Federal Home Loan Bank and Short-term Borrowings (Detail)	12 Months Ended
Dec. 31, 2017 USD ($) item shares	Dec. 31, 2016 USD ($)
Short-term Debt [Line Items]
Federal home loan bank shares owned \| shares	12,023
Percentage of investment to be maintained on total assets	0.09%
Amount of dollar cap on total assets	$ 15,000,000
Additional percentage of investment to be maintained on total advances	4.25%
Percentage of credit available on total assets	25.00%
Amount of credit available on total assets	$ 97,500,000
Short term advances	20,000,000
Average short-term borrowings	$ 1,468,767	$ 137
Number of financial institution lending credit facility \| item	2
Line of credit outstanding	$ 0
Convertible advances maturing on November, 1, 2018 \| Federal Home Loan Bank of Atlanta [Member]
Short-term Debt [Line Items]
Convertible debt	$ 10,000,000
Debt instrument, maturity date	Nov. 01, 2018
Debt instrument, interest rate, stated percentage	1.38%
Convertible advances maturing on July 23, 2018 \| Federal Home Loan Bank of Atlanta [Member]
Short-term Debt [Line Items]
Convertible debt	$ 5,000,000
Debt instrument, maturity date	Jul. 23, 2018
Debt instrument, interest rate, stated percentage	2.73%
Convertible advances maturing on August 22, 2018 \| Federal Home Loan Bank of Atlanta [Member]
Short-term Debt [Line Items]
Convertible debt	$ 5,000,000
Debt instrument, maturity date	Aug. 22, 2018
Debt instrument, interest rate, stated percentage	3.34%
Financial Bank One [Member]
Short-term Debt [Line Items]
Line of credit, amount available for borrowing	$ 5,000,000
Financial Bank Two [Member]
Short-term Debt [Line Items]
Line of credit, amount available for borrowing	$ 6,000,000

Additional Percentage Of Investment To Be Maintained On Total Advances.

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Amount Of Credit Available On Total Assets.

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Dollar cap on total assets.

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Federal Home Loan Bank Shares Owned.

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Represents the number of financial institutions lending credit facility.

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Percentage Of Credit Available On Total Assets.

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Percentage Of Investment To Be Maintained On Total Assets.

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Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, average borrowings during the period.

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