Document And Entity Information
Schedule of Evaluation of Impairment on Financing Receivables [Table Text Block]
Tabular disclosure of evaluation for impairment of financing receivables.
Statistical Measurement [Axis]
Note To Financial Statement Details Textual
Significant Accounting Policies
Note 2 - Business Combination
Schedule of Allowance for Credit Losses on Unfunded Commitments [Table Text Block]
Tabular disclosure of allowance for credit losses on unfunded commitments.
Income Tax Expense (Benefit)
Income tax expense
Pension Plan [Member]
ecd_NonRule10b51ArrTrmntdFlag
Non-Rule 10b5-1 Arrangement Terminated [Flag]
Note 3 - Earnings Per Common Share
ecd_NonRule10b51ArrAdoptedFlag
Non-Rule 10b5-1 Arrangement Adopted [Flag]
Note 4 - Investment Securities
Trading Arrangements, by Individual [Table]
Note 5 - Derivatives
Financing Receivable, Collateral Dependent [Table Text Block]
Tabular disclosure of collateral dependent financing receivables.
Retirement Benefits [Text Block]
Material Terms of Trading Arrangement [Text Block]
Note 6 - Loans and the Allowance for Credit Losses
Other Collateral Pledged [Member]
Represents other collateral pledged.
Note 7 - Fair Value Measurements and Fair Value of Financial Instruments
Collateral dependent loans, fair value
Collateral dependent loans
Fair value portion of impaired financing receivable.
Note 8 - Comprehensive Income
Financial Instrument [Axis]
Investment in Debt and Equity Securities and Other Trading Assets [Text Block]
us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation
Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation (in shares)
Note 9 - Stock Based Compensation
Note 10 - Components of Net Periodic Pension Cost
Collateral dependent loans, rate
cnob_ImpairedLoansMeasurementInput
Value of input used to measure impaired loan.
Minimum [Member]
Note 11 - Deposits
us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Gross unrealized losses
Schedule of Provision for (Reversal of) Credit Losses [Table Text Block]
Tabular disclosure of the provision for (reversal of) credit losses.
Note 12 - FHLB Borrowings
Gross unrealized gains
Statistical Measurement [Domain]
Note 13 - Subordinated Debentures
us-gaap_SharePrice
Share Price (in dollars per share)
Maximum [Member]
Note 14 - Segment Reporting
Note 2 - Business Combination - Schedule of Purchase Price Consideration (Details)
Note 2 - Business Combination - Schedule of PCD Loans Acquired (Details)
Note 2 - Business Combination - Pro Forma Information (Details)
Price per share of ConnectOne common stock on June 1, 2025 (in dollars per share)
Retirement Plan Name [Domain]
Federal Home Loan Bank, Advances [Text Block]
Note 3 - Earnings Per Common Share - Computation of Earnings Per Common Share (Details)
Retirement Plan Type [Domain]
Appraisals of Collateral Value [Member]
Represents appraisals of collateral value.
Note 4 - Investment Securities - Portfolio of Securities Available-for-sale (Details)
Retirement Plan Name [Axis]
Note 4 - Investment Securities - Scheduled Maturities (Details)
Note 4 - Investment Securities - Securities in an Unrealized Loss Position (Details)
Retirement Plan Type [Axis]
Note 5 - Derivatives - Net Losses Recorded in Other Comprehensive Income (Details)
Note 5 - Derivatives - Cash Flow Hedges Included in Consolidated Statements of Condition (Details)
Accrued interest receivable
cnob_AccruedInterestReceivableFairValueDsiclosure
Fair value portion of accrued interest receivables.
Note 5 - Derivatives - Schedule of Non Hedging Derivatives (Details)
Note 6 - Loans and the Allowance for Credit Losses - Composition of Loan Portfolio (Details)
Note 6 - Loans and the Allowance for Credit Losses - Composition of Loans Held-for-sale (Details)
Noninterest-bearing deposits
cnob_NoninterestBearingDepositsFairValueDisclosure
Fair value portion of noninterest-bearing deposit liabilities held by the entity.
Note 6 - Loans and the Allowance for Credit Losses - Loans Receivable on Nonaccrual Status (Details)
Note 6 - Loans and the Allowance for Credit Losses - Loans Purchased with Credit Deterioration (Details)
Note 6 - Loans and the Allowance for Credit Losses - Loans by Origination and Risk Designation (Details)
Note 6 - Loans and the Allowance for Credit Losses - Collateral Dependent Loans (Details)
The 2017 Equity Compensation Plan [Member]
Represents the 2017 Equity Compensation Plan.
us-gaap_DefinedBenefitPlanBenefitObligationPeriodIncreaseDecrease
Defined Benefit Plan, Benefit Obligation, Period Increase (Decrease)
Note 6 - Loans and the Allowance for Credit Losses - Analysis of Aging of Loans (Details)
Restricted Stock, Options and Restricted Stock Units [Member]
Represents restricted stock, options and restricted stock units.
Note 6 - Loans and the Allowance for Credit Losses - Impairment Evaluation on Loans and Allowance for Credit Losses (Details)
Commercial Mortgage-Backed Securities [Member]
us-gaap_DebtSecuritiesAvailableForSaleRestricted
Debt Securities, Available-for-Sale, Restricted
Vesting Each Year [Member]
Represents vesting each year.
Note 6 - Loans and the Allowance for Credit Losses - Activity in the ACL for Loans (Details)
cnob_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedTovested
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Expected toVested (in shares)
The number of equity-based payment instruments, excluding stock (or unit) options, that are expected to vest.
