<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.26.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>442</ContextCount>
  <ElementCount>451</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>170</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>15</UnitCount>
  <MyReports>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>000100 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/DocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>010000 - Statement - Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/ConsolidatedBalanceSheets</Role>
      <ShortName>Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>010100 - Statement - Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/ConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Consolidated Balance Sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>020000 - Statement - Consolidated Statements of Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/ConsolidatedStatementsOfIncome</Role>
      <ShortName>Consolidated Statements of Income</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>030000 - Statement - Consolidated Statements of Stockholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/ConsolidatedStatementsOfStockholdersEquity</Role>
      <ShortName>Consolidated Statements of Stockholders' Equity</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>030100 - Statement - Consolidated Statements of Stockholders' Equity (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/ConsolidatedStatementsOfStockholdersEquityParenthetical</Role>
      <ShortName>Consolidated Statements of Stockholders' Equity (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>040000 - Statement - Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/ConsolidatedStatementsOfCashFlows</Role>
      <ShortName>Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>060100 - Disclosure - Basis of Presentation and General Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/BasisOfPresentationAndGeneralInformation</Role>
      <ShortName>Basis of Presentation and General Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>060200 - Disclosure - Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/SignificantAccountingPolicies</Role>
      <ShortName>Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>060300 - Disclosure - Transactions with Related Parties</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/TransactionsWithRelatedParties</Role>
      <ShortName>Transactions with Related Parties</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>060400 - Disclosure - Cash and Cash Equivalents and Restricted Cash</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/CashAndCashEquivalentsAndRestrictedCash</Role>
      <ShortName>Cash and Cash Equivalents and Restricted Cash</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>060500 - Disclosure - Inventories</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/Inventories</Role>
      <ShortName>Inventories</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>060600 - Disclosure - Vessels, Net</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/VesselsNet</Role>
      <ShortName>Vessels, Net</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>060700 - Disclosure - Finance Lease, Right-of-use Assets and Finance Lease Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/FinanceLeaseRightofuseAssetsAndFinanceLeaseLiabilities</Role>
      <ShortName>Finance Lease, Right-of-use Assets and Finance Lease Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>060800 - Disclosure - Long-Term Debt and Other Financial Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilities</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>060900 - Disclosure - Financial Instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/FinancialInstruments</Role>
      <ShortName>Financial Instruments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>061000 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/CommitmentsAndContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>061100 - Disclosure - Capital Structure</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/CapitalStructure</Role>
      <ShortName>Capital Structure</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>061200 - Disclosure - Vessel Revenue and Voyage Expenses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/VesselRevenueAndVoyageExpenses</Role>
      <ShortName>Vessel Revenue and Voyage Expenses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>061300 - Disclosure - Interest and Finance Costs</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/InterestAndFinanceCosts</Role>
      <ShortName>Interest and Finance Costs</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>061400 - Disclosure - Earnings per Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/EarningsPerShare</Role>
      <ShortName>Earnings per Share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>061500 - Disclosure - Equity Incentive Plan</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/EquityIncentivePlan</Role>
      <ShortName>Equity Incentive Plan</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>061600 - Disclosure - Subsequent Events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/SubsequentEvents</Role>
      <ShortName>Subsequent Events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>061700 - Disclosure - Insider Trading Policies and Procedures</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/InsiderTradingPoliciesAndProcedures</Role>
      <ShortName>Insider Trading Policies and Procedures</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>061800 - Disclosure - Cybersecurity Risk Management and Strategy Disclosure</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/CybersecurityRiskManagementAndStrategyDisclosure</Role>
      <ShortName>Cybersecurity Risk Management and Strategy Disclosure</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>070200 - Disclosure - Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/SignificantAccountingPoliciesPolicies</Role>
      <ShortName>Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/SignificantAccountingPolicies</ParentRole>
      <Position>26</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>080100 - Disclosure - Basis of Presentation and General Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/BasisOfPresentationAndGeneralInformationTables</Role>
      <ShortName>Basis of Presentation and General Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/BasisOfPresentationAndGeneralInformation</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>080400 - Disclosure - Cash and Cash Equivalents and Restricted Cash (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/CashAndCashEquivalentsAndRestrictedCashTables</Role>
      <ShortName>Cash and Cash Equivalents and Restricted Cash (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/CashAndCashEquivalentsAndRestrictedCash</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>080600 - Disclosure - Vessels, Net (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/VesselsNetTables</Role>
      <ShortName>Vessels, Net (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/VesselsNet</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>080800 - Disclosure - Long-Term Debt and Other Financial Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesTables</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilities</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>081000 - Disclosure - Commitments and Contingencies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/CommitmentsAndContingenciesTables</Role>
      <ShortName>Commitments and Contingencies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/CommitmentsAndContingencies</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>081200 - Disclosure - Vessel Revenue and Voyage Expenses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/VesselRevenueAndVoyageExpensesTables</Role>
