Floating interest rate on subordinated debentures.

No definition available.

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Namespace Prefix:	cnob_
Data Type:	num:percentItemType
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- Definition

Percentage rate added to LIBOR.

+ References

No definition available.

+ Details

Name:	cnob_PercentageRateAddedToLibor
Namespace Prefix:	cnob_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Cutstom Element.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

Value of subordinated debentures received by Trust.

+ References

No definition available.

+ Details

Name:	cnob_ValueOfSubordinatedDebenturesReceived
Namespace Prefix:	cnob_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_DebtInstrumentAxis=cnob_FixedToFloatingRateSubordinatedNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_DebtInstrumentAxis=cnob_SubordinatedDebtFromTrustMember
Namespace Prefix:
Data Type:	na
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Period Type:

Subordinated Debentures (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Subordinated Debentures (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2016	Dec. 31, 2015
Subordinated Debentures (Details) [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		5.75%	3.75%
Fixed-to-floating Rate Subordinated Notes [Member]
Subordinated Debentures (Details) [Line Items]
Proceeds from Issuance of Debt	$ 50,000
Debt Instrument, Term	5 years
Debt Instrument, Maturity Date	Jul. 01, 2025
Debt Instrument, Interest Rate, Stated Percentage	5.75%
Debt Instrument, Description of Variable Rate Basis	three-month LIBOR rate plus 393 basis points
Subordinated Debt from Trust [Member]
Subordinated Debentures (Details) [Line Items]
Value of subordinated debentures received by Trust		$ 5,000
Percentage Rate Added to Libor		2.85%
Floating interest rate on subordinated debentures		3.74%
Proceeds from Issuance of Debt		$ 5,200
Debt Instrument, Maturity Date		Jan. 23, 2034
Debt Instrument, Basis Spread on Variable Rate		3.93%
Unamortized Debt Issuance Cost		$ 621