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Income Tax Authority, Name [Axis] Income Tax Authority, Name [Domain] Common Equity Tier 1 Capital (to Risk Weighted Assets), well capitalized, minimum ratio Tier 1 Capital (to Risk Weighted Assets), well capitalized, minimum ratio Tier 1 Capital (to Risk Weighted Assets), ratio us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss The 2023 Equity Plan [Member] Represents the 2023 Equity Plan. Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table Text Block] Loans, net us-gaap_LoansReceivableFairValueDisclosure Director Fee Continuation Plan (DFCP) [Member] Represents the Director Fee Continuation Plan (DFCP). Debt Securities, Available-for-Sale, Unrealized Loss Position ecbk_DebtSecuritiesAvailableforsaleDelinquentAmount Debt Securities, Available-for-Sale, Delinquent Amount Amount investments in debt securities classified as available-for-sale that are delinquent at the end of the reporting period. ecbk_DebtSecuritiesHeldtoMaturityDelinquentAmount Debt Securities, Held-to-Maturity, Delinquent Amount Amount investments in debt securities classified as held-to-maturity that are delinquent at the end of the reporting period. Federal Home Loan Bank stock us-gaap_InvestmentInFederalHomeLoanBankStockFairValueDisclosure Derivative instruments, liabilities us-gaap_DerivativeLiabilities Mortgage-Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positionssecurities Financing Receivable, Allowance for Credit Loss [Table Text Block] us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber Balance (in shares) Balance (in shares) Balance, weighted average fair value (in dollars per share) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue Balance, weighted average fair value (in dollars per share) Financing Receivable, Past Due [Table Text Block] Granted, RSA (in shares) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod Granted, weighted average fair value (in dollars per share) Federal Home Loan Bank advances us-gaap_FederalHomeLoanBankBorrowingsFairValueDisclosure us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod Forfeited, RSA (in shares) Financing Receivable Credit Quality Indicators [Table Text Block] Vested, weighted average fair value (in dollars per share) Non-vested awards, amount us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod Vested, RSA (in shares) Collateralized Mortgage Obligations [Member] Loan Origination Commitments [Member] Commercial Loan [Member] Interest and fees on loans us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares) Commitments to Extend Credit [Member] Measurement Frequency [Axis] ASSETS us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber Balance (in shares) Balance (in shares) Commitments and Contingencies Disclosure [Text Block] Proceeds from paydowns and maturities of available-for-sale securities us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice Balance, weighted average exercise price (in dollars per share) Balance, weighted-average exercise price (in dollars per share) Statement [Line Items] us-gaap_FairValueNetAssetLiability Fair Value, Net Asset (Liability) Liability Class [Axis] Fair Value Hierarchy and NAV [Axis] Common stock, issued (in shares) Grantee Status [Domain] Common stock, outstanding (in shares) Award Type [Domain] Common stock, authorized (in shares) Grantee Status [Axis] Proceeds from long-term Federal Home Loan Bank advances Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Massachusetts Department of Revenue [Member] Related to Massachusetts Department of Revenue. Total loans, gross, percent Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Share-Based Payment Arrangement, Nonemployee [Member] Common Stock, par value $0.01; Authorized: 30,000,000 shares; Issued and outstanding: 8,773,025 shares and 8,792,719 shares at March 31, 2026 and December 31, 2025, respectively us-gaap_ProceedsFromIssuanceOfCommonStock Proceeds from Issuance of Common Stock us-gaap_MortgageLoansInProcessOfForeclosureAmount Mortgage Loans in Process of Foreclosure, Amount us-gaap_PolicyTextBlockAbstract Accounting Policies us-gaap_DisclosureTextBlockAbstract Notes to Financial Statements us-gaap_TableTextBlock Notes Tables Comprehensive Income (Loss) Note [Text Block] us-gaap_ComprehensiveIncomeNetOfTax Total comprehensive income Short-term investments us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestWriteoff Debt Securities, Available-for-Sale, Accrued Interest Writeoff Net deferred loan fees