      <ShortName>Vessel Revenue and Voyage Expenses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/VesselRevenueAndVoyageExpenses</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>081300 - Disclosure - Interest and Finance Costs (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/InterestAndFinanceCostsTables</Role>
      <ShortName>Interest and Finance Costs (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/InterestAndFinanceCosts</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>081400 - Disclosure - Earnings per Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/EarningsPerShareTables</Role>
      <ShortName>Earnings per Share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/EarningsPerShare</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>081500 - Disclosure - Equity Incentive Plan (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/EquityIncentivePlanTables</Role>
      <ShortName>Equity Incentive Plan (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/EquityIncentivePlan</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>090100 - Disclosure - Basis of Presentation and General Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/BasisOfPresentationAndGeneralInformationDetails</Role>
      <ShortName>Basis of Presentation and General Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/BasisOfPresentationAndGeneralInformationTables</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>090200 - Disclosure - Significant Accounting Policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/SignificantAccountingPoliciesDetails</Role>
      <ShortName>Significant Accounting Policies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/SignificantAccountingPoliciesPolicies</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>090304 - Disclosure - Transactions with Related Parties (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/TransactionsWithRelatedPartiesDetails</Role>
      <ShortName>Transactions with Related Parties (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/TransactionsWithRelatedParties</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>090400 - Disclosure - Cash and Cash Equivalents and Restricted Cash (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/CashAndCashEquivalentsAndRestrictedCashDetails</Role>
      <ShortName>Cash and Cash Equivalents and Restricted Cash (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/CashAndCashEquivalentsAndRestrictedCashTables</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>090500 - Disclosure - Inventories (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/InventoriesDetails</Role>
      <ShortName>Inventories (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/Inventories</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>090600 - Disclosure - Vessels, Net, Net Book Value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/VesselsNetNetBookValueDetails</Role>
      <ShortName>Vessels, Net, Net Book Value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>090602 - Disclosure - Vessels, Net, Acquisitions, Advances and Sales (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/VesselsNetAcquisitionsAdvancesAndSalesDetails</Role>
      <ShortName>Vessels, Net, Acquisitions, Advances and Sales (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>090700 - Disclosure - Finance Lease, Right-of-use Assets and Finance Lease Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/FinanceLeaseRightofuseAssetsAndFinanceLeaseLiabilitiesDetails</Role>
      <ShortName>Finance Lease, Right-of-use Assets and Finance Lease Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/FinanceLeaseRightofuseAssetsAndFinanceLeaseLiabilities</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>090800 - Disclosure - Long-Term Debt and Other Financial Liabilities, Summary of Long-Term Debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesSummaryOfLongtermDebtDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Summary of Long-Term Debt (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>090802 - Disclosure - Long-Term Debt and Other Financial Liabilities, February 2025 Piraeus Bank Loan Facility (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesFebruary2025PiraeusBankLoanFacilityDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, February 2025 Piraeus Bank Loan Facility (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>090804 - Disclosure - Long-Term Debt and Other Financial Liabilities, December 2025 Danish Ship Finance Loan Facility (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesDecember2025DanishShipFinanceLoanFacilityDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, December 2025 Danish Ship Finance Loan Facility (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>090806 - Disclosure - Long-Term Debt and Other Financial Liabilities, June 2022 Alpha Bank Loan Facility (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesJune2022AlphaBankLoanFacilityDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, June 2022 Alpha Bank Loan Facility (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>090810 - Disclosure - Long-Term Debt and Other Financial Liabilities, October 2024 Alpha Bank Loan Facility (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesOctober2024AlphaBankLoanFacilityDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, October 2024 Alpha Bank Loan Facility (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>090812 - Disclosure - Long-Term Debt and Other Financial Liabilities, August 2021 Alpha Bank Loan Facility (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesAugust2021AlphaBankLoanFacilityDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, August 2021 Alpha Bank Loan Facility (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>090814 - Disclosure - Long-Term Debt and Other Financial Liabilities, Sinopac Loan Facility (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesSinopacLoanFacilityDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Sinopac Loan Facility (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>50</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>090816 - Disclosure - Long-Term Debt and Other Financial Liabilities, June 2022 Piraeus Bank Loan Facility (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesJune2022PiraeusBankLoanFacilityDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, June 2022 Piraeus Bank Loan Facility (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>090818 - Disclosure - Long-Term Debt and Other Financial Liabilities, October 2022 Danish Ship Finance Loan Facility (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesOctober2022DanishShipFinanceLoanFacilityDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, October 2022 Danish Ship Finance Loan Facility (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>090820 - Disclosure - Long-Term Debt and Other Financial Liabilities, December 2022 Alpha Bank Loan Facility (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesDecember2022AlphaBankLoanFacilityDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, December 2022 Alpha Bank Loan Facility (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>090822 - Disclosure - Long-Term Debt and Other Financial Liabilities, Huarong Friendship Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesHuarongFriendshipSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Huarong Friendship Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>090824 - Disclosure - Long-Term Debt and Other Financial Liabilities, Huarong Squireship Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesHuarongSquireshipSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Huarong