Note 6 - Loans and the Allowance for Credit Losses - Amortized Cost of of the Modified Loans (Details)
Note 6 - Loans and the Allowance for Credit Losses - Aging of Modified Loans (Details)
Interest-bearing deposits
cnob_InterestBearingDepositsFairValueDisclosure
Fair value portion of interest bearing deposit liabilities held by the entity.
Note 6 - Loans and the Allowance for Credit Losses - Rollforward of Allowance for Credit Losses for Unfunded Commitments (Details)
Note 6 - Loans and the Allowance for Credit Losses - Summary of (Reversal of) Provision for Credit Losses (Details)
Note 7 - Fair Value Measurements and Fair Value of Financial Instruments - Assets and Liabilities Measured on a Recurring Basis (Details)
Note 7 - Fair Value Measurements and Fair Value of Financial Instruments - Assets Measured on a Nonrecurring Basis (Details)
Note 7 - Fair Value Measurements and Fair Value of Financial Instruments - Assets Measured on Recurring Basis Using Significant Unobservable Inputs (Details)
cnob_FederalHomeLoanBankAdvanceFairValueDiscount
Fair value discount, amount
Amount of discount on advances from the Federal Home Loan Bank (FHLB).
Center Bancorp Statutory Trust II [Member]
Represents Center Bancorp Statutory Trust II.
Note 7 - Fair Value Measurements and Fair Value of Financial Instruments - Quantitative Information About Significant Unobservable Inputs (Details)
us-gaap_DefinedBenefitPlanCurtailments
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment
Note 7 - Fair Value Measurements and Fair Value of Financial Instruments - Significant Unobservable Inputs for Assets Measured on Nonrecurring Basis (Details)
Unearned, units (maximum) (in shares)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Expected to Vest, Performance Obligations Exceeded (in shares)
The number of equity-based payment instruments, excluding stock (or unit) options, that are expected to vest if performance targets are exceeded.
Note 7 - Fair Value Measurements and Fair Value of Financial Instruments - Carrying Value and Fair Value of Financial Instruments (Details)
Note 8 - Comprehensive Income - Reclassification out of Accumulated Other Comprehensive (Details)
Note 8 - Comprehensive Income - Accumulated Other Comprehensive (Loss) Income (Details)
Note 9 - Stock Based Compensation - Activity in Restricted Shares (Details)
Note 9 - Stock Based Compensation - Summary of Unearned Performance Unit Awards (Details)
Note 9 - Stock Based Compensation - Summary of Unearned Restricted Stock Units (Details)
Salaries and employee benefits
Salaries and employee benefits
Note 10 - Components of Net Periodic Pension Cost - Net Periodic Pension Cost (Details)
us-gaap_DividendsCommonStockCash
Cash dividends declared on common stock
Note 11 - Deposits - Schedule of Time Deposits (Details)
Note 12 - FHLB Borrowings - FHLB Borrowings and Weighted Average Interest Rates (Details)
Performance Shares [Member]
Note 13 - Subordinated Debentures - Summary of Mandatory Redeemable Trust Preferred Securities (Details)
Note 14 - Segment Reporting - Schedule of Segment Reporting (Details)
us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate
Notes To Financial Statements
Interest cost
Notes To Financial Statements [Abstract]
cnob_AccretionOnDeposits
Amortization on deposits
mount of accretion on deposits.
us-gaap_DefinedBenefitPlanFundedStatusOfPlan
Defined Benefit Plan, Funded (Unfunded) Status of Plan
us-gaap_DefinedBenefitPlanFundedPercentage
Defined Benefit Plan, Funded Percentage
Financial Instruments [Domain]
us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
Expected return on plan assets
us-gaap_DividendsPreferredStockCash
Cash dividends declared on preferred stock
Cash dividends declared on common stock, per share (in dollars per share)
Asset Pledged as Collateral [Member]
Weighted Average [Member]
us-gaap_IncreaseDecreaseInAccruedInterestReceivableNet
Increase in accrued interest receivable
us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
Total periodic pension income
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration [Member]
Segment Reporting [Text Block]
Temporarily impaired securities, fair value, 12 months or longer
Temporarily impaired securities, fair value, less than 12 months
Award Type [Axis]
Segment Reporting [Table Text Block]
Adjustments to reconcile net income to net cash provided by operating activities:
Preferred Stock, no par value: 1,000 per share liquidation preference; Authorized 5,000,000 shares; issued 115,000 shares as of March 31, 2026 and as of December 31, 2025; outstanding 115,000 shares as of March 31, 2026 and as of December 31, 2025
Plan Name [Axis]
us-gaap_Liabilities
Total liabilities
Plan Name [Domain]
Defined Benefit Plan [Table]
us-gaap_AllocatedShareBasedCompensationExpense
Share-Based Payment Arrangement, Expense
us-gaap_LiabilitiesAndStockholdersEquity
Total liabilities and stockholders’ equity
Consolidation Items [Axis]
us-gaap_PaymentsToAcquireTradingSecuritiesHeldforinvestment
Purchase of equity securities
Pledged Status [Domain]
Proceeds from equity securities sold
Segment Reporting [Table]
Pledged Status [Axis]
Stock-based compensation expense
Postemployment Benefit Plans, Policy [Policy Text Block]
Consolidation Items [Domain]
us-gaap_ParticipatingSecuritiesDistributedAndUndistributedEarningsLossDiluted
Earnings allocated to participating securities
Net unrealized gains (losses) on cash flow hedges
Share-Based Payment Arrangement [Text Block]
Preferred stock, shares issued (in shares)
Preferred stock, shares outstanding (in shares)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Preferred stock, shares authorized (in shares)
Portion at Fair Value Measurement [Member]
Reported Value Measurement [Member]
us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect
Net change in cash and cash equivalents
Cash and due from banks
us-gaap_CashAndCashEquivalentsFairValueDisclosure
Estimate of Fair Value Measurement [Member]
New Accounting Pronouncements, Policy [Policy Text Block]
us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations
Cash and cash equivalents at beginning of period
Cash and cash equivalents at end of period
US Government Agencies Debt Securities [Member]
Statement [Table]
Reclassification, Comparability Adjustment [Policy Text Block]
us-gaap_TimeDeposits
