Note 22 - Parent Company Only Financial Information - Condensed Statements of Financial Condition (Details) (Parentheticals) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Treasury stock, shares (in shares)	2,942,329	2,897,691
Holding Company [Member]
Other securities at fair value pursuant to fair value option	$ 1,110	$ 1,019
Treasury stock, shares (in shares)	2,942,329	2,897,691

This element represents the portion of the balance sheet assertion valued at fair value pursuant to the fair value option by the entity. Additionally, this element may be used in connection with the fair value option 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. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities, except for mortgage-backed securities, neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant