Subsequent Events	12 Months Ended
Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	Note 26 – Subsequent Event On January 2, 2019, Greater Hudson Bank merged with and into ConnectOne Bank, with ConnectOne Bank as the surviving bank. As a result of the merger, the Company acquired approximately $0.4 billion in loans, assumed approximately $0.4 billion in deposits and acquired seven branch offices located in Rockland, Orange and Westchester Counties, New York. The assets and liabilities acquired will be recorded at fair value as of the acquisition date. Each outstanding share of Greater Hudson Bank common stock was exchanged for 0.245 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.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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