Time Deposits
Time deposits (after net discount)
us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss
Temporarily impaired securities, unrealized losses
Net loans
us-gaap_LoansReceivableFairValueDisclosure
Coupon rate
Debt Instrument, Basis Spread on Variable Rate
Temporarily impaired securities, fair value
Business Combination, Consideration Transferred, Equity Interest, Type [Axis]
Equity securities
Accrued interest payable
us-gaap_AccruedLiabilitiesFairValueDisclosure
Fair value liabilities
cnob_PolicyTable
Financing Receivable, Allowance for Credit Loss [Table Text Block]
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
Nonvested, shares (in shares)
Nonvested, shares (in shares)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
Nonvested, weighted average grant date fair value (in dollars per share)
Nonvested, weighted average grant date fair value (in dollars per share)
Financing Receivable, Past Due [Table Text Block]
Granted, shares (in shares)
Awarded, units (in shares)
Granted, weighted average grant date fair value (in dollars per share)
Awarded, weighted average grant date fair value (in dollars per share)
Long-Term Debt, Type [Axis]
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod
Forfeited/cancelled/expired, shares (in shares)
Forfeited/cancelled/expired, units (in shares)
Net gains on equity securities
Financing Receivable, Modified [Table Text Block]
Consolidated Entities [Axis]
Consolidated Entities [Domain]
Vested, weighted average grant date fair value (in dollars per share)
Vested shares, weighted average grant date fair value (in dollars per share)
us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount
us-gaap_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledged1
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged
us-gaap_EquitySecuritiesFvNiUnrealizedGainLoss
Gains on equity securities, net
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares)
Vested, shares (in shares)
Vested shares, units (in shares)
Financing Receivable Origination And Risk Designation [Table Text Block]
Financing receivable origination and risk designation.
Loans held-for-sale
Loans held-for-sale
Financing Receivable, Held-for-Sale
Residential Mortgage-Backed Securities [Member]
Asset Class [Axis]
Interest and fees on loans
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)
us-gaap_ProceedsFromIssuanceOfDebt
Proceeds from Issuance of Debt
cnob_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPensionPlanAssets
Pension plan assets
The amount of pension plan assets recognized as of the acquisition date.
ConnectOne Share Entitlement [Member]
Relating to ConnectOne share entitlement.
Bank-owned Life Insurance [Member]
Relating to bank-owned life insurance.
us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLend
Financing Receivable, Modified, Commitment to Lend
Investment in Restricted Stock [Member]
Relating to investment in restricted stock.
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number (in shares)
Measurement Frequency [Axis]
ASSETS
Statement [Line Items]
FLIC Common Stock [Member]
Relating to FLIC common stock.
Fair Value Hierarchy and NAV [Axis]
cnob_BusinessAcquisitionEquityInterestIssuedOrIssuableCashPaidForFractionalShares
Fractional shares subject to cash in lieu
Represents the amount of cash paid to prevent fractional shares being issued as part of a business acquisition.
Common Stock, Shares, Issued (in shares)
Award Type [Domain]
Schedule of Loans Purchase With Credit Deterioration [Table Text Block]
The tabular disclosure of loans purchased with credit deterioration.
Common Stock, Shares, Outstanding (in shares)
The 2025 Notes [Member]
Relating to the 2025 notes.
Common Stock, Shares Authorized (in shares)
Proceeds from FHLB borrowings
cnob_BusinessCombinationAcquiredReceivablesDiscount
Non-PCD Loans, discount
For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the discount amounts, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.
Schedule of Receivables Acquired [Table Text Block]
Tabular disclosure of receivables acquired during the period.
cnob_BusinessAcquisitionProFormaNetInterestIncome
Net interest income
The pro forma net interest income for a period as if the business combination or combinations had been completed at the beginning of the period.
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]
Common stock, no par value: Authorized 100,000,000 shares; issued 54,264,042 shares as of March 31, 2026 and 54,157,402 shares as of December 31, 2025; outstanding 50,288,494 shares as of March 31, 2026 and 50,271,854 as of December 31, 2025
FLIC common shares settled for stock (in shares)
Represents the number of shares settled as part of a business acquisition.
us-gaap_PolicyTextBlockAbstract
Accounting Policies
us-gaap_DisclosureTextBlockAbstract
Notes to Financial Statements
us-gaap_TableTextBlock
Notes Tables
Comprehensive Income (Loss) Note [Text Block]
Proceeds from bank owned life insurance
us-gaap_ComprehensiveIncomeNetOfTax
Total comprehensive income
us-gaap_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresAmountOfAvailableUnusedFunds
Federal Home Loan Bank, Advances, General Debt Obligations, Amount of Available, Unused Funds
1 year through less than 2 years, rate
After 5 years, rate
Maturities, calls and principal repayments
Operating lease liabilities
Less than 1 year, rate
2 years through less than 3 years
After 5 years, amount
Federal Home Loan Bank, Advance, Branch of FHLBank [Table Text Block]
us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
Balance
Balance
us-gaap_FederalHomeLoanBankAdvancesBranchOfFHLBBankAmountOfAdvancesByBranch
FHLB borrowings – gross, amount
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]
Less than 1 year, amount
Federal Home Loan Bank Advances [Member]
2 years through less than 3 years, amount
Loans Receivable [Member]
1 year through less than 2 years, amount
Subordinated debentures
us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations
FHLB borrowings – gross, rate
Payment Deferral [Member]
Other comprehensive (loss) income, net of tax:
Statement of Stockholders' Equity [Abstract]
cnob_ImpairedFinancingReceivableRelatedAllowance1
Impaired Financing Receivable, Related Allowance 1
Amount of allowance for credit losses related to recorded investment.
