Note 20 - Fair Values of Financial Instruments - Assets at Fair Value (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Available-for-sale securities, at fair value	$ 44,517,178	$ 33,428,658
Assets, fair value disclosure	48,022,466	64,183,240
Fair Value, Inputs, Level 1 [Member]
Assets, fair value disclosure	0	0
Fair Value, Inputs, Level 2 [Member]
Assets, fair value disclosure	44,517,178	60,158,766
Fair Value, Inputs, Level 3 [Member]
Assets, fair value disclosure	3,505,288	4,024,474
Fair Value, Recurring [Member]
Loans held for sale		26,884,014
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Loans held for sale		0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Loans held for sale		26,884,014
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans held for sale		0
Fair Value, Nonrecurring [Member]
Impaired loans, fair value disclosure	3,505,288	3,643,608
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Impaired loans, fair value disclosure		0
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Impaired loans, fair value disclosure		0
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Impaired loans, fair value disclosure	3,505,288	3,643,608
Asset-backed Securities [Member]
Available-for-sale securities, at fair value	31,018,748	28,310,358
Asset-backed Securities [Member] \| Fair Value, Recurring [Member]
Available-for-sale securities, at fair value	31,018,748	28,310,358
Asset-backed Securities [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale securities, at fair value	0	0
Asset-backed Securities [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities, at fair value	31,018,748	28,310,358
Asset-backed Securities [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale securities, at fair value	0	0
US Government Agencies Debt Securities [Member]
Available-for-sale securities, at fair value	1,079,447	1,445,032
US Government Agencies Debt Securities [Member] \| Fair Value, Recurring [Member]
Available-for-sale securities, at fair value	1,079,447	1,445,032
US Government Agencies Debt Securities [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale securities, at fair value	0	0
US Government Agencies Debt Securities [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities, at fair value	1,079,447	1,445,032
US Government Agencies Debt Securities [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale securities, at fair value	0	0
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, at fair value	12,418,983	3,673,268
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Recurring [Member]
Available-for-sale securities, at fair value	12,418,983	3,673,268
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale securities, at fair value	0	0
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities, at fair value	12,418,983	3,673,268
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Available-for-sale securities, at fair value	0	0
Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument [Member]
Derivative forward commitments	0	381,000
Interest Rate Lock Commitments [Member] \| Fair Value, Recurring [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLCs, fair value disclosure		380,866
Interest Rate Lock Commitments [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLCs, fair value disclosure
Interest Rate Lock Commitments [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLCs, fair value disclosure
Interest Rate Lock Commitments [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLCs, fair value disclosure		380,866
Forward Contracts [Member] \| Not Designated as Hedging Instrument [Member]
Derivative forward commitments	$ 0	154,000
Forward Contracts [Member] \| Fair Value, Recurring [Member] \| Not Designated as Hedging Instrument [Member]
Derivative forward commitments		(153,906)
Forward Contracts [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative forward commitments		0
Forward Contracts [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative forward commitments		(153,906)
Forward Contracts [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative forward commitments		$ 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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