Note 6 - Fair Values of Financial Instruments - Fair Value of Assets (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Available-for-sale Securities, fair value disclosure	$ 26,715,509	$ 31,499,132
Assets, Fair Value Disclosure	43,253,692	51,688,516
Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument [Member]
Derivative assets (IRLC's), fair value disclosure	235,000
Forward Contracts [Member] \| Not Designated as Hedging Instrument [Member] \| Commercial Mortgage Backed Securities [Member]
Derivative assets (MBS forward trades), fair value disclosure	21,000
Fair Value, Inputs, Level 1 [Member]
Assets, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure	37,215,665	45,720,295
Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure	6,038,027	5,968,221
Fair Value, Measurements, Recurring [Member] \| Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument [Member]
Derivative assets (IRLC's), fair value disclosure	235,401
Fair Value, Measurements, Recurring [Member] \| Forward Contracts [Member] \| Not Designated as Hedging Instrument [Member] \| Commercial Mortgage Backed Securities [Member]
Derivative assets (MBS forward trades), fair value disclosure	21,016
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument [Member]
Derivative assets (IRLC's), fair value disclosure	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Forward Contracts [Member] \| Not Designated as Hedging Instrument [Member] \| Commercial Mortgage Backed Securities [Member]
Derivative assets (MBS forward trades), fair value disclosure	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument [Member]
Derivative assets (IRLC's), fair value disclosure	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Forward Contracts [Member] \| Not Designated as Hedging Instrument [Member] \| Commercial Mortgage Backed Securities [Member]
Derivative assets (MBS forward trades), fair value disclosure	21,016
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Interest Rate Lock Commitments [Member] \| Not Designated as Hedging Instrument [Member]
Derivative assets (IRLC's), fair value disclosure	235,401
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Forward Contracts [Member] \| Not Designated as Hedging Instrument [Member] \| Commercial Mortgage Backed Securities [Member]
Derivative assets (MBS forward trades), fair value disclosure	0
Fair Value, Measurements, Nonrecurring [Member]
Loans held-for-sale, fair value disclosure	10,479,140	14,221,163
Impaired loans, fair value disclosure	5,802,626	5,968,221
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	10,479,140	14,221,163
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	0
Impaired loans, fair value disclosure	5,802,626	5,968,221
Collateralized Mortgage Backed Securities [Member]
Available-for-sale Securities, fair value disclosure	22,994,426	27,128,397
Collateralized Mortgage Backed Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Available-for-sale Securities, fair value disclosure	22,994,426	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	22,994,426	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	2,031,252	2,525,736
US Government Agencies Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Available-for-sale Securities, fair value disclosure	2,031,252	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	2,031,252	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	1,689,831	1,844,999
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Measurements, Recurring [Member]
Available-for-sale Securities, fair value disclosure	168,983	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	1,689,831	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, 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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