Note 7 - Fair Values of Financial Instruments - Assets at Fair Value (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017
Available-for-sale Securities, fair value disclosure	$ 26,095,660	$ 24,399,881
Assets, fair value disclosure	47,247,308	45,427,790
Fair Value, Inputs, Level 1 [Member]
Assets, fair value disclosure	0	0
Fair Value, Inputs, Level 2 [Member]
Assets, fair value disclosure	41,291,946	39,807,731
Fair Value, Inputs, Level 3 [Member]
Assets, fair value disclosure	5,955,362	5,620,059
Fair Value, Measurements, Recurring [Member]
Loans held for sale, fair value disclosure	15,260,895
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans held for sale, fair value disclosure	0
Fair Value, Measurements, Nonrecurring [Member]
Loans held for sale, fair value disclosure		15,423,670
Impaired loans, fair value disclosure	5,479,627	5,436,972
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
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Loans held for sale, fair value disclosure	15,260,895	15,423,670
Impaired loans, fair value disclosure	0	0
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans held for sale, fair value disclosure		0
Impaired loans, fair value disclosure	5,479,627	5,436,972
Asset-backed Securities [Member]
Available-for-sale Securities, fair value disclosure	22,655,713	20,768,592
Asset-backed Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Available-for-sale Securities, fair value disclosure	22,655,713	20,768,592
Asset-backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale Securities, fair value disclosure	0	0
Asset-backed Securities [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale Securities, fair value disclosure	22,655,713	20,768,592
Asset-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	1,780,336	1,957,783
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Available-for-sale Securities, fair value disclosure	1,780,336	1,957,783
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	1,780,336	1,957,783
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	1,659,611	1,673,506
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Available-for-sale Securities, fair value disclosure	1,659,611	1,673,506
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	1,659,611	1,673,506
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
Interest Rate Lock Commitments [Member] \| Fair Value, Measurements, Recurring [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLCs, fair value disclosure	475,735	183,087
Interest Rate Lock Commitments [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLCs, fair value disclosure	0	0
Interest Rate Lock Commitments [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLCs, fair value disclosure		0
Interest Rate Lock Commitments [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLCs, fair value disclosure	475,735	183,087
Forward Contracts [Member] \| Fair Value, Measurements, Recurring [Member] \| Not Designated as Hedging Instrument [Member]
Derivative forward commitments, fair value disclosure	(64,609)	(15,820)
Forward Contracts [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative forward commitments, fair value disclosure	0	0
Forward Contracts [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative forward commitments, fair value disclosure	(64,609)	(15,820)
Forward Contracts [Member] \| Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative forward commitments, 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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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 portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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