CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Cash dividends declared on common stock (in Dollars per share)	$ 0.075	$ 0.300
Exercise of stock options, shares	110,500	100,911
Exercise of stock options, tax benefits (in Dollars)	$ 165	$ 282
Stock issued in acquisition		13,221,152
Options acquired acquisition		783,732cnob_OptionsAcquiredAcquisition
Granted restricted stock	59,466
Common Stock [Member]
Stock issued in acquisition		13,221,152
Options acquired acquisition		783,732
Additional Paid-in Capital [Member]
Exercise of stock options, shares	110,500	100,911
Exercise of stock options, tax benefits (in Dollars)	165	282
Retained Earnings [Member]
Cash dividends declared on common stock (in Dollars per share)	$ 0.075	$ 0.300
Treasury Stock [Member]
Exercise of stock options, shares	110,500	100,911
Exercise of stock options, tax benefits (in Dollars)		$ 282

Issuance of restricted stock award shares.

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No definition available.

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Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Number of share options (or share units) exercised during the current period.

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