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| | | <Position> 39 </Position> |
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| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/GoodwillandOtherIntangibleAssets </ParentRole> |
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| | | <ShortName> Premises and Equipment, Net (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/PremisesandEquipmentNet </ParentRole> |
| | | <Position> 43 </Position> |
| | | </Report> |
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| | | <ShortName> Deposits (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
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| | | <Position> 44 </Position> |
| | | </Report> |
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| | | <LongName> 230483008 - Disclosure - Federal Home Loan Bank Advances (Tables) </LongName> |
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| | | <ShortName> Federal Home Loan Bank Advances (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/FederalHomeLoanBankAdvances </ParentRole> |
| | | <Position> 45 </Position> |
| | | </Report> |
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| | | <LongName> 230543009 - Disclosure - Other Borrowings (Tables) </LongName> |
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| | | <ShortName> Other Borrowings (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/OtherBorrowings </ParentRole> |
| | | <Position> 46 </Position> |
| | | </Report> |
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| | | <LongName> 230593010 - Disclosure - Junior Subordinated Debentures (Tables) </LongName> |
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| | | <Role> http://www.wintrust.com/role/JuniorSubordinatedDebenturesTables </Role> |
| | | <ShortName> Junior Subordinated Debentures (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/JuniorSubordinatedDebentures </ParentRole> |
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| | | </Report> |
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| | | <LongName> 230633011 - Disclosure - Revenue from Contracts with Customers (Tables) </LongName> |
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| | | <ShortName> Revenue from Contracts with Customers (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/RevenuefromContractswithCustomers </ParentRole> |
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| | | </Report> |
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| | | <LongName> 230693012 - Disclosure - Lease Commitments (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
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| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/LeaseCommitments </ParentRole> |
| | | <Position> 49 </Position> |
| | | </Report> |
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| | | <LongName> 230753013 - Disclosure - Income Taxes (Tables) </LongName> |
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| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/IncomeTaxes </ParentRole> |
| | | <Position> 50 </Position> |
| | | </Report> |
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| | | <LongName> 230823014 - Disclosure - Stock Compensation Plans and Other Employee Benefit Plans (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.wintrust.com/role/StockCompensationPlansandOtherEmployeeBenefitPlansTables </Role> |
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| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/StockCompensationPlansandOtherEmployeeBenefitPlans </ParentRole> |
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| | | </Report> |
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| | | <LongName> 230873015 - Disclosure - Regulatory Matters (Tables) </LongName> |
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| | | <Role> http://www.wintrust.com/role/RegulatoryMattersTables </Role> |
| | | <ShortName> Regulatory Matters (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/RegulatoryMatters </ParentRole> |
| | | <Position> 52 </Position> |
| | | </Report> |
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| | | <LongName> 230943016 - Disclosure - Derivative Financial Instruments (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.wintrust.com/role/DerivativeFinancialInstrumentsTables </Role> |
| | | <ShortName> Derivative Financial Instruments (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/DerivativeFinancialInstruments </ParentRole> |
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| | | </Report> |
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| | | <LongName> 231033017 - Disclosure - Fair Value of Assets and Liabilities (Tables) </LongName> |
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| | | <MenuCategory> Tables </MenuCategory> |
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| | | </Report> |
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| | | <LongName> 231113018 - Disclosure - Shareholders' Equity (Tables) </LongName> |
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| | | <Position> 55 </Position> |
| | | </Report> |
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| | | <LongName> 231173019 - Disclosure - Segment Information (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
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| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/SegmentInformation </ParentRole> |
| | | <Position> 56 </Position> |
| | | </Report> |
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| | | <LongName> 231213020 - Disclosure - Condensed Parent Company Financial Statements (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.wintrust.com/role/CondensedParentCompanyFinancialStatementsTables </Role> |
| | | <ShortName> Condensed Parent Company Financial Statements (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/CondensedParentCompanyFinancialStatements </ParentRole> |
| | | <Position> 57 </Position> |
| | | </Report> |
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| | | <LongName> 231263021 - Disclosure - Earnings Per Share (Tables) </LongName> |
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| | | <ShortName> Earnings Per Share (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/EarningsPerShare </ParentRole> |
