Note 7 - Fair Values of Financial Instruments - Assets at Fair Value (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Available-for-sale Securities, fair value disclosure	$ 27,930,267	$ 24,399,881
Assets, fair value disclosure	53,874,163	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	48,193,645	39,807,731
Fair Value, Inputs, Level 3 [Member]
Assets, fair value disclosure	5,680,518	5,620,059
Fair Value, Measurements, Recurring [Member]
Loans held for sale, fair value disclosure	20,219,237
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Loans held for sale, fair value disclosure	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Loans held for sale, fair value disclosure	20,219,237
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	5,344,477	5,436,972
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Loans held for sale, fair value disclosure		0
Impaired loans, fair value disclosure		0
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Loans held for sale, fair value disclosure		15,423,670
Impaired loans, fair value disclosure		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	5,344,477	5,436,972
Asset-backed Securities [Member]
Available-for-sale Securities, fair value disclosure	23,360,230	20,768,592
Asset-backed Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Available-for-sale Securities, fair value disclosure	23,360,230	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	23,360,230	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	1,507,514	1,957,783
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Available-for-sale Securities, fair value disclosure	1,507,514	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	1,507,514	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	3,062,523	1,673,506
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Available-for-sale Securities, fair value disclosure	3,062,523	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	3,062,523	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 IRLC's, fair value disclosure	336,041	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 IRLC's, 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 IRLC's, 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 IRLC's, fair value disclosure	336,041	183,087
Forward Contracts [Member] \| Fair Value, Measurements, Recurring [Member] \| Not Designated as Hedging Instrument [Member]
Derivative forward commitments, fair value disclosure	44,141	(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	44,141	(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 portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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