Note 8 - Derivative - Interest Rate Swap Agreement - Fair Value Hedge (Details) - USD ($)	Sep. 30, 2017	Mar. 31, 2017
Commercial real estate loan, principal amount	$ 365,759,226	$ 336,738,383
Loans and Leases [Member] \| Offsetting Commercial Real Estate Loan by Interest Rate Swap [Member]
Derivative notional amount
Commercial real estate loan, principal amount	3,134,403	3,175,044
Commercial real estate loan, fair value	3,171,879	3,201,691
Other Liabilities [Member] \| Interest Rate Swap [Member]
Derivative notional amount	3,134,403	3,175,044
Derivative fair value	$ 37,476	$ 26,647

Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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Fair value, after offset of derivative asset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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