Fair Value of Financial Instruments - Estimated Fair Values and Related Carrying or Notional Amounts (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Financial Assets:
Cash and Cash Equivalents	$ 25,908	$ 22,018	$ 45,101	$ 24,295
Interest-bearing time deposits	1,960
Securities - available-for-sale	226,512	235,115
Other Securities	3,717	3,717
Loans, net	701,375	679,821
Financial Liabilities:
Non-interest bearing Deposits	163,769	171,112
Time Deposits	184,722	184,285
Total deposits	798,132	771,339
Fed Funds purchased and Securities sold under agreement to repurchase	69,390	78,815
Federal Home Loan Bank advances	10,000	10,000
Carrying Amount [Member]
Financial Assets:
Cash and Cash Equivalents	25,908	22,018
Interest-bearing time deposits	1,960
Securities - available-for-sale	226,512	235,115
Other Securities	3,717	3,717
Loans, net	701,375	679,821
Interest receivable	4,112	3,589
Financial Liabilities:
Interest bearing Deposits	449,641	415,942
Non-interest bearing Deposits	163,769	171,112
Time Deposits	184,722	184,285
Total deposits	798,132	771,339
Fed Funds purchased and Securities sold under agreement to repurchase	69,390	78,815
Federal Home Loan Bank advances	10,000	10,000
Interest payable	222	185
Fair Value [Member]
Financial Assets:
Cash and Cash Equivalents	25,908	22,018
Interest-bearing time deposits	1,960
Securities - available-for-sale	226,512	235,115
Other Securities	3,717	3,717
Loans, net	704,996	683,332
Interest receivable	4,112	3,589
Financial Liabilities:
Interest bearing Deposits	449,641	415,942
Non-interest bearing Deposits	163,769	171,112
Time Deposits	184,843	184,308
Total deposits	798,253	771,362
Fed Funds purchased and Securities sold under agreement to repurchase	69,390	78,815
Federal Home Loan Bank advances	9,822	9,986
Interest payable	222	185
Level 1 [Member]
Financial Assets:
Cash and Cash Equivalents	25,908	22,018
Securities - available-for-sale	33,721	38,505
Level 2 [Member]
Financial Assets:
Interest-bearing time deposits	1,960
Securities - available-for-sale	185,676	189,258
Financial Liabilities:
Non-interest bearing Deposits	163,769	171,112
Total deposits	163,769	171,112
Level 3 [Member]
Financial Assets:
Securities - available-for-sale	7,115	7,352
Other Securities	3,717	3,717
Loans, net	704,996	683,332
Interest receivable	4,112	3,589
Financial Liabilities:
Interest bearing Deposits	449,641	415,942
Time Deposits	184,843	184,308
Total deposits	634,484	600,250
Fed Funds purchased and Securities sold under agreement to repurchase	69,390	78,815
Federal Home Loan Bank advances	9,822	9,986
Interest payable	$ 222	$ 185

Accrued interest payable.

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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The sum of cash and cash equivalents plus Federal Funds Sold. Cash and cash equivalents consist of short term, highly liquid investments that are readily convertible to known amounts of cash and are so near their maturity that they present negligible risk of changes in value due to changes in interest rates -- usually with an original maturity less than 90 days.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Amount after offset of short term borrowing where a bank borrows, at the federal funds rate, from another bank and securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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The aggregate of all domestic and foreign interest-bearing deposit liabilities.

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

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Includes other investments and securities that are not at fair value as of the balance sheet date and those that are not accounted for under the equity method.

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Amount of deposits that cannot be withdrawn before a set date without penalty or for which notice of withdrawal is required. Time deposits include, but are not limited to, certificates of deposits, individual retirement accounts and open accounts.

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