Subsequent Event	12 Months Ended
Dec. 31, 2019
Subsequent Events [Abstract]
Subsequent Event	Note 26 – Subsequent Event On January 2, 2019, Bancorp of New Jersey, Inc. merged with and into ConnectOne Bank, with ConnectOne Bank as the surviving bank. As a result of the merger, the Company acquired approximately $0.8 billion in loans, assumed approximately $0.8 billion in deposits and acquired nine branch offices all located in Bergen County, New Jersey. Subject to the allocation and proration procedures set forth in the merger agreement, shareholders of BNJ common stock had the right to elect, with respect to each share of BNJ common stock, to receive either (i) $16.25 in cash or (ii) 0.780 of a share of CNOB common stock (plus cash in lieu of any fractional shares of CNOB common stock to which such holder would otherwise be entitled). The allocation and proration procedures set forth in the merger agreement required that approximately 20% of the shares of BNJ common stock be converted into cash and the remaining approximately 80% of BNJ common shares be converted into shares of ConnectOne common stock. Given the initial accounting for this business combination is incomplete, management is not yet able to disclose the preliminary fair value of the assets acquired and liabilities assumed.

Subsequent Event

12 Months Ended

Dec. 31, 2019

Note 26 – Subsequent Event

On January 2, 2019, Bancorp of New Jersey, Inc. merged with and into ConnectOne Bank, with ConnectOne Bank as the surviving bank. As a result of the merger, the Company acquired approximately $0.8 billion in loans, assumed approximately $0.8 billion in deposits and acquired nine branch offices all located in Bergen County, New Jersey. Subject to the allocation and proration procedures set forth in the merger agreement, shareholders of BNJ common stock had the right to elect, with respect to each share of BNJ common stock, to receive either (i) $16.25 in cash or (ii) 0.780 of a share of CNOB common stock (plus cash in lieu of any fractional shares of CNOB common stock to which such holder would otherwise be entitled). The allocation and proration procedures set forth in the merger agreement required that approximately 20% of the shares of BNJ common stock be converted into cash and the remaining approximately 80% of BNJ common shares be converted into shares of ConnectOne common stock. Given the initial accounting for this business combination is incomplete, management is not yet able to disclose the preliminary fair value of the assets acquired and liabilities assumed.