| | | <Position> 58 </Position> |
| | | </Report> |
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| | | <LongName> 231293022 - Disclosure - Quarterly Financial Summary (Unaudited) (Tables) </LongName> |
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| | | <MenuCategory> Tables </MenuCategory> |
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| | | </Report> |
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| | | <LongName> 240034001 - Disclosure - Summary Of Significant Accounting Policies (Narrative) (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
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| | | <MenuCategory> Details </MenuCategory> |
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| | | </Report> |
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| | | <LongName> 240074002 - Disclosure - Investment Securities (Schedule of Investment Securities) (Details) </LongName> |
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| | | <Role> http://www.wintrust.com/role/InvestmentSecuritiesScheduleofInvestmentSecuritiesDetails </Role> |
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| | | <MenuCategory> Details </MenuCategory> |
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| | | </Report> |
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| | | <MenuCategory> Details </MenuCategory> |
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| | | </Report> |
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| | | <LongName> 240094004 - Disclosure - Investment Securities (Schedule of Investment Securities Portfolio Continuous Unrealized Loss Position) (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.wintrust.com/role/InvestmentSecuritiesScheduleofInvestmentSecuritiesPortfolioContinuousUnrealizedLossPositionDetails </Role> |
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| | | <MenuCategory> Details </MenuCategory> |
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| | | <LongName> 240104005 - Disclosure - Investment Securities (Schedule of Available-for-Sale Investment Securities Gross Gains and Gross Losses Realized) (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.wintrust.com/role/InvestmentSecuritiesScheduleofAvailableforSaleInvestmentSecuritiesGrossGainsandGrossLossesRealizedDetails </Role> |
| | | <ShortName> Investment Securities (Schedule of Available-for-Sale Investment Securities Gross Gains and Gross Losses Realized) (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
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| | | </Report> |
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| | | <LongName> 240114006 - Disclosure - Investment Securities (Contractual Maturities of Investment Securities) (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.wintrust.com/role/InvestmentSecuritiesContractualMaturitiesofInvestmentSecuritiesDetails </Role> |
| | | <ShortName> Investment Securities (Contractual Maturities of Investment Securities) (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
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| | | <LongName> 240144007 - Disclosure - Loans (Summary of Loan Portfolio) (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.wintrust.com/role/LoansSummaryofLoanPortfolioDetails </Role> |
| | | <ShortName> Loans (Summary of Loan Portfolio) (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/LoansTables </ParentRole> |
| | | <Position> 66 </Position> |
| | | </Report> |
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| | | <ReportType> Sheet </ReportType> |
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| | | <ShortName> Loans (Narrative) (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/LoansTables </ParentRole> |
| | | <Position> 67 </Position> |
| | | </Report> |
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| | | <LongName> 240164009 - Disclosure - Loans (Unpaid Principal Balance and Carrying Value of Acquired Loans) (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.wintrust.com/role/LoansUnpaidPrincipalBalanceandCarryingValueofAcquiredLoansDetails </Role> |
| | | <ShortName> Loans (Unpaid Principal Balance and Carrying Value of Acquired Loans) (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/LoansTables </ParentRole> |
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| | | </Report> |
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| | | <LongName> 240174010 - Disclosure - Loans (Activity Related to Accretable Yield of Loans Acquired with Evidence of Credit Quality Deterioration Since Origination) (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.wintrust.com/role/LoansActivityRelatedtoAccretableYieldofLoansAcquiredwithEvidenceofCreditQualityDeteriorationSinceOriginationDetails </Role> |
| | | <ShortName> Loans (Activity Related to Accretable Yield of Loans Acquired with Evidence of Credit Quality Deterioration Since Origination) (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/LoansTables </ParentRole> |
| | | <Position> 69 </Position> |
| | | </Report> |
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| | | <LongName> 240204011 - Disclosure - Allowance for Credit Losses (Schedule of Aging of the Company's Loan Portfolio) (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.wintrust.com/role/AllowanceforCreditLossesScheduleofAgingoftheCompanysLoanPortfolioDetails </Role> |
| | | <ShortName> Allowance for Credit Losses (Schedule of Aging of the Company's Loan Portfolio) (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/AllowanceforCreditLossesTables </ParentRole> |
| | | <Position> 70 </Position> |
| | | </Report> |
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| | | <LongName> 240214012 - Disclosure - Allowance for Credit Losses (Loan Portfolio by Credit Quality Indicator) (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.wintrust.com/role/AllowanceforCreditLossesLoanPortfoliobyCreditQualityIndicatorDetails </Role> |
| | | <ShortName> Allowance for Credit Losses (Loan Portfolio by Credit Quality Indicator) (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.wintrust.com/role/AllowanceforCreditLossesTables </ParentRole> |
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| | | </Report> |
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