Intangible Asset, Finite-Lived, Class [Axis]
Extended Maturity [Member]
cnob_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment1
Impaired Financing Receivable, with Related Allowance, Recorded Investment 1
Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.
Loan Restructuring Modification [Axis]
Statement of Comprehensive Income [Abstract]
Loan Restructuring Modification [Domain]
Intangible Asset, Finite-Lived, Class [Domain]
Equity securities
us-gaap_EquitySecuritiesFvNiCurrentAndNoncurrent
Proceeds from sale of loans held-for-sale
us-gaap_ProceedsFromSaleOfLoansHeldForSale
Statement of Cash Flows [Abstract]
Contractual Interest Rate Reduction [Member]
Financing Receivable Portfolio Segment [Axis]
Other comprehensive income (loss), net of tax
Total other comprehensive (loss) income, net of tax
Long-Term Debt, Type [Domain]
STOCKHOLDERS’ EQUITY
Equity Components [Axis]
Core Deposits [Member]
Unfunded Loan Commitment [Member]
Net change in operating leases
Financing Receivable Portfolio Segment [Domain]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis, Valuation Techniques [Table Text Block]
Equity Component [Domain]
Fair Value Measurements, Nonrecurring [Table Text Block]
Fair Value, Inputs, Level 2 [Member]
Fair Value, Inputs, Level 3 [Member]
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member]
AOCI Attributable to Parent [Member]
Fair Value, Inputs, Level 1 [Member]
Additional Paid-in Capital [Member]
Retained Earnings [Member]
Corporate Debt Securities [Member]
Subordinated Borrowings Disclosure [Text Block]
Real Estate [Member]
Subordinated Debt [Member]
Bank premises and equipment, net
Subordinated debentures, net
Financial Asset, Aging [Axis]
cnob_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentDeferredTaxAsset
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Deferred Tax Asset
This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to deferred tax assets acquired in connection with a business combination for which the initial accounting was incomplete.
Financing Receivable, Nonaccrual [Table Text Block]
Loans receivable
Total loans receivable
cnob_EffectiveIncomeTaxRateReconciliationBlendedTaxRatePercent
Effective Income Tax Rate Reconciliation, Blended Tax Rate, Percent
Percentage of income tax expense (benefit) pertaining to blended tax rate.
Financial Asset, Aging [Domain]
Exchange Ratio
Business Acquisition, Equity Interest Issued or Issuable, Share Exchange Ratio
Represents the ratio of shares exchanged as part of a business acquisition.
Total Acquired Loans, fair value
Fair value of receivable purchased, acquired in business combination.
cnob_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeposits
Deposits
Amount of deposits acquired at acquisition date.
Total Acquired Loans, unpaid principal balance
Amount of gross contractual receivable purchased, acquired in business combination.
cnob_BusinessCombinationAcquiredReceivablePcdAndNonpcdContractualCashFlowEstimatedUncollectible
Total Acquired Loans, allowance for credit losses
Amount of estimated contractual cash flow not expected to be collected for receivable purchased, acquired in business combination.
First of Long Island Corporation [Member]
Relating to First of Long Island Corporation.
cnob_BusinessCombinationAcquiredReceivablePcdAndNonpcdDiscount
Total Acquired Loans, discount
Discount of receivable purchased, acquired in business combination.
Provision for credit losses
us-gaap_ProvisionForLoanLeaseAndOtherLosses
Financial Asset, 30 to 59 Days Past Due [Member]
Schedule of Net Benefit Costs [Table Text Block]
us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
Stock-based compensation expense
Amortized cost
Total investment securities available-for-sale, amortized cost
cnob_BusinessCombinationProFormaInformationProFormaIncomeLossAfterTaxAvailableToCommonStockholders
Net income available to common stockholders
Amount, after tax, of pro forma income (loss) available to common stockholders of combined entity as if acquisition date of business combination occurred as of beginning of period.
cnob_BusinessCombinationProFormaInformationProFormaNoninterestIncome
Noninterest income
Amount of pro forma noninterest income of combined entity as if acquisition date of business combination occurred as of beginning of period.
Schedule of Nonvested Performance-Based Units Activity [Table Text Block]
Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]
cnob_ReversalOfExpenseDueToImprovementsInExpectedCashFlows
Release of nonaccretable marks due to improvements in expected cash flows
Amount of reversal of expense due to improvements in expected cash flows.
Less: Allowance for credit losses - loans
Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest
Balance
Balance
Financial Asset, 60 to 89 Days Past Due [Member]
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest
Tenor Spread Adjustment [Member]
Amount of tenor spread adjustment.
