<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.21.2</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>693</ContextCount>
  <ElementCount>490</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>101</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>6</UnitCount>
  <MyReports>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0001001 - Document - Cover Page</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/CoverPage</Role>
      <ShortName>Cover Page</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>1001002 - Statement - Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/ConsolidatedBalanceSheets</Role>
      <ShortName>Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>1002003 - Statement - Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/ConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Consolidated Balance Sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>1003004 - Statement - Consolidated Statements of Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/ConsolidatedStatementsofIncome</Role>
      <ShortName>Consolidated Statements of Income</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>1004005 - Statement - Consolidated Statements of Comprehensive Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/ConsolidatedStatementsofComprehensiveIncome</Role>
      <ShortName>Consolidated Statements of Comprehensive Income</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>1005006 - Statement - Consolidated Statements of Shareholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/ConsolidatedStatementsofShareholdersEquity</Role>
      <ShortName>Consolidated Statements of Shareholders' Equity</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>1006007 - Statement - Consolidated Statements of Shareholders' Equity (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/ConsolidatedStatementsofShareholdersEquityParenthetical</Role>
      <ShortName>Consolidated Statements of Shareholders' Equity (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>1007008 - Statement - Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/ConsolidatedStatementsofCashFlows</Role>
      <ShortName>Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>2101101 - Disclosure - Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/BasisofPresentation</Role>
      <ShortName>Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>2104102 - Disclosure - Restrictions on Cash and Cash Equivalents</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/RestrictionsonCashandCashEquivalents</Role>
      <ShortName>Restrictions on Cash and Cash Equivalents</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>2106103 - Disclosure - Investment Securities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/InvestmentSecurities</Role>
      <ShortName>Investment Securities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>2114104 - Disclosure - Loans and Allowance for Credit Losses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLosses</Role>
      <ShortName>Loans and Allowance for Credit Losses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>2128105 - Disclosure - Mortgage Servicing Rights</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/MortgageServicingRights</Role>
      <ShortName>Mortgage Servicing Rights</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>2132106 - Disclosure - Derivative Financial Instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/DerivativeFinancialInstruments</Role>
      <ShortName>Derivative Financial Instruments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>2140107 - Disclosure - Tax Credit Investments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/TaxCreditInvestments</Role>
      <ShortName>Tax Credit Investments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>2143108 - Disclosure - Accumulated Other Comprehensive Income (Loss)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/AccumulatedOtherComprehensiveIncomeLoss</Role>
      <ShortName>Accumulated Other Comprehensive Income (Loss)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>2147109 - Disclosure - Fair Value Measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/FairValueMeasurements</Role>
      <ShortName>Fair Value Measurements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>2154110 - Disclosure - Net Income Per Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/NetIncomePerShare</Role>
      <ShortName>Net Income Per Share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>2157111 - Disclosure - Stock-Based Compensation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/StockBasedCompensation</Role>
      <ShortName>Stock-Based Compensation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>2161112 - Disclosure - Employee Benefit Plans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/EmployeeBenefitPlans</Role>
      <ShortName>Employee Benefit Plans</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>2164113 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/CommitmentsandContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>2168114 - Disclosure - Long-Term Borrowings</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LongTermBorrowings</Role>
