Note 7 - Federal Home Loan Bank of Indianapolis Advances (Details Textual) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Long-term Federal Home Loan Bank Advances, Total	$ 230,000,000	$ 220,000,000
Line of Credit Facility, Maximum Borrowing Capacity	657,000,000
Line of Credit Facility, Remaining Borrowing Capacity	427,000,000
Federal Home Loan Bank of Indianapolis [Member]
Long-term Federal Home Loan Bank Advances, Total	$ 230,000,000	$ 220,000,000
Federal Home Loan Bank of Indianapolis [Member] \| Minimum [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Interest Rate at Period End	1.20%	1.04%
Federal Home Loan Bank of Indianapolis [Member] \| Maximum [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Interest Rate at Period End	3.10%	2.39%
Federal Home Loan Bank of Indianapolis [Member] \| Weighted Average [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate	1.94%	1.72%

Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
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States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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