Note 7 - Fair Value - Assets Measured At Fair Value On a Recurring and Nonrecurring Basis (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Securities available for sale, fair value	$ 255,323,442	$ 272,907,907
Fair Value, Measurements, Recurring [Member]
Assets Fair Value	263,072,129	277,811,845
Liabilities Fair Value	6,837,887	4,397,238
Fair Value, Measurements, Recurring [Member] \| Interest rate cap
Interest rate	703,467	506,700
Fair Value, Measurements, Recurring [Member] \| Interest rate swap
Interest rate	7,045,220	4,397,238
Derivative Liabilities	6,837,887	4,397,238
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Assets Fair Value		1,028
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Assets Fair Value	263,072,129	277,810,817
Liabilities Fair Value	6,837,887	4,397,238
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest rate cap
Interest rate	703,467	506,700
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest rate swap
Interest rate	7,045,220	4,397,238
Derivative Liabilities	6,837,887	4,397,238
Fair Value, Measurements, Nonrecurring [Member]
Assets Fair Value	26,580,154	23,615,310
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Assets Fair Value	26,580,154	23,615,310
US Government Agencies Debt Securities [Member]
Securities available for sale, fair value	36,491,749	38,096,534
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale, fair value	36,491,749	38,096,534
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale, fair value	36,491,749	38,096,534
Residential Mortgage Backed Securities [Member]
Securities available for sale, fair value	155,732,596	163,301,304
Residential Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale, fair value	155,732,596	163,301,304
Residential Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale, fair value	155,732,596	163,301,304
US States and Political Subdivisions Debt Securities [Member]
Securities available for sale, fair value	58,904,207	66,625,496
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale, fair value	58,904,207	66,625,496
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale, fair value	58,904,207	66,625,496
Other Securities [Member]
Securities available for sale, fair value	4,194,890	4,884,573
Other Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale, fair value	4,194,890	4,884,573
Other Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale, fair value		1,028
Other Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale, fair value	4,194,890	4,883,545
Impaired Loans Leases [Member]
Assets Fair Value	13,400,072	8,972,337
Impaired Loans Leases [Member] \| Fair Value, Measurements, Nonrecurring [Member]
Assets Fair Value	13,400,072	8,972,337
Impaired Loans Leases [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Assets Fair Value	13,400,072	8,972,337
Other Real Estate Owned [Member]
Assets Fair Value	13,180,082	14,642,973
Other Real Estate Owned [Member] \| Fair Value, Measurements, Nonrecurring [Member]
Other Real Estate Owned Fair Value	13,180,082	14,642,973
Other Real Estate Owned [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Other Real Estate Owned Fair Value	$ 13,180,082	$ 14,642,973

The fair value of other real estate owned.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

No definition available.

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Fair value, after the effects of master netting arrangements, of a financial asset or other 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. Includes assets not subject to a master netting arrangement and not elected to be offset.

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-Publisher FASB
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Fair value, after the effects of master netting arrangements, of a 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. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

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