      <ShortName>Long-Term Borrowings</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>2202201 - Disclosure - Basis of Presentation (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/BasisofPresentationPolicies</Role>
      <ShortName>Basis of Presentation (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>2307301 - Disclosure - Investment Securities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/InvestmentSecuritiesTables</Role>
      <ShortName>Investment Securities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.fult.com/role/InvestmentSecurities</ParentRole>
      <Position>24</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>2315302 - Disclosure - Loans and Allowance for Credit Losses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLossesTables</Role>
      <ShortName>Loans and Allowance for Credit Losses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.fult.com/role/LoansandAllowanceforCreditLosses</ParentRole>
      <Position>25</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>2329303 - Disclosure - Mortgage Servicing Rights (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/MortgageServicingRightsTables</Role>
      <ShortName>Mortgage Servicing Rights (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.fult.com/role/MortgageServicingRights</ParentRole>
      <Position>26</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>2333304 - Disclosure - Derivative Financial Instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/DerivativeFinancialInstrumentsTables</Role>
      <ShortName>Derivative Financial Instruments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.fult.com/role/DerivativeFinancialInstruments</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>2341305 - Disclosure - Tax Credit Investments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/TaxCreditInvestmentsTables</Role>
      <ShortName>Tax Credit Investments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.fult.com/role/TaxCreditInvestments</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>2344306 - Disclosure - Accumulated Other Comprehensive Income (Loss) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/AccumulatedOtherComprehensiveIncomeLossTables</Role>
      <ShortName>Accumulated Other Comprehensive Income (Loss) (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.fult.com/role/AccumulatedOtherComprehensiveIncomeLoss</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>2348307 - Disclosure - Fair Value Measurements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/FairValueMeasurementsTables</Role>
      <ShortName>Fair Value Measurements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.fult.com/role/FairValueMeasurements</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>2355308 - Disclosure - Net Income Per Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/NetIncomePerShareTables</Role>
      <ShortName>Net Income Per Share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.fult.com/role/NetIncomePerShare</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>2358309 - Disclosure - Stock-Based Compensation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/StockBasedCompensationTables</Role>
      <ShortName>Stock-Based Compensation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.fult.com/role/StockBasedCompensation</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>2362310 - Disclosure - Employee Benefit Plans (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/EmployeeBenefitPlansTables</Role>
      <ShortName>Employee Benefit Plans (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.fult.com/role/EmployeeBenefitPlans</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>2365311 - Disclosure - Commitments and Contingencies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/CommitmentsandContingenciesTables</Role>
      <ShortName>Commitments and Contingencies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.fult.com/role/CommitmentsandContingencies</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>2403401 - Disclosure - Basis of Presentation Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/BasisofPresentationNarrativeDetails</Role>
      <ShortName>Basis of Presentation Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>2405402 - Disclosure - Restrictions on Cash and Cash Equivalents (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/RestrictionsonCashandCashEquivalentsDetails</Role>
      <ShortName>Restrictions on Cash and Cash Equivalents (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.fult.com/role/RestrictionsonCashandCashEquivalents</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>2408403 - Disclosure - Investment Securities Schedule of Amortized Cost and Fair Values of Investment Securities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/InvestmentSecuritiesScheduleofAmortizedCostandFairValuesofInvestmentSecuritiesDetails</Role>
      <ShortName>Investment Securities Schedule of Amortized Cost and Fair Values of Investment Securities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>2409404 - Disclosure - Investment Securities Schedule of Amortized Cost and Fair Values of Debt Securities by Contractual Maturities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/InvestmentSecuritiesScheduleofAmortizedCostandFairValuesofDebtSecuritiesbyContractualMaturitiesDetails</Role>