Schedule of Cash Flow Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block]
Originated Four Years Prior
Originated Five or More Years Prior
Originated Two Years Prior
Originated Three Years Prior
Fair Value Disclosures [Text Block]
Originated Current Fiscal Year
Fair Value, by Balance Sheet Grouping [Table Text Block]
Originated One Year Prior
Supplemental disclosures of cash flow information
Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) [Table Text Block]
Derivatives Not Designated as Hedging Instruments [Table Text Block]
Revolving Loans
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Table]
Secured Overnight Financing Rate (SOFR) [Member]
us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments
Accretion of discounts and amortization of premium on available-for-sale securities
Borrowings
us-gaap_LongTermDebtFairValue
Preferred stock, liquidation preference (in dollars per share)
Payment Deferral (Month)
Loans held-for-sale
us-gaap_LoansHeldForSaleFairValueDisclosure
Legacy CNOB Plan [Member]
Represents the Legacy CNOB plan.
Loss on bank owned life insurance policy exchange
Amount of loss on bank owned life insurance policy exchange.
Legacy FLIC Plan [Member]
Represents the Legacy FLIC plan.
Collateral Held [Domain]
Liquidation value (in dollars per share)
Collateral Held [Axis]
Common Stock, No Par Value (in dollars per share)
Accumulated other comprehensive loss
us-gaap_TimeDepositMaturitiesYearThree
2028
us-gaap_TimeDepositMaturitiesYearTwo
2027
us-gaap_TimeDepositMaturitiesYearFour
2029
us-gaap_TimeDepositMaturitiesYearOne
2026
us-gaap_TimeDepositMaturitiesAfterYearFive
thereafter
us-gaap_TimeDepositMaturitiesYearFive
2030
Business Combination, Pro Forma Information [Table]
Information technology and communications
us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
Income before income tax expense
Additional paid-in capital
Segment Reporting, Policy [Policy Text Block]
Use of Estimates, Policy [Policy Text Block]
us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)
us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)
Unrealized Gain (Loss) on Investments [Table Text Block]
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]
us-gaap_PaymentsToAcquirePropertyPlantAndEquipment
Purchases of premises and equipment
Stock grants
Net shares issued in satisfaction of units earned
Collateral Pledged [Member]
us-gaap_NoninterestExpense
Total noninterest expenses
Securities issued
Debt Instrument, Face Amount
Modified
us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2
Noninterest expenses
Bank owned life insurance restructuring charge
Amount of loss from restructuring of bank owned life insurance.
Periodic Payment Reduction [Member]
Represents Periodic Payment Reduction.
Financial Asset, Not Past Due [Member]
Restricted stock grants, net of forfeitures
Net shares issued in satisfaction of units earned, shares (in shares)
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture (in shares)
Redeemable by issuer beginning
cnob_FinancingReceivablePurchasedWithCreditDeteriorationExcludingAccruedInterestAllowanceForCreditLossWriteoff
Charge-offs
Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff for loans purchased with credit deterioration. Excludes net investment in lease.
Stock grants, shares (in shares)
us-gaap_OffBalanceSheetCreditLossLiability
Balance at beginning of period
Balance at end of period
Restricted Stock Units (RSUs) [Member]
us-gaap_GoodwillPurchaseAccountingAdjustments
Goodwill, Measurement Period Adjustment
cnob_FinancingReceivableNumberOfModifications
Financing Receivable, Number of Modifications
Number of modifications for financing receivable.
Debt Instrument, Name [Domain]
Fair Value Measurement Inputs and Valuation Techniques [Table Text Block]
Maturity
us-gaap_DebtInstrumentInterestRateStatedPercentage
Debt Instrument, Interest Rate, Stated Percentage
Restricted stock grants, shares (in shares)
Depreciation
Depreciation and amortization of premises and equipment
us-gaap_DebtInstrumentInterestRateEffectivePercentage
Debt Instrument, Interest Rate, Effective Percentage
Class of Stock [Domain]
Repurchase of treasury stock, shares (in shares)
us-gaap_NoncashMergerRelatedCosts
Noncash Merger Related Costs
Schedule of Long-Term Debt Instruments [Table]
Debt Instrument [Axis]
Cash flows from operating activities
Cash flows from investing activities
us-gaap_NetCashProvidedByUsedInOperatingActivities
Net cash provided by operating activities
Cash flows from financing activities
us-gaap_NetCashProvidedByUsedInInvestingActivities
Net cash (used in) provided by investing activities
us-gaap_NetCashProvidedByUsedInFinancingActivities
Net cash provided by (used in) financing activities
Position [Axis]
Borrowings
Total FHLB borrowings
Position [Domain]
us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt
Purchases
us-gaap_LiabilitiesFairValueDisclosure
Total liabilities
us-gaap_AssetsFairValueDisclosure
Total assets
Loans, Notes, Trade and Other Receivables Disclosure [Text Block]
Long [Member]
Short [Member]
Net increase (decrease) in deposits
Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment [Member]
Operating Segments [Member]
Accounting Policies [Abstract]
Credit Loss Status [Axis]
Credit Loss Status [Domain]
US States and Political Subdivisions Debt Securities [Member]
us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss
Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss
Net loans receivable
us-gaap_TimeDepositLiabilityAboveUsInsuranceLimit
Time Deposit Liability, above US Insurance Limit
Measurement Input Type [Axis]
us-gaap_PaymentsForProceedsFromLoansAndLeases
Net (increase) decrease in loans
Income Statement [Abstract]
Nonaccretable credit marks on PCD loans
Amount, excluding accrued interest, of nonaccretable credit marks of financing receivable purchased with credit deterioration. Excludes net investment in lease.
(Reversal of) provision for credit losses - unfunded commitments
(Reversal of) provision for credit losses – unfunded commitments
Securities available-for-sale, fair value
Investment securities
Total investment securities available-for-sale, fair value
us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted
Income attributable to common stock
Total segment income
cnob_SegmentIncome
Represents the amount of segment income during the period.
us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLoss
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, after Allowance for Credit Loss
us-gaap_DeferredIncomeTaxExpenseBenefit
Deferred Income Tax Expense (Benefit)
Measurement Input, Comparability Adjustment [Member]
us-gaap_AmortizationOfDeferredLoanOriginationFeesNet
Net accretion of loans
us-gaap_TreasuryStockCommonValue
Treasury stock, at cost: 3,975,548 shares as of March 31, 2026 and 3,885,548 shares as of December 31, 2025
Treasury Stock, Common, Shares (in shares)
Measurement Input, Discount Rate [Member]
Treasury Stock, Common [Member]
Reported Value by Acquiree [Member]
Represents reported value by acquiree.
Fair Value Adjustments [Member]
Represents fair value adjustments.
Net income
Net income
Net income
Net income available to common stockholders
Net income available to common stockholders
Financial Asset, Past Due [Member]
Amortization of subordinated debentures issuance costs
Amortization of intangibles
Amortization of core deposit intangibles
Valuation Technique, Discounted Cash Flow [Member]
Derivative, amount of gain (loss) reclassified from OCI to interest income
Measurement Input Type [Domain]
Interest income on cash flow hedges
us-gaap_InterestIncomeExpenseNet
Interest Income (Expense), Operating
Net interest income
Accumulated Other Comprehensive Income (Loss) [Table]
Restricted Stock [Member]
Asset-Backed Securities [Member]
PCD Loans, fair value
Amount of gain (loss) recognized in OCI
Occupancy and equipment
Other expenses
FDIC insurance
Total purchased credit-deteriorated loans
us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationDiscountPremium
PCD Loans, discount
us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue
Increase in cash surrender value of bank owned life insurance
us-gaap_TreasuryStockValueAcquiredCostMethod
Repurchase of stock
Income on bank owned life insurance
Noninterest income
us-gaap_NoninterestIncome
Total noninterest income
Noninterest income
Measurement Basis [Axis]
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Table]
Change in estimate (decrease), weighted average grant date fair value (in dollars per share)
The weighted average fair value at for nonvested equity-based awards changes in estimate during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).
Change in estimate (decrease), units (in shares)
The number of decrease in changes in estimate made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).
cnob_NetInterestIncomeAndNoninterestIncome
Segment net interest income and noninterest income
Amount of interest income (expense) classified as operating and noninterest income.
Fair Value Hierarchy and NAV [Domain]
Net gains on sale of loans held-for-sale
Gains on sale of loans held-for-sale, net
Measurement Frequency [Domain]
Total expenses for segment assets
cnob_ExpenseForSegmentAssets
Amount of expense for segment assets.
Vesting [Axis]
Vesting [Domain]
Statement of Financial Position [Abstract]
Change in unrealized loss
Provision for credit losses – loans
Operating provision for credit losses
Income taxes
Marketing and advertising
Recoveries
Other assets
Gross write-off
Charge-offs
Fair Value, Nonrecurring [Member]
Professional and consulting
Fair Value, Recurring [Member]
us-gaap_PaymentsForRepurchaseOfCommonStock
Repurchase of treasury stock
us-gaap_IncreaseDecreaseInOtherOperatingAssets
Increase in other assets
Document Type
Document Information [Line Items]
Document Quarterly Report
us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAllowanceForCreditLossAtAcquisitionDate
PCD Loans, allowance for credit losses
Document Information [Table]
us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)
Nonvested Restricted Stock Shares Activity [Table Text Block]
Entity Interactive Data Current
ConnectOne shares entitlement (in shares)
Business Combination, Consideration Transferred, Equity Interest, Share Issued, Number of Shares (in shares)
Bank owned life insurance
Document Transition Report
us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding
Weighted average common and equivalent shares outstanding (in shares)
us-gaap_IncreaseDecreaseOfRestrictedInvestments
Net redemptions of restricted investment in bank stocks
Earnings per common share
us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted
Diluted EPS (in dollars per share)
us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic
Basic EPS (in dollars per share)
Incremental shares from assumed conversions of options, performance units and restricted shares (in shares)
us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss
Net income
us-gaap_WeightedAverageNumberOfSharesOutstandingBasic
Weighted average common shares outstanding (in shares)
Derivative Instrument [Axis]
Basic (in dollars per share)
Earnings Per Share, Basic, by Common Class, Including Two-Class Method [Table]
us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage
Nonaccrual loans without ACL
Financial Asset Acquired with Credit Deterioration [Member]
Total Nonaccrual loans
Nonaccrual
Positions
Acquired with deteriorated credit quality
Amount of allowance for credit loss (income) on financing receivable evaluated on individual basis. Excludes financing receivable evaluated on collective basis.
Interest-bearing
Debt Securities, Available-for-Sale [Table Text Block]
us-gaap_Deposits
Total deposits
Deposits:
Deposit Liabilities Disclosures [Text Block]
Amortization on borrowings, net
Noninterest-bearing
Core deposit intangibles
Document Fiscal Period Focus
Pledging Purpose [Axis]
Document Fiscal Year Focus
Pledging Purpose [Domain]
Amendment Flag
us-gaap_DepositsReceivedForSecuritiesLoanedAtCarryingValue
Deposits Received for Securities Loaned, at Carrying Value
Common Stock [Member]
us-gaap_FinancingReceivableUnamortizedLoanCommitmentOriginationFeeAndPremiumDiscount
Net deferred loan fees
Goodwill
Goodwill
Decrease in other liabilities
us-gaap_RestructuringCharges
Restructuring Charges
Document Period End Date
Residential Portfolio Segment [Member]
Legal Entity [Axis]
Business Combination, Consideration Transferred, Equity Interest [Table]
Dividends
Interest income
us-gaap_InterestAndDividendIncomeOperating
Total interest income
Consumer Portfolio Segment [Member]
SBA Loans [Member]
Relating to SBA loans.
