Summary of Estimated Fair Values of Financial Instruments (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Carrying (Reported) Amount, Fair Value Disclosure
Financial assets:
Investment securities	$ 102,510	$ 102,867
Investments in restricted stock	1,718	1,520
Ground rents	175	175
Loans, net	249,353	232,734
Accrued interest receivable	1,558	1,542
Financial liabilities:
Deposits	321,798	311,945
Short-term borrowings	3,000	255
Long-term borrowings	20,000	20,000
Dividends payable	273	272
Accrued interest payable	54	48
Off-balance sheet commitments	26,176	22,736
Carrying (Reported) Amount, Fair Value Disclosure \| Cash and due from banks
Financial assets:
Cash and cash equivalents	7,059	6,877
Carrying (Reported) Amount, Fair Value Disclosure \| Interest-bearing deposits
Financial assets:
Cash and cash equivalents	166	2,423
Carrying (Reported) Amount, Fair Value Disclosure \| Federal funds sold
Financial assets:
Cash and cash equivalents	258	654
Estimate of Fair Value, Fair Value Disclosure
Financial assets:
Investment securities	102,510	102,867
Investments in restricted stock	1,718	1,520
Ground rents	175	175
Loans, net	251,387	231,912
Accrued interest receivable	1,558	1,542
Financial liabilities:
Deposits	305,402	293,713
Short-term borrowings	3,000	255
Long-term borrowings	21,737	21,425
Dividends payable	273	272
Accrued interest payable	54	48
Off-balance sheet commitments	26,176	22,736
Estimate of Fair Value, Fair Value Disclosure \| Cash and due from banks
Financial assets:
Cash and cash equivalents	7,059	6,877
Estimate of Fair Value, Fair Value Disclosure \| Interest-bearing deposits
Financial assets:
Cash and cash equivalents	166	2,423
Estimate of Fair Value, Fair Value Disclosure \| Federal funds sold
Financial assets:
Cash and cash equivalents	$ 258	$ 654

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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