      <ShortName>Investment Securities Schedule of Amortized Cost and Fair Values of Debt Securities by Contractual Maturities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>38</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>2410405 - Disclosure - Investment Securities Summary of Gains and Losses from Equity and Debt Securities, and Losses from Other-than-Temporary Impairment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/InvestmentSecuritiesSummaryofGainsandLossesfromEquityandDebtSecuritiesandLossesfromOtherthanTemporaryImpairmentDetails</Role>
      <ShortName>Investment Securities Summary of Gains and Losses from Equity and Debt Securities, and Losses from Other-than-Temporary Impairment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>2411406 - Disclosure - Investment Securities Gross Unrealized Losses and Fair Values of Investments by Category and Length of Time in a Continuous Unrealized Loss Position (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/InvestmentSecuritiesGrossUnrealizedLossesandFairValuesofInvestmentsbyCategoryandLengthofTimeinaContinuousUnrealizedLossPositionDetails</Role>
      <ShortName>Investment Securities Gross Unrealized Losses and Fair Values of Investments by Category and Length of Time in a Continuous Unrealized Loss Position (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>2412407 - Disclosure - Investment Securities Summary of Amortized Cost and Fair Values of Corporate Debt Securities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/InvestmentSecuritiesSummaryofAmortizedCostandFairValuesofCorporateDebtSecuritiesDetails</Role>
      <ShortName>Investment Securities Summary of Amortized Cost and Fair Values of Corporate Debt Securities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>2413408 - Disclosure - Investment Securities Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/InvestmentSecuritiesNarrativeDetails</Role>
      <ShortName>Investment Securities Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>2416409 - Disclosure - Loans and Allowance for Credit Losses Summary Of Gross Loans (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLossesSummaryOfGrossLoansDetails</Role>
      <ShortName>Loans and Allowance for Credit Losses Summary Of Gross Loans (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>2417410 - Disclosure - Loans and Allowance for Credit Losses Allowance for Credit Losses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLossesAllowanceforCreditLossesDetails</Role>
      <ShortName>Loans and Allowance for Credit Losses Allowance for Credit Losses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>2418411 - Disclosure - Loans and Allowance for Credit Losses Activity in the Allowance for Credit Losses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLossesActivityintheAllowanceforCreditLossesDetails</Role>
      <ShortName>Loans and Allowance for Credit Losses Activity in the Allowance for Credit Losses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>2419412 - Disclosure - Loans and Allowance for Credit Losses Allowance for Loan Losses by Portfolio Segment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLossesAllowanceforLoanLossesbyPortfolioSegmentDetails</Role>
      <ShortName>Loans and Allowance for Credit Losses Allowance for Loan Losses by Portfolio Segment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>2420413 - Disclosure - Loans and Allowance for Credit Losses Total Impaired Loans by Class Segments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLossesTotalImpairedLoansbyClassSegmentsDetails</Role>
      <ShortName>Loans and Allowance for Credit Losses Total Impaired Loans by Class Segments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>2421414 - Disclosure - Loans and Allowance for Credit Losses Credit Quality Indicators (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLossesCreditQualityIndicatorsDetails</Role>
      <ShortName>Loans and Allowance for Credit Losses Credit Quality Indicators (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>2422415 - Disclosure - Loans and Allowance for Credit Losses Non-Performing Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLossesNonPerformingAssetsDetails</Role>
      <ShortName>Loans and Allowance for Credit Losses Non-Performing Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>2423416 - Disclosure - Loans and Allowance for Credit Losses Past Due Loan Status and Non-Accrual Loans by Portfolio Segment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLossesPastDueLoanStatusandNonAccrualLoansbyPortfolioSegmentDetails</Role>
      <ShortName>Loans and Allowance for Credit Losses Past Due Loan Status and Non-Accrual Loans by Portfolio Segment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>50</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>2424417 - Disclosure - Loans and Allowance for Credit Losses Loans Modified Under Troubled Debt Restructurings (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLossesLoansModifiedUnderTroubledDebtRestructuringsDetails</Role>
