Note 7 - Federal Home Loan Bank of Indianapolis Advances (Details Textual) - USD ($)	Mar. 31, 2017	Dec. 31, 2016
Long-term Federal Home Loan Bank Advances	$ 205,000,000	$ 175,000,000
Line of Credit Facility, Maximum Borrowing Capacity	541,000,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 336,000,000
Federal Home Loan Bank of Indianapolis [Member]
Long-term Federal Home Loan Bank Advances		$ 175,000,000
Federal Home Loan Bank of Indianapolis [Member] \| Minimum [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Interest Rate at Period End	1.04%	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	2.39%	2.11%
Federal Home Loan Bank of Indianapolis [Member] \| Weighted Average [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate	1.59%	1.48%

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64702-112823

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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