Note 3 - Loans Held for Investment, Net (Details Textual)	6 Months Ended
Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Loans Receivable, Gross, Commercial, Construction	$ 20,300,000		$ 16,400,000
Financing Receivable, Recorded Investment, Nonaccrual Status	5,585,526		5,436,972
Impaired Financing Receivable, Interest Income, Accrual Method, Total	4,000	$ 0
Financing Receivable, Modifications, Recorded Investment	$ 0		$ 0
Veterans Administration Loan [Member]
Number of Receivable Commitments Outstanding	0		0
Real Estate [Member]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 4,500,000
Nonaccrual Loan Secure Percentage	80.00%
Small Business Administration [Member]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 3,600,000
Nonaccrual Loan Secure Percentage	64.20%
Commercial Real Estate Portfolio Segment [Member]
Loans Receivable, Gross, Commercial, Construction	$ 16,700,000		$ 13,400,000
Financing Receivable, Recorded Investment, Nonaccrual Status	3,621,812		3,483,078
One-to-four Family Residential Real Estate Portfolio Segment [Member]
Loans Receivable, Gross, Commercial, Construction	1,900,000		1,300,000
Financing Receivable, Recorded Investment, Nonaccrual Status	689,004		679,184
Consumer Portfolio Segment [Member]
Loans and Leases Receivable, Gross, Consumer, Construction	$ 1,700,000		$ 1,700,000

It represents the percentage of nonaccrual loans secured.

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- Definition

The number of receivable commitments outstanding.

+ References

No definition available.

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 7
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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-Publisher FASB
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- Definition

Amount before allowance of loans issued to build, improve or remodel a residential home. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount before allowance of commercial construction loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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