      <ShortName>Loans and Allowance for Credit Losses Loans Modified Under Troubled Debt Restructurings (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>2425418 - Disclosure - Loans and Allowance for Credit Losses Troubled Debt Restructuring Modification (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLossesTroubledDebtRestructuringModificationDetails</Role>
      <ShortName>Loans and Allowance for Credit Losses Troubled Debt Restructuring Modification (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>2426419 - Disclosure - Loans and Allowance for Credit Losses TDRs by Class Segment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLossesTDRsbyClassSegmentDetails</Role>
      <ShortName>Loans and Allowance for Credit Losses TDRs by Class Segment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>2427420 - Disclosure - Loans and Allowance for Credit Losses Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LoansandAllowanceforCreditLossesNarrativeDetails</Role>
      <ShortName>Loans and Allowance for Credit Losses Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>2430421 - Disclosure - Mortgage Servicing Rights Summary of Changes in Mortgage Servicing Rights (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/MortgageServicingRightsSummaryofChangesinMortgageServicingRightsDetails</Role>
      <ShortName>Mortgage Servicing Rights Summary of Changes in Mortgage Servicing Rights (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>2431422 - Disclosure - Mortgage Servicing Rights - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/MortgageServicingRightsNarrativeDetails</Role>
      <ShortName>Mortgage Servicing Rights - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>2434423 - Disclosure - Derivative Financial Instruments Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/DerivativeFinancialInstrumentsNarrativeDetails</Role>
      <ShortName>Derivative Financial Instruments Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>2435424 - Disclosure - Derivative Financial Instruments Notional Amounts and Fair Values of Derivative Financial Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/DerivativeFinancialInstrumentsNotionalAmountsandFairValuesofDerivativeFinancialInstrumentsDetails</Role>
      <ShortName>Derivative Financial Instruments Notional Amounts and Fair Values of Derivative Financial Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>2436425 - Disclosure - Derivative Financial Instruments Summary of Effect of Fair Value and Cash Flow Hedge Accounting on Accumulated Other Comprehensive Income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/DerivativeFinancialInstrumentsSummaryofEffectofFairValueandCashFlowHedgeAccountingonAccumulatedOtherComprehensiveIncomeDetails</Role>
      <ShortName>Derivative Financial Instruments Summary of Effect of Fair Value and Cash Flow Hedge Accounting on Accumulated Other Comprehensive Income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>2437426 - Disclosure - Derivative Financial Instruments Fair Value Gains and Losses on Derivative Financial Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/DerivativeFinancialInstrumentsFairValueGainsandLossesonDerivativeFinancialInstrumentsDetails</Role>
      <ShortName>Derivative Financial Instruments Fair Value Gains and Losses on Derivative Financial Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>2438427 - Disclosure - Derivative Financial Instruments Summary of Mortgage Loans Held For Sale (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/DerivativeFinancialInstrumentsSummaryofMortgageLoansHeldForSaleDetails</Role>
      <ShortName>Derivative Financial Instruments Summary of Mortgage Loans Held For Sale (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>2439428 - Disclosure - Derivative Financial Instruments Offsetting Derivative Assets and Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/DerivativeFinancialInstrumentsOffsettingDerivativeAssetsandLiabilitiesDetails</Role>
      <ShortName>Derivative Financial Instruments Offsetting Derivative Assets and Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>2442429 - Disclosure - Tax Credit Investments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/TaxCreditInvestmentsDetails</Role>
      <ShortName>Tax Credit Investments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.fult.com/role/TaxCreditInvestmentsTables</ParentRole>
      <Position>63</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>2445430 - Disclosure - Accumulated Other Comprehensive Income (Loss) - Changes in Other Comprehensive Income (Loss) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/AccumulatedOtherComprehensiveIncomeLossChangesinOtherComprehensiveIncomeLossDetails</Role>
      <ShortName>Accumulated Other Comprehensive Income (Loss) - Changes in Other Comprehensive Income (Loss) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.fult.com/role/AccumulatedOtherComprehensiveIncomeLossTables</ParentRole>
      <Position>64</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>2446431 - Disclosure - Accumulated Other Comprehensive Income (Loss) - Components of Other Comprehensive Income (Loss) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/AccumulatedOtherComprehensiveIncomeLossComponentsofOtherComprehensiveIncomeLossDetails</Role>
