Note 5 - Fair Value - Assets Measured At Fair Value on a Recurring and Nonrecurring Basis (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Securities available for sale, fair value	$ 259,954,422	$ 251,113,139
Impaired loans or leases	23,722,953	18,788,073
Fair Value, Inputs, Level 1 [Member]
Impaired loans or leases
Fair Value, Inputs, Level 2 [Member]
Impaired loans or leases
Fair Value, Inputs, Level 3 [Member]
Impaired loans or leases	23,722,953	18,788,073
Fair Value, Measurements, Recurring [Member]
Assets Fair Value	262,947,951	254,027,947
Liabilities Fair Value	2,603,002	2,338,281
Fair Value, Measurements, Recurring [Member] \| Interest Rate Cap [Member]
Derivative Assets	390,527	576,527
Fair Value, Measurements, Recurring [Member] \| Interest Rate Swap [Member]
Derivative Assets	2,603,002	2,338,281
Derivative Liabilites	2,603,002	2,338,281
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Assets Fair Value	1,017	1,361
Liabilities Fair Value
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Interest Rate Cap [Member]
Derivative Assets
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Interest Rate Swap [Member]
Derivative Assets
Derivative Liabilites
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Assets Fair Value	262,946,934	254,026,586
Liabilities Fair Value	2,603,002	2,338,281
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Cap [Member]
Derivative Assets	390,527	576,527
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Derivative Assets	2,603,002	2,338,281
Derivative Liabilites	2,603,002	2,338,281
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Assets Fair Value
Liabilities Fair Value
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Interest Rate Cap [Member]
Derivative Assets
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Interest Rate Swap [Member]
Derivative Assets
Derivative Liabilites
US Government Agencies Debt Securities [Member]
Securities available for sale, fair value	39,340,168	46,083,607
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale, fair value	39,340,168	46,083,607
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale, fair value
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale, fair value	39,340,168	46,083,607
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale, fair value
Residential Mortgage Backed Securities [Member]
Securities available for sale, fair value	158,968,509	147,702,127
Residential Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale, fair value	158,968,509	147,702,127
Residential Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale, fair value
Residential Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale, fair value	158,968,509	147,702,127
Residential Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale, fair value
US States and Political Subdivisions Debt Securities [Member]
Securities available for sale, fair value	56,763,060	52,604,426
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale, fair value	56,763,060	52,604,426
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale, fair value
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	56,763,060	52,604,426
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale, fair value
Other Securities [Member]
Securities available for sale, fair value	4,882,685	4,722,979
Other Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Securities available for sale, fair value	4,882,685	4,722,979
Other Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available for sale, fair value	1,017	1,361
Other Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available for sale, fair value	4,881,668	4,721,618
Other Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available for sale, fair value
Impaired Loans Leases [Member]
Impaired loans or leases	18,177,320	12,823,121
Impaired Loans Leases [Member] \| Fair Value, Inputs, Level 1 [Member]
Impaired loans or leases
Impaired Loans Leases [Member] \| Fair Value, Inputs, Level 2 [Member]
Impaired loans or leases
Impaired Loans Leases [Member] \| Fair Value, Inputs, Level 3 [Member]
Impaired loans or leases	18,177,320	12,823,121
Other Real Estate Owned [Member]
Impaired loans or leases	5,545,633	5,964,952
Other Real Estate Owned [Member] \| Fair Value, Inputs, Level 1 [Member]
Impaired loans or leases
Other Real Estate Owned [Member] \| Fair Value, Inputs, Level 2 [Member]
Impaired loans or leases
Other Real Estate Owned [Member] \| Fair Value, Inputs, Level 3 [Member]
Impaired loans or leases	$ 5,545,633	$ 5,964,952

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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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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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Fair value of financial and nonfinancial obligations.

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