Note 7 - Deposits (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Note 7 - Deposits (Details) [Line Items]
Time Deposits, $250,000 or More	$ 235,565,570	$ 230,925,385
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	480,466,274	499,084,047
Federal Home Loan Bank of Des Moines [Member]
Note 7 - Deposits (Details) [Line Items]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	45,000,000	15,000,000
Letters of Credit Outstanding, Amount	0	0
Federal Home Loan Bank of Chicago [Member]
Note 7 - Deposits (Details) [Line Items]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	8,000,000
Letters of Credit Outstanding, Amount	$ 0	$ 0