      <ShortName>Accumulated Other Comprehensive Income (Loss) - Components of Other Comprehensive Income (Loss) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.fult.com/role/AccumulatedOtherComprehensiveIncomeLossTables</ParentRole>
      <Position>65</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>2449432 - Disclosure - Fair Value Measurements Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/FairValueMeasurementsAssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetails</Role>
      <ShortName>Fair Value Measurements Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>2450433 - Disclosure - Fair Value Measurements Changes in Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Level 3 Inputs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/FairValueMeasurementsChangesinAssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisUsingLevel3InputsDetails</Role>
      <ShortName>Fair Value Measurements Changes in Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Level 3 Inputs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>2451434 - Disclosure - Fair Value Measurements Assets Measured at Fair Value on a Nonrecurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/FairValueMeasurementsAssetsMeasuredatFairValueonaNonrecurringBasisDetails</Role>
      <ShortName>Fair Value Measurements Assets Measured at Fair Value on a Nonrecurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>2452435 - Disclosure - Fair Value Measurements Details of Book Value and Fair Value of Financial Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/FairValueMeasurementsDetailsofBookValueandFairValueofFinancialInstrumentsDetails</Role>
      <ShortName>Fair Value Measurements Details of Book Value and Fair Value of Financial Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>2453436 - Disclosure - Fair Value Measurements Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/FairValueMeasurementsNarrativeDetails</Role>
      <ShortName>Fair Value Measurements Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>2456437 - Disclosure - Net Income Per Share Reconciliation of Weighted Average Common Shares Outstanding (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/NetIncomePerShareReconciliationofWeightedAverageCommonSharesOutstandingDetails</Role>
      <ShortName>Net Income Per Share Reconciliation of Weighted Average Common Shares Outstanding (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>2459438 - Disclosure - Stock-Based Compensation Compensation Expense and Related Tax Benefits (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/StockBasedCompensationCompensationExpenseandRelatedTaxBenefitsDetails</Role>
      <ShortName>Stock-Based Compensation Compensation Expense and Related Tax Benefits (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>2460439 - Disclosure - Stock-Based Compensation Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/StockBasedCompensationNarrativeDetails</Role>
      <ShortName>Stock-Based Compensation Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>2463440 - Disclosure - Employee Benefit Plans Summary of Pension Plan and Postretirement Plan Net Periodic Benefit Cost (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/EmployeeBenefitPlansSummaryofPensionPlanandPostretirementPlanNetPeriodicBenefitCostDetails</Role>
      <ShortName>Employee Benefit Plans Summary of Pension Plan and Postretirement Plan Net Periodic Benefit Cost (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>2466441 - Disclosure - Commitments and Contingencies Outstanding Commitments to Extend Credit and Letters of Credit (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/CommitmentsandContingenciesOutstandingCommitmentstoExtendCreditandLettersofCreditDetails</Role>
      <ShortName>Commitments and Contingencies Outstanding Commitments to Extend Credit and Letters of Credit (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>2467442 - Disclosure - Commitments and Contingencies - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/CommitmentsandContingenciesNarrativeDetails</Role>
      <ShortName>Commitments and Contingencies - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="fult-20210630.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>2469443 - Disclosure - Long-Term Borrowings (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.fult.com/role/LongTermBorrowingsDetails</Role>
      <ShortName>Long-Term Borrowings (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.fult.com/role/LongTermBorrowings</ParentRole>
      <Position>77</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="10-Q" original="fult-20210630.htm">fult-20210630.htm</File>
    <File>exhibit101.htm</File>
    <File>exhibit102.htm</File>
    <File>fult-20210630.xsd</File>
    <File>fult-20210630_cal.xml</File>
    <File>fult-20210630_def.xml</File>
    <File>fult-20210630_lab.xml</File>
    <File>fult-20210630_pre.xml</File>
    <File>fult63021-exhibit311.htm</File>
    <File>fult63021-exhibit312.htm</File>
    <File>fult63021-exhibit321.htm</File>
    <File>fult63021-exhibit322.htm</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy>http://xbrl.sec.gov/dei/2020-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://fasb.org/us-gaap/2020-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://fasb.org/srt/2020-01-31</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
