Note 7 - Fair Values of Financial Instruments - Assets at Fair Value (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Available-for-sale Securities, fair value disclosure	$ 32,570,879	$ 33,428,658
Assets, fair value disclosure	51,057,001	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	47,090,536	60,158,766
Fair Value, Inputs, Level 3 [Member]
Assets, fair value disclosure	3,966,465	4,024,474
Fair Value, Recurring [Member]
Loans held for sale, fair value disclosure	14,614,579
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Loans held for sale, fair value disclosure	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Loans held for sale, fair value disclosure	14,614,579
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans held for sale, fair value disclosure	0
Fair Value, Nonrecurring [Member]
Loans held for sale, fair value disclosure		26,884,014
Impaired loans, fair value disclosure	3,605,635	3,643,608
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Loans held for sale, fair value disclosure		0
Impaired loans, fair value disclosure		0
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Loans held for sale, fair value disclosure		26,884,014
Impaired loans, fair value disclosure		0
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Loans held for sale, fair value disclosure		0
Impaired loans, fair value disclosure	3,605,635	3,643,608
Asset-backed Securities [Member]
Available-for-sale Securities, fair value disclosure	27,543,018	28,310,358
Asset-backed Securities [Member] \| Fair Value, Recurring [Member]
Available-for-sale Securities, fair value disclosure	27,543,018	28,310,358
Asset-backed Securities [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Available-for-sale Securities, fair value disclosure	0	0
Asset-backed Securities [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale Securities, fair value disclosure	27,543,018	28,310,358
Asset-backed Securities [Member] \| Fair Value, 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	1,310,423	1,445,032
US Government Agencies Debt Securities [Member] \| Fair Value, Recurring [Member]
Available-for-sale Securities, fair value disclosure	1,310,423	1,445,032
US Government Agencies Debt Securities [Member] \| Fair Value, 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, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale Securities, fair value disclosure	1,310,423	1,445,032
US Government Agencies Debt Securities [Member] \| Fair Value, 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	3,717,438	3,673,268
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Recurring [Member]
Available-for-sale Securities, fair value disclosure	3,717,438	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, fair value disclosure	0	0
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Available-for-sale Securities, fair value disclosure	3,717,438	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, fair value disclosure	0	0
Interest Rate Lock Commitments [Member] \| Fair Value, Recurring [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLC's, fair value disclosure	360,830	380,866
Interest Rate Lock Commitments [Member] \| Fair Value, 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, 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, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative IRLC's, fair value disclosure	360,830	380,866
Forward Contracts [Member] \| Fair Value, Recurring [Member] \| Not Designated as Hedging Instrument [Member]
Derivative forward commitments, fair value disclosure	(94,922)	(153,906)
Forward Contracts [Member] \| Fair Value, 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, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Derivative forward commitments, fair value disclosure	(94,922)	(153,906)
Forward Contracts [Member] \| Fair Value, 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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