Squireship Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>090826 - Disclosure - Long-Term Debt and Other Financial Liabilities, Kowa Blueship Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesKowaBlueshipSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Kowa Blueship Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>090828 - Disclosure - Long-Term Debt and Other Financial Liabilities, Huarong Hellasship Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesHuarongHellasshipSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Huarong Hellasship Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>090830 - Disclosure - Long-Term Debt and Other Financial Liabilities, Huarong Iconship Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesHuarongIconshipSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Huarong Iconship Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>090832 - Disclosure - Long-Term Debt and Other Financial Liabilities, Huarong Patriotship Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesHuarongPatriotshipSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Huarong Patriotship Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>090834 - Disclosure - Long-Term Debt and Other Financial Liabilities, Evahline Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesEvahlineSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Evahline Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>090836 - Disclosure - Long-Term Debt and Other Financial Liabilities, Village Seven Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesVillageSevenSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Village Seven Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>090838 - Disclosure - Long-Term Debt and Other Financial Liabilities, Hinode Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesHinodeSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Hinode Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>090840 - Disclosure - Long-Term Debt and Other Financial Liabilities, Flagship Cargill Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesFlagshipCargillSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Flagship Cargill Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>090842 - Disclosure - Long-Term Debt and Other Financial Liabilities, CMBFL Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesCmbflSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, CMBFL Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>090844 - Disclosure - Long-Term Debt and Other Financial Liabilities, AVIC Hellasship Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesAvicHellasshipSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, AVIC Hellasship Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>090848 - Disclosure - Long-Term Debt and Other Financial Liabilities, AVIC Iconship Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesAvicIconshipSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, AVIC Iconship Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>090850 - Disclosure - Long-Term Debt and Other Financial Liabilities, AVIC Patriotship Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesAvicPatriotshipSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, AVIC Patriotship Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>090852 - Disclosure - Long-Term Debt and Other Financial Liabilities, Chugoku Bank Sale and Leaseback (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesChugokuBankSaleAndLeasebackDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Chugoku Bank Sale and Leaseback (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>090858 - Disclosure - Long-Term Debt and Other Financial Liabilities, Collateral (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesCollateralDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Collateral (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>090860 - Disclosure - Long-Term Debt and Other Financial Liabilities, Annual Principal Payments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/LongtermDebtAndOtherFinancialLiabilitiesAnnualPrincipalPaymentsDetails</Role>
      <ShortName>Long-Term Debt and Other Financial Liabilities, Annual Principal Payments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>091000 - Disclosure - Commitments and Contingencies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/CommitmentsAndContingenciesDetails</Role>
      <ShortName>Commitments and Contingencies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/CommitmentsAndContingenciesTables</ParentRole>
      <Position>71</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>091100 - Disclosure - Capital Structure, Preferred Stock (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/CapitalStructurePreferredStockDetails</Role>
      <ShortName>Capital Structure, Preferred Stock (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>091104 - Disclosure - Capital Structure, Common Stock (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/CapitalStructureCommonStockDetails</Role>
      <ShortName>Capital Structure, Common Stock (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>091110 - Disclosure - Capital Structure, Warrants (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/CapitalStructureWarrantsDetails</Role>
      <ShortName>Capital Structure, Warrants (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>091200 - Disclosure - Vessel Revenue and Voyage Expenses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/VesselRevenueAndVoyageExpensesDetails</Role>
      <ShortName>Vessel Revenue and Voyage Expenses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/VesselRevenueAndVoyageExpensesTables</ParentRole>
      <Position>75</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>091300 - Disclosure - Interest and Finance Costs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/InterestAndFinanceCostsDetails</Role>
      <ShortName>Interest and Finance Costs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/InterestAndFinanceCostsTables</ParentRole>
      <Position>76</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>091400 - Disclosure - Earnings per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/EarningsPerShareDetails</Role>
      <ShortName>Earnings per Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/EarningsPerShareTables</ParentRole>
      <Position>77</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>091500 - Disclosure - Equity Incentive Plan (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/EquityIncentivePlanDetails</Role>
      <ShortName>Equity Incentive Plan (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/EquityIncentivePlanTables</ParentRole>
      <Position>78</Position>
    </Report>
    <Report instance="ef20060628_20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>091600 - Disclosure - Subsequent Events (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://seanergymaritime.com/role/SubsequentEventsDetails</Role>
      <ShortName>Subsequent Events (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://seanergymaritime.com/role/SubsequentEvents</ParentRole>
      <Position>79</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" isDefinitelyFs="true" isUsgaap="true" original="ef20060628_20f.htm">ef20060628_20f.htm</File>
    <File>ship-20251231.xsd</File>
    <File>ship-20251231_cal.xml</File>
    <File>ship-20251231_def.xml</File>
    <File>ship-20251231_lab.xml</File>
    <File>ship-20251231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy items="3">http://fasb.org/srt/2025</BaseTaxonomy>
    <BaseTaxonomy items="1077">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="16">http://xbrl.sec.gov/cyd/2025</BaseTaxonomy>
    <BaseTaxonomy items="79">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="1">http://xbrl.sec.gov/ecd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