Proceeds from paydowns and maturities of held-to-maturity securities Vested, weighted average exercise price (in dollars per share) Weighted average price at which options vest. Loans held-for-sale Construction Loans [Member] Deposits us-gaap_DepositsFairValueDisclosure Tier 1 Capital (to Risk Weighted Assets), minimum for adequacy adequacy Amount of minimum Tier 1 risk-based capital required for capital adequacy as defined by regulatory framework including buffer. Total Capital (to Risk Weighted Assets), minimum for adequacy adequacy ratio Ratio of minimum Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework including the buffer. Federal Home Loan Bank Advances [Member] Tier 1 Capital (to Risk Weighted Assets), minimum for adequacy adequacy ratio Ratio of minimum Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework, including buffer. Total Capital (to Risk Weighted Assets), minimum for adequacy adequacy Amount of minimum total risk-based capital required for capital adequacy as defined by regulatory framework including the buffer. Consumer Loan [Member] us-gaap_DebtSecuritiesAvailableForSaleAndHeldToMaturityAmortizedCostAfterAllowanceForCreditLoss Debt Securities, Available-for-Sale and Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss Federal Home Loan Bank stock, at cost Standby Letters of Credit [Member] Tier 1 Capital (to Average Assets), minimum for adequacy adequacy ratio Ratio of minimum Tier 1 leverage capital to average assets required for capital adequacy as defined by regulatory framework including buffer. Common Equity Tier 1 Capital (to Risk Weighted Assets), minimum for adequacy adequacy Tier 1 Capital (to Average Assets), minimum for adequacy adequacy Amount of minimum Tier 1 leverage capital required for capital adequacy as defined by regulatory framework including minimum. Common Equity Tier 1 Capital (to Risk Weighted Assets), minimum for adequacy adequacy ratio Ratio of minimum Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework including buffer. Other comprehensive income (loss), net of tax: Statement of Stockholders' Equity [Abstract] Loss Contingency Nature [Axis] Statement of Comprehensive Income [Abstract] us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesTaxPortionAttributableToParent Available-for-sale securities, income tax expense Proceeds from sales of loans Statement of Cash Flows [Abstract] Financing Receivable Portfolio Segment [Axis] us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent Total other comprehensive income (loss), net of tax Other comprehensive loss, net of tax Shareholders' Equity: Equity Components [Axis] Net change in fair value of securities available-for-sale us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent Available-for-sale securities, net-of-tax amount Real Estate Loan [Member] Financing Receivable Portfolio Segment [Domain] Home Equity Loan [Member] Equity Component [Domain] Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 3 [Member] AOCI Attributable to Parent [Member] Fair Value, Inputs, Level 1 [Member] Additional Paid-in Capital [Member] Retained Earnings [Member] Corporate Debt Securities [Member] Loss Contingency, Nature [Domain] Residential Real Estate [Member] Premises and equipment, net Financial Asset, Aging [Axis] Financing Receivable, Nonaccrual [Table Text Block] Deferred tax asset, net Financial Asset, Aging [Domain] Sale of Stock [Axis] Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block] Provision (benefit) for credit losses Total provision (benefit) for credit losses Amortized Cost, Held-to-maturity Subsidiary or Equity Method Investee, Sale of Stock [Table] ecbk_ContributionOfCash Contribution of Cash Represents cash contributed. Financial Asset, 30 to 59 Days Past Due [Member] ecbk_UnallocatedESOPShares Unallocated common shares held by the Employee Stock Ownership Plan Fair value of unearned shares for all classes of common stock and nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by an employee stock ownership plan (ESOP). Includes the sale of shares or the issuance treasury shares to an ESOP. Stock-based compensation Amortized Cost, Available-for-sale ecbk_StockIssuedDuringPeriodSharesContributed Stock Issued During Period, Shares Contributed (in shares) Represents shares contributed. Allowance for Credit Losses, Held-to-Maturity Held-to-maturity securities ecbk_DebtSecuritiesHeldtomaturityExcludingAccruedInterestFairValue Fair value of investment in debt security measured at amortized cost (held-to-maturity). Allowance for credit losses for loans Allowance for credit losses Balance Balance Financial Asset, 60 to 89 Days Past Due [Member] Financial Asset, Equal to or Greater than 90 Days Past Due [Member] Allowance for Credit Losses, Available-for-sale Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest Share-Based Payment Arrangement, Option, Activity [Table Text Block] Deferred Compensation, Share-Based Payments [Member] Share-Based Payment Arrangement, Cost by Plan [Table Text Block] us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear Year five us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear Prior us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear Year three us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear Year four Fair Value Disclosures [Text Block] us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear Year one Share-Based Payment Arrangement, Nonvested Award, Cost [Table Text Block] us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear Year two Share-Based Payment Arrangement, Option [Member] Supplemental disclosures: us-gaap_FinancingReceivableExcludingAccruedInterestRevolving Revolving Schedule of Interest Rate Derivatives [Table Text Block] us-gaap_FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoan Revolving, converted to term loan us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments Accretion of premiums and discounts on securities, net Loans held-for-sale us-gaap_LoansHeldForSaleFairValueDisclosure Collateral Held [Domain] Weighted-average maturity in years (Year) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod Forfeited or expired (in shares) Collateral Held [Axis] us-gaap_PaymentsToAcquireEquityMethodInvestments Investment in low-income housing tax credit fund Federal Reserve Bank Advances [Member] Other Commitments [Table] Tier 1 Capital (to Risk Weighted Assets), well capitalized, minimum Tier 1 Capital (to Risk Weighted Assets) Accumulated other comprehensive loss Accumulated other comprehensive loss Tier 1 Capital (to Average Assets), well capitalized, minimum Forfeited or expired, weighted average exercise price (in dollars per share) Tier 1 Capital (to Average Assets) us-gaap_PaymentsToAcquireLoansHeldForInvestment Loan originations and principal collections, net us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest Income before income tax expense Data processing Additional paid-in capital us-gaap_MaximumLengthOfTimeHedgedInCashFlowHedge1 Cash Flow Hedge, Hedging Exposure, Maximum Period (Year) Non-vested awards, period (Year) us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1 Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] ESOP shares committed to be released Total Capital (to Risk Weighted Assets) us-gaap_PaymentsToAcquirePropertyPlantAndEquipment Capital expenditures Collateralized Mortgage-Backed Securities [Member] Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table] us-gaap_StockRepurchasedAndRetiredDuringPeriodValue Shares repurchased under share repurchase plan us-gaap_NoninterestExpense Total noninterest expense Noninterest expense: Commercial Loans [Member] Financial Asset, Not Past Due [Member] Total Capital (to Risk Weighted Assets), well capitalized, minimum us-gaap_StockIssuedDuringPeriodSharesNewIssues Stock Issued During Period, Shares, New Issues (in shares) us-gaap_OffBalanceSheetCreditLossLiability Off-Balance-Sheet, Credit Loss, Liability us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised Exercised (in shares) us-gaap_StockRepurchasedAndRetiredDuringPeriodShares Shares repurchased under share repurchase plan (in shares) IPO [Member] Cash flows from operating activities: Cash flows from investing activities: us-gaap_NetCashProvidedByUsedInOperatingActivities Net cash provided by (used in) operating activities Cash flows from financing activities: us-gaap_NetCashProvidedByUsedInInvestingActivities Net cash used in investing activities us-gaap_SharesIssuedPricePerShare Shares Issued, Price Per Share (in dollars per share) us-gaap_NetCashProvidedByUsedInFinancingActivities Net cash provided by financing activities Federal Home Loan Bank advances us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt Purchases of available-for-sale securities us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt Proceeds from Sale of Debt Securities, Available-for-Sale us-gaap_LiabilitiesFairValueDisclosure Total liabilities measured at fair value on a recurring basis us-gaap_AssetsFairValueDisclosure Total assets measured at fair value on a recurring basis Shares (in shares) Accounting Policies [Abstract] Net unrealized holding gain on securities available-for-sale, net of tax us-gaap_AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax Unrecognized gain, net of tax Loans, net of allowance for credit losses of $10,412 at March 31, 2026, and $10,255 at December 31, 2025. Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss Total loans, net us-gaap_StockRepurchasedDuringPeriodValue Shares repurchased under share repurchase plan us-gaap_StockRepurchasedDuringPeriodShares Shares repurchased under share repurchase plan (in shares) Income Statement [Abstract] us-gaap_OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal Benefit for losses on off-balance sheet credit exposures Net (decrease) increase in demand deposits, interest-bearing checking, savings and money market accounts Available-for-sale securities Investments in available-for-sale securities, at fair value Investments in held-to-maturity securities, at cost (fair values of $48,044 as of March 31, 2026, and $52,326 at December 31, 2025) Deferred income tax expense us-gaap_AmortizationOfDeferredLoanOriginationFeesNet Change in deferred loan costs/fees Net increase in time deposits Net income allocated to common stock Net income Net income Financial Asset, Past Due [Member] us-gaap_DerivativeLiabilityCollateralRightToReclaimCashOffset Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Offset Supplemental Executive Retirement Plan (SERP) [Member] Represents the Supplemental Executive Retirement Plan (SERP). us-gaap_InterestIncomeExpenseNet Net interest and dividend income Unused lines of Credit [Member] Accumulated Other Comprehensive Income (Loss) [Table] us-gaap_InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net Restricted Stock [Member] Interest Income recognized Financing Receivable, Nonaccrual, Interest Income Reinsurance Recoverables, Including Reinsurance Premium Paid Occupancy and equipment Other expense Federal Deposit Insurance Corporation deposit insurance us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue Increase in bank-owned life insurance Income from bank-owned life insurance us-gaap_NoninterestIncome Total noninterest income Noninterest income: Measurement Basis [Axis] Fair Value Hierarchy and NAV [Domain] Other income Net gain on sales of loans Gain on sales of loans, net Measurement Frequency [Domain] Statement of Financial Position [Abstract] us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestCreditLossExpenseReversal Debt Securities, Held-to-Maturity, Excluding Accrued Interest, Credit Loss Expense (Reversal) (Benefit) provision Provision for losses on loans Advertising and promotions Recoveries Other assets us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff Charge-offs Current-period gross charge-offs Director compensation us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterestAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal Debt Securities, Available-for-Sale, Excluding Accrued Interest, Allowance for Credit Loss, Not to Sell before Recovery, Credit Loss, Previously Recorded, Expense (Reversal) Fair Value, Nonrecurring [Member] Professional fees Fair Value, Recurring [Member] Common Equity Tier 1 Capital (to Risk Weighted Assets) us-gaap_PaymentsForRepurchaseOfCommonStock Payments for shares repurchased under share repurchase plan us-gaap_IncreaseDecreaseInOtherOperatingAssets Decrease (increase) in other assets Document Type After 5 years through 10 years, Held-to-maturity, amortized cost After 10 years, Held-to-maturity, amortized cost Document Information [Line Items] Document Quarterly Report Within 1 year, Held-to-maturity, amortized cost After 1 year through 5 years, Held-to-maturity, amortized cost Document Information [Table] Common Equity Tier 1 Capital (to Risk Weighted Assets), well capitalized, minimum us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares) Antidilutive Securities [Axis] Entity Interactive Data Current Other State Tax Authorities [Member] Relating to other state tax authorities. Bank-owned life insurance Document Transition Report Weighted average shares outstanding, diluted (in shares) Weighted-average common shares outstanding used to calculate diluted earnings per common share (in shares) us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDate Held-to-maturity, amortized Cost Share data: us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate Available-for-sale, Fair Value Add: Dilutive effect of share-based compensation (in shares) Weighted-average common shares outstanding used to calculate basic earnings per common share (in shares) Weighted average shares outstanding, basic (in shares) us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue Held-to-maturity, Fair Value Derivative Instrument [Axis] Basic (in dollars per share) Earnings per share, basic (in dollars per share) Total loans,90 days past due and accruing Earnings Per Share, Basic, by Common Class, Including Two-Class Method [Table] Total nonaccrual loans, without allowance for credit loss Total loans, nonaccrual State us-gaap_IncomeTaxPaidStateAndLocalAfterRefundReceived Interest-bearing Debt Securities, Available-for-Sale [Table Text Block] us-gaap_Deposits Total deposits Federal us-gaap_IncomeTaxPaidFederalAfterRefundReceived Noninterest-bearing Lease Deposit Liability Document Fiscal Period Focus Pledging Purpose [Axis] Document Fiscal Year Focus Pledging Purpose [Domain] Amendment Flag Financing Receivables [Text Block] Common Stock [Member] Financing Receivable, Past Due [Table] Decrease in other liabilities us-gaap_PaymentsToAcquireFederalHomeLoanBankStock Purchase of Federal Home Loan Bank Stock Redemption of Federal Home Loan Bank Stock Document Period End Date Interest and dividend income: Granted (in shares) Legal Entity [Axis] us-gaap_InterestAndDividendIncomeOperating Total interest and dividend income Financing Receivable, Allowance for Credit Loss [Table] Award Date [Axis] Entity File Number Weighted-average pay rate us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax Available-for-sale securities, total Entity Tax Identification Number Fair value asset us-gaap_DerivativeFairValueOfDerivativeAsset us-gaap_DerivativeFairValueOfDerivativeLiability Fair value liability us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Entity [Domain] Entity Central Index Key Entity Registrant Name Doubtful [Member] Entity Current Reporting Status Special Mention [Member] Substandard [Member] Entity Incorporation, State or Country Code Pass [Member] Current Fiscal Year End Date Entity Ex Transition Period Entity Filer Category Entity Shell Company Derivative Liability, Statement of Financial Position Entity Emerging Growth Company Award Date [Domain] Notional amount Derivative Asset, Statement of Financial Position Entity Small Business Hedging Designation [Domain] Derivative instruments us-gaap_DerivativeAssets Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Weighted-average receive rate Vested, nonvested (in shares) Interest-bearing time deposits Derivative Instruments and Hedging Activities Disclosure [Text Block] us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares Balance, nonvested (in shares) Balance, nonvested (in shares) Interest on deposits Entity Address, State or Province Entity Address, City or Town Forfeited or expired, nonvested, weighted average exercise price (in dollars per share) Retained earnings us-gaap_InterestExpenseOperating Total interest expense Entity Address, Address Line One us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedWeightedAverageGrantDateFairValue Balance, nonvested, weighted average exercise price (in dollars per share) Balance, nonvested, weighted average exercise price (in dollars per share) Vested, nonvested, weighted average exercise price (in dollars per share) City Area Code Interest expense: Local Phone Number Entity Address, Postal Zip Code Derivative [Table] Title of 12(b) Security Security Exchange Name After 5 years through 10 years, Available-for-sale, fair value Trading Symbol After 10 years, Available-for-sale, fair value Within 1 year, Available-for-sale, fair value After 1 year through 5 years, Available-for-sale, fair value Class of Stock [Axis] Interest on Federal Home Loan Bank advances Class of Financing Receivable [Axis] Class of Financing Receivable [Domain] Entity Common Stock, Shares Outstanding Earnings Per Share [Text Block] Hedging Designation [Axis] Financing Receivable, Credit Quality Indicator [Table] Total loans, gross Total loans, gross Change in fair value of available-for-sale securities Internal Credit Assessment [Axis] Debt Securities, Held-to-Maturity [Table] Debt Securities, Held-to-Maturity [Table Text Block] Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table] Investments in held-to-maturity securities, fair value us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss Net interest and dividend income after provision (benefit) for credit losses Deposits, Excluding Certificates of Deposit [Member] Represents deposits, excluding certificates of deposit. Derivative Instruments, Gain (Loss) [Table Text Block] Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block] Investments Classified by Contractual Maturity Date [Table Text Block] Interest on interest-bearing time deposits Internal Credit Assessment [Domain] After 5 years through 10 years, Held-to-maturity, fair value Common stock, par value (in dollars per share) After 10 years, Held-to-maturity, fair value Within 1 year, Held-to-maturity, fair value After 1 year through 5 years, Held-to-maturity, fair value Other liabilities Derivative Contract [Domain] Fair Value Measurements, Recurring and Nonrecurring [Table Text Block] Federal Reserve Bank [Member] Relating to Federal Reserve Bank. Sale of Stock [Domain] Regulatory Capital Requirements under Banking Regulations [Text Block] Cash and due from banks us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax Reclassification adjustment for realized gains in net income us-gaap_CashCashEquivalentsAndFederalFundsSold Total cash and cash equivalents us-gaap_Assets Total assets Designated as Hedging Instrument [Member] Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Financing Receivable, Nonaccrual [Table] Proceeds from maturities of interest-bearing time deposits The cash inflow in Interest-bearing Deposits by banks in other financial institutions for relatively short periods of time including, for example, certificates of deposits. ecbk_PaymentsForInInterestbearingDepositsInBanks Purchase of interest-bearing time deposits The cash outflow in Interest-bearing Deposits by banks in other financial institutions for relatively short periods of time including, for example, certificates of deposits. us-gaap_FinancingReceivableExcludingAccruedInterestModifiedPeriod Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount Interest and dividends on securities Diluted (in dollars per share) Earnings per share, diluted (in dollars per share) Debt Securities, Trading, and Equity Securities, FV-NI [Table] Depreciation and amortization expense Accounts and Financing Receivables [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Fair Value by Liability Class [Domain] Computer software and licensing The amount of expense incurred in the period for computer software and licensing. Accrued interest receivable Interest paid Interest Rate Swap [Member] us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff Current-period gross charge-offs, prior us-gaap_FinancingReceivableExcludingAccruedInterestRevolvingWriteoff Current-period gross charge-offs, revolving us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff Current-period gross charge-offs, year four us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff Current-period gross charge-offs, year five us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff Current-period gross charge-offs, year two us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff Current-period gross charge-offs, year three us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYearWriteoff Current-period gross charge-offs, year one Corporate Bond Securities [Member] us-gaap_FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoanWriteoff Current-period gross charge-offs, revolving, converted to term loan us-gaap_DebtSecuritiesHeldToMaturityAccruedInterestAfterAllowanceForCreditLoss Debt Securities, Held-to-Maturity, Accrued Interest, after Allowance for Credit Loss us-gaap_StockholdersEquity Total shareholders' equity Balance Balance Forfeited, weighted average fair value (in dollars per share) us-gaap_FinancingReceivableAccruedInterestAfterAllowanceForCreditLoss Financing Receivable, Accrued Interest, after Allowance for Credit Loss Granted in 2025 [Member] Represents granted in 2025. us-gaap_DebtSecuritiesHeldToMaturityAccruedInterestWriteoff Debt Securities, Held-to-Maturity, Accrued Interest, Writeoff us-gaap_PaymentsForOriginationOfMortgageLoansHeldForSale Loans originated for sale, net Consolidation, Less-than-Wholly-Owned Subsidiary, Parent Ownership Interest, Effect of Change [Table] us-gaap_RepaymentsOfFederalHomeLoanBankBorrowings Repayments of long-term Federal Home Loan Bank advances us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss ecd_Rule10b51ArrTrmntdFlag Rule 10b5-1 Arrangement Terminated [Flag] Customer service fees ecd_Rule10b51ArrAdoptedFlag Rule 10b5-1 Arrangement Adopted [Flag] Commitments and contingencies (see Note 7)