Commercial Real Estate Portfolio Segment [Member]
Business Combination, Consideration Transferred, Equity Interest, Type [Domain]
cnob_FinancingReceivableAllowanceForCreditLossReversalIndividuallyEvaluated
Acquired with deteriorated credit quality
Amount of allowance for credit loss (reversal) on financing receivable evaluated on individual basis. Excludes financing receivable evaluated on collective basis.
Commercial Portfolio Segment [Member]
Business Combination [Domain]
Derivative, fair value
us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
Individually analyzed, gross loans
Entity File Number
us-gaap_DerivativeFixedInterestRate
Derivative, Fixed Interest Rate
us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment
Collectively evaluated, gross loans
Entity Tax Identification Number
Business Combination [Axis]
Net unrealized holding (losses) gains on available-for-sale securities arising during the period
Collectively evaluated, allowance for credit loss
us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
Temporarily impaired securities, unrealized losses, less than 12 months
Entity [Domain]
us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
Temporarily impaired securities, unrealized losses, 12 months or longer
Entity Central Index Key
Entity Registrant Name
Doubtful [Member]
Entity Current Reporting Status
Business Combination [Table]
Amount of gain recognized in other noninterest income
Special Mention [Member]
Substandard [Member]
Entity Incorporation, State or Country Code
Business Combination, Pro Forma Information [Table Text Block]
Pass [Member]
Current Fiscal Year End Date
us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFinancialAssets
Financial assets
us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents
Cash and cash equivalents
us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsMarketableSecurities
Available-for-sale Securities
Entity Filer Category
Cash dividend declared on preferred stock, per share (in dollars per share)
us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets
Total assets acquired
Entity Shell Company
us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities
Total liabilities assumed
Entity Emerging Growth Company
Derivative, notional amount
Entity Small Business
us-gaap_DerivativeNumberOfInstrumentsHeld
Derivative, Number of Instruments Held
Non-PCD Loans, unpaid principal balance
Valuation Approach and Technique [Axis]
us-gaap_BusinessCombinationAcquiredReceivablesEstimatedUncollectible
Non-PCD Loans, allowance for credit losses
us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill
Core deposit intangible
us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet
Net assets acquired
Hedging Designation [Domain]
Non-PCD Loans, fair value
us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets
Other assets
Fair value asset
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]
us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment
Premises and equipment, net
Loans Modified, Gross
The gross amount of loans modified during the period.
Preferred dividends
Interest expense
us-gaap_InterestExpenseBorrowings
Borrowings
Interest-bearing deposits with banks
Derivative Instruments and Hedging Activities Disclosure [Text Block]
Valuation Approach and Technique [Domain]
Other segment items*
us-gaap_SegmentReportingOtherItemAmount
Valuation, Market Approach [Member]
us-gaap_DerivativeLiabilityNotionalAmount
Derivative Liability, Notional Amount
Total purchase price consideration
us-gaap_BusinessCombinationConsiderationTransferred1
Business Combination, Consideration Transferred
Total purchase price consideration
Deposits
Entity Address, State or Province
us-gaap_PaymentsForOriginationAndPurchasesOfLoansHeldForSale
Loans originated for resale
Entity Address, City or Town
Retained earnings
Interest expense
us-gaap_InterestExpenseOperating
Total interest expense
Entity Address, Address Line One
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]
City Area Code
Due after one year through five years, amortized cost
us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation
Share redemption for tax withholdings on performance units, deferred stock units earned and restricted stock units
us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther
Other liabilities
Due after five years through ten years, amortized cost
Local Phone Number
Due in one year or less, amortized cost
Entity Address, Postal Zip Code
Derivative [Table]
Preferred Stock [Member]
us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesLongTermDebt
Borrowings
Securities available-for-sale, without single maturity date, fair value
Title of 12(b) Security
Security Exchange Name
Due after five years through ten years, fair value
Trading Symbol
Due after ten years, fair value
Due in one year or less, fair value
Due after one year through five years, fair value
Securities available-for-sale, input
us-gaap_DebtSecuritiesAvailableForSaleMeasurementInput
Due after ten years, amortized cost
Class of Stock [Axis]
Securities available-for-sale, without single maturity date, amortized cost
Variable Rate [Axis]
Class of Financing Receivable [Axis]
Variable Rate [Domain]
Class of Financing Receivable [Domain]
Entity Common Stock, Shares Outstanding
Earnings Per Share [Text Block]
Cash Flow Hedging [Member]
Preferred stock, par value (in dollars per share)
Hedging Designation [Axis]
us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLossFeeAndLoanInProcess
Gross loans
Internal Credit Assessment [Axis]
Weighted average common shares outstanding, including participating securities (in shares)
Other Debt Obligations [Member]
Merger expenses and restructuring charges
Business Combination, Acquisition-Related Cost, Expense
Not Designated as Hedging Instrument [Member]
us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
Principal paydowns
Scenario [Axis]
us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss
Net interest income after provision for credit losses
Reclassification out of Accumulated Other Comprehensive Income [Domain]
Scenario [Domain]
Interest Rate Swap With Offsetting Company [Member]
Relating to interest rate swap with offsetting company.
Reclassification out of Accumulated Other Comprehensive Income [Member]
Interest Rate Swap with Borrower [Member]
Relating to interest rate swap with borrower.
