Note 1 - Basis of Presentation and Critical Accounting Policies (Details Textual) - USD ($)	Dec. 18, 2015	Jan. 29, 2015
Stock Issued During Period, Shares, New Issues (in shares)		13,100,360
Proceeds from Issuance of Common Stock, Net		$ 117,600,000
Proceeds from Issuance Initial Public Offering		58,400,000
Employee Stock Ownership Plan (ESOP), Issued, Percentage of Common Stock Issued	8.00%
Stock Issued During Period, Shares, Employee Stock Ownership Plan (in shares)	1,048,029
First Federal Community Foundation [Member]
Payments for Contributions to Charity		$ 400,000
Contribution of Nonmonetary Assets to Charitable Organization [Member] \| First Federal Community Foundation [Member]
Stock Issued During Period, Shares, New Issues (in shares)		933,360
IPO [Member]
Stock Issued During Period, Shares, New Issues (in shares)		12,167,000
Shares Issued, Price Per Share (in dollars per share)		$ 10
Proceeds from Issuance of Common Stock		$ 121,700,000

The percentage of common stock issued that employee stock ownership plan (ESOP) shares are issued.

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The amount of cash outflow for contributions to charity.

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The cash inflow from the additional capital contribution to the entity, net of issuance costs.

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- Definition

The cash inflow associated with the amount received from entity's first offering of stock to the public.

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Per share or per unit amount of equity securities issued.

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Number of shares of capital stock issued (purchased by employees) in connection with an employee stock ownership plan.

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Number of new stock issued during the period.

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