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Fair Values of Financial Instruments - Carrying Amount, Estimated Fair Value and Level Within Fair Value Hierarchy of Financial Instruments (Detail) (USD $) | Dec. 31, 2013 | Dec. 31, 2012
--- | --- | ---
Financial assets |  |
Securities available for sale | $ 131,178,000 | $ 138,314,000
Carrying Amount [Member] |  |
Financial assets |  |
Securities available for sale | 131,178,000 | 138,314,000
Federal Home Loan Bank stock | 11,961,000 | 11,961,000
Carrying Amount [Member] | Level 1 [Member] |  |
Financial assets |  |
Cash | 1,464,000 | 1,576,000
Carrying Amount [Member] | Level 2 [Member] |  |
Financial assets |  |
Cash equivalents | 145,501,000 | 134,427,000
Bank owned life insurance | 51,377,000 | 50,048,000
Accrued interest receivable | 3,649,000 | 3,874,000
Financial liabilities |  |
