecated-Concept] Concept DueToRelatedPartiesNoncurrent in us-gaap/2022 used in 2 facts was deprecated in us-gaap/2023 as of 2023 and should not be used. jill-20230128.htm 3634, 3638</Log>
    <Log type="Warning">[dq-0542-Deprecated-Concept] Concept InterestExpenseRelatedParty in us-gaap/2022 used in 5 facts was deprecated in us-gaap/2023 as of 2023 and should not be used. jill-20230128.htm 3973, 3977, 3981, 8596, 8597</Log>
    <Log type="Warning">[dq-0542-Deprecated-Concept] Concept PropertyPlantAndEquipmentEstimatedUsefulLives in us-gaap/2022 used in 1 facts was deprecated in us-gaap/2023 as of 2023 and should not be used. jill-20230128.htm 5530</Log>
    <Log type="Warning">[dq-0542-Deprecated-Concept] Concept LondonInterbankOfferedRateLIBORMember in us-gaap/2022 used in 4 facts was deprecated in us-gaap/2023 as of 2023 and should not be used. jill-20230128.htm 6816, 6817</Log>
    <Log type="Warning">[dq-0542-Deprecated-Concept] Concept RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty in us-gaap/2022 used in 1 facts was deprecated in us-gaap/2023 as of 2023 and should not be used. jill-20230128.htm 8597</Log>
    <Log type="Warning">[ix-0514-Hidden-Fact-Eligible-For-Transform] WARN: 2 fact(s) appearing in ix:hidden were eligible for transformation: dei:CurrentFiscalYearEndDate, us-gaap:LesseeOperatingLeaseRenewalTerm -  jill-20230128.htm 8</Log>
    <Log type="Warning">[dqc-0033-Document-Period-End-Date-Context] The ending date of 2021-01-30 used for AuditorFirmId must be the same as the Document Period End Date, 2023-01-28. The properties of this AuditorFirmId fact are Context: C_1b75f6cc-ba08-4828-a549-73696f0be07f, Unit: (none), Rule Element Id: 2. jill-20230128.htm 176</Log>
    <Log type="Warning">[dqc-0033-Document-Period-End-Date-Context] The ending date of 2022-01-29 used for AuditorFirmId must be the same as the Document Period End Date, 2023-01-28. The properties of this AuditorFirmId fact are Context: C_75a51e5c-7b54-4275-818e-a57979191f3c, Unit: (none), Rule Element Id: 2. jill-20230128.htm 166</Log>
    <Log type="Warning">[dqc-0033-Document-Period-End-Date-Context] The ending date of 2021-01-30 used for AuditorLocation must be the same as the Document Period End Date, 2023-01-28. The properties of this AuditorLocation fact are Context: C_1b75f6cc-ba08-4828-a549-73696f0be07f, Unit: (none), Rule Element Id: 2. jill-20230128.htm 182</Log>
    <Log type="Warning">[dqc-0033-Document-Period-End-Date-Context] The ending date of 2022-01-29 used for AuditorLocation must be the same as the Document Period End Date, 2023-01-28. The properties of this AuditorLocation fact are Context: C_75a51e5c-7b54-4275-818e-a57979191f3c, Unit: (none), Rule Element Id: 2. jill-20230128.htm 172</Log>
    <Log type="Warning">[dqc-0033-Document-Period-End-Date-Context] The ending date of 2022-01-29 used for AuditorName must be the same as the Document Period End Date, 2023-01-28. The properties of this AuditorName fact are Context: C_75a51e5c-7b54-4275-818e-a57979191f3c, Unit: (none), Rule Element Id: 2. jill-20230128.htm 169</Log>
    <Log type="Warning">[dqc-0033-Document-Period-End-Date-Context] The ending date of 2021-01-30 used for AuditorName must be the same as the Document Period End Date, 2023-01-28. The properties of this AuditorName fact are Context: C_1b75f6cc-ba08-4828-a549-73696f0be07f, Unit: (none), Rule Element Id: 2. jill-20230128.htm 179</Log>
  </Logs>
  <InputFiles>
    <File doctype="10-K" original="jill-20230128.htm">jill-20230128.htm</File>
    <File>jill-20230128.xsd</File>
    <File>jill-20230128_cal.xml</File>
    <File>jill-20230128_def.xml</File>
    <File>jill-20230128_lab.xml</File>
    <File>jill-20230128_pre.xml</File>
    <File>jill-ex23_1.htm</File>
    <File>jill-ex23_2.htm</File>
    <File>jill-ex31_1.htm</File>
    <File>jill-ex31_2.htm</File>
    <File>jill-ex32_1.htm</File>
    <File>jill-ex32_2.htm</File>
  </InputFiles>
  <SupplementalFiles>
    <File>img117020820_0.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="735">http://fasb.org/us-gaap/2022</BaseTaxonomy>
    <BaseTaxonomy items="43">http://xbrl.sec.gov/dei/2022</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
