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- References

No definition available.

Name:	cnob_FinancialLiabilitiesAbstract
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Period Type:	duration

Fair value as of the balance sheet date of interest-bearing deposit liabilities.

No definition available.

Name:	cnob_InterestBearingDepositsFairValueDisclosure
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Fair value as of the balance sheet date of non interest-bearing deposit liabilities.

No definition available.

Name:	cnob_NonInterestBearingDepositsFairValueDisclosure
Namespace Prefix:	cnob_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Fair value portion of accrued expenses.

Name:	us-gaap_AccruedLiabilitiesFairValueDisclosure
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Period Type:	instant

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Name:	us-gaap_AdvancesFromFederalHomeLoanBanks
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

No definition available.

Name:	us-gaap_AvailableForSaleSecurities
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Name:	us-gaap_CashAndCashEquivalentsAtCarryingValue
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

No definition available.

Name:	us-gaap_CashAndCashEquivalentsFairValueDisclosure
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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Name:	us-gaap_DerivativeFairValueOfDerivativeLiability
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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Name:	us-gaap_DerivativeLiabilities
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Period Type:	instant

Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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Name:	us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations
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Amount of investment in debt security measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Name:	us-gaap_HeldToMaturitySecuritiesFairValue
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The aggregate of all domestic and foreign interest-bearing deposit liabilities.

Name:	us-gaap_InterestBearingDepositLiabilities
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Amount of interest payable on debt, including, but not limited to, trade payables.

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Name:	us-gaap_InterestPayableCurrentAndNoncurrent
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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

Name:	us-gaap_InterestReceivable
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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Name:	us-gaap_LoansAndLeasesReceivableNetReportedAmount
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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Name:	us-gaap_LoansReceivableFairValueDisclosure
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Amount, before valuation allowance, of financing receivable classified as held-for-sale.

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Name:	us-gaap_LoansReceivableHeldForSaleAmount
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

No definition available.

Name:	us-gaap_LongTermDebtFairValue
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The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

Name:	us-gaap_NoninterestBearingDepositLiabilities
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

Name:	us-gaap_OtherBorrowings
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Fair value portion of receivables, including, but not limited to, trade account receivables, note receivables, and loan receivables.

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Name:	us-gaap_ReceivablesFairValueDisclosure
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Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

No definition available.