Reclassification out of Accumulated Other Comprehensive Income [Axis]
Deferred Compensation Arrangement with Individual, Share-Based Payment [Table]
Investments Classified by Contractual Maturity Date [Table Text Block]
Internal Credit Assessment [Domain]
Interest on federal funds sold and other short-term investments
Total fair value of stock consideration issued
Taxable
Other liabilities
Individually analyzed, allowance for credit loss
Basis of Accounting, Policy [Policy Text Block]
Tax-exempt
Hedging Relationship [Axis]
Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]
cnob_DefinedBenefitPlanEmployersMatchingContributionVestingPeriod
Defined Benefit Plan, Employers Matching Contribution, Vesting Period (Year)
Period of vesting for employer's matching contributions to a defined benefit plan.
cnob_TimeDepositMaturities
Time deposits (before net discount)
Sub-Total
cnob_TimeDepositMaturitiesFairValuePremium
Fair value discount
Fair value premium.
Derivative Contract [Domain]
Schedule Of Time Deposits [Table Text Block]
Tabular disclosure of the schedule of time deposits.
Accelerated Share Repurchases [Table]
cnob_DefinedBenefitPlanMinimumAgeOfEmployee
Defined Benefit Plan, Minimum Age of Employee
Minimum age of employee to participate in the defined benefit plan.
cnob_DefinedBenefitPlanEmployerMatchingContributionPercentOfEmployeesGrossPay
Defined Benefit Plan, Employer Matching Contribution, Percent of Employees' Gross Pay
Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined benefit plan.
cnob_DefinedBenefitPlanMinimumService
Defined Benefit Plan, Minimum Service (Month)
Minimum service period of employee to participate in defined benefit plan.
Cash and due from banks
Assets
us-gaap_Assets
Total assets
Deposit, loan and other income
Amount of deposit, loan and other income.
Designated as Hedging Instrument [Member]
us-gaap_CashAndCashEquivalentsAtCarryingValue
Cash and cash equivalents
Financing Receivable, Modified, Past Due [Table Text Block]
Modified
Modified, percentage
Interest and dividends on investment securities:
Diluted (in dollars per share)
us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay
Interest Rate Cap [Member]
cnob_FinancingReceivableModifiedSubsequentDefaultNumberOfContracts
Financing Receivable, Modified, Subsequent Default, Number of Contracts
Number of financing receivable contracts modified within previous 12 months, with subsequent payment default.
Weighted Average Interest Rate Reduction
Cash consideration paid
Financing Receivable, Modified, Past Due [Table]
Derivatives
us-gaap_InterestRateDerivativeAssetsAtFairValue
Restricted investments in bank stocks
us-gaap_RestrictedInvestmentsAtFairValue
Asset Class [Domain]
us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation
Share redemption for tax withholdings
Weighted Average Term Extension (Month)
LIBOR - London Interbank Offered Rate [Member]
Interest rate at which a bank borrows funds from other banks in the London interbank market.
Accounts and Financing Receivables [Table]
Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]
Financial Asset, 30 to 89 Days Past Due [Member]
Financial asset more than 29 days past due but fewer than 90 days past due.
Derivatives - interest rate contracts
us-gaap_InterestRateDerivativeLiabilitiesAtFairValue
Accrued interest receivable
us-gaap_InterestReceivable
Interest paid on deposits and borrowings
Interest Rate Swap [Member]
Schedule of Long-Term Debt Instruments [Table Text Block]
Business Combination [Table Text Block]
Gross write-off, five years prior
Investment in restricted stock, at cost
Gross write-off, revolving
Gross write-off, three years prior
Gross write-off, four years prior
Gross write-off, one year prior
Gross write-off, two years prior
Gross write-off, current year
Business Combination [Text Block]
Hedging Relationship [Domain]
Nature of Operations [Policy Text Block]
Disclosure of accounting policy for nature of operations.
Balance
Total stockholders’ equity
Balance
Balance
Weighted average participating securities (in shares)
Number of shares of common stock attributable to participating securities.
cnob_DebtSecuritiesAvailableforsaleHoldingGreaterThan10PercentOfEquity
Debt Securities, Available-for-sale, Holding Greater than 10 Percent of Equity
The number of investments in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) that are greater than 10% of equity.
Forfeited/cancelled/expired, weighted average grant date fair value (in dollars per share)
Forfeited/cancelled/expired, weighted average grant date fair value (in dollars per share)
cnob_AccretionOnBankPremises
Accretion on bank premises
The amount of accretion on bank premises.
Depositary Shares [Member]
Represents depositary shares.
us-gaap_PaymentsOfDividendsCommonStock
Cash dividends paid on common stock
Commenced Fixed Interest Rate Swaps [Member]
Represents fixed interest rate swaps which have already commenced.
Schedule of Loans Held-for-sale [Table Text Block]
Tabular disclosure of loans held-for-sale.
Nature of Operation, Product Information, Concentration of Risk [Table]
Nonaccrual loans with ACL
Amortized cost of financing receivable on nonaccrual status with allowance for credit loss. Excludes net investment in lease.
Commercial Construction Portfolio Segment [Member]
Portfolio segment of the company's total financing receivables related to commercial construction receivables.
Right of use operating lease assets
us-gaap_RepaymentsOfFederalHomeLoanBankBorrowings
Repayment of FHLB borrowings
us-gaap_PaymentsOfDividendsPreferredStockAndPreferenceStock
Cash dividends on preferred stock
us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss
ecd_Rule10b51ArrTrmntdFlag
Rule 10b5-1 Arrangement Terminated [Flag]
ecd_Rule10b51ArrAdoptedFlag
Rule 10b5-1 Arrangement Adopted [Flag]
COMMITMENTS AND CONTINGENCIES