Note 18 - Commitments and Contingencies (Details Textual) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Loans Receivable Held-for-sale, Net, Not Part of Disposal Group, Mortgage	$ 645,001	$ 1,135,500
Loans Sold with Recourse Provisions	300,000	916,900
Cash, Uninsured Amount	42,900,000	48,500,000
Money Market Funds, at Carrying Value	136,032,073	117,985,224
Standby Letters of Credit [Member]
Other Commitment	17,283,025	15,697,469
Commitments to Extend Credit [Member]
Other Commitment	$ 791,550,060	$ 666,778,085

Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

No definition available.

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