Note 19 - Fair Values of Financial Instruments - Assets at Fair Value (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Available-for-sale Securities, fair value disclosure	$ 24,399,881	$ 31,499,132
Assets, fair value disclosure	45,427,790	51,688,516
Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument [Member]
Derivative, fair value	183,000
Forward Contracts [Member] \| Not Designated as Hedging Instrument [Member]
Derivative, fair value	15,820	0
Fair Value, Inputs, Level 1 [Member]
Assets, fair value disclosure	0	0
Fair Value, Inputs, Level 2 [Member]
Assets, fair value disclosure	39,990,818	45,720,295
Fair Value, Inputs, Level 3 [Member]
Assets, fair value disclosure	5,436,972	5,968,221
Fair Value, Measurements, Recurring [Member]
Loans held for sale, fair value disclosure	15,423,670
Loans held-for-sale, fair value disclosure	15,423,670
Fair Value, Measurements, Recurring [Member] \| Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLCs, fair value disclosure	183,087
Fair Value, Measurements, Recurring [Member] \| Forward Contracts [Member] \| Not Designated as Hedging Instrument [Member]
Derivative, fair value	(15,820)
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLCs, fair value disclosure	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Forward Contracts [Member] \| Not Designated as Hedging Instrument [Member]
Derivative, fair value	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLCs, fair value disclosure	183,087
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Forward Contracts [Member] \| Not Designated as Hedging Instrument [Member]
Derivative, fair value	(15,820)
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans held for sale, fair value disclosure	0
Loans held-for-sale, fair value disclosure	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLCs, fair value disclosure	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Forward Contracts [Member] \| Not Designated as Hedging Instrument [Member]
Derivative, fair value	0
Fair Value, Measurements, Nonrecurring [Member]
Loans held for sale, fair value disclosure		14,221,163
Impaired loans, fair value disclosure	5,436,972	5,968,221
Loans held-for-sale, fair value disclosure		14,221,163
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Loans held for sale, fair value disclosure	0	0
Impaired loans, fair value disclosure	0	0
Loans held-for-sale, fair value disclosure	0	0
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Loans held for sale, fair value disclosure	15,423,670	14,221,163
Impaired loans, fair value disclosure	0	0
Loans held-for-sale, fair value disclosure	15,423,670	14,221,163
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans held for sale, fair value disclosure		0
Impaired loans, fair value disclosure	5,436,972	5,968,221
Loans held-for-sale, fair value disclosure		0
Collateralized Mortgage Backed Securities [Member]
Available-for-sale Securities, fair value disclosure	20,768,592	27,128,397
Collateralized Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Available-for-sale Securities, fair value disclosure	20,768,592	27,128,396
Collateralized Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale Securities, fair value disclosure	0	0
Collateralized Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale Securities, fair value disclosure	20,768,592	27,128,396
Collateralized Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale Securities, fair value disclosure	0	0
US Government Agencies Debt Securities [Member]
Available-for-sale Securities, fair value disclosure	1,957,783	2,525,736
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Available-for-sale Securities, fair value disclosure	1,957,783	2,525,737
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale Securities, fair value disclosure	0	0
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale Securities, fair value disclosure	1,957,783	2,525,737
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale Securities, fair value disclosure	0	0
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale Securities, fair value disclosure	1,673,506	1,844,999
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Available-for-sale Securities, fair value disclosure	1,673,506	1,844,999
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale Securities, fair value disclosure	0	0
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale Securities, fair value disclosure	1,673,506	1,844,999
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale Securities, fair value disclosure	$ 0	$ 0

Represents the fair value of impaired loans.

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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.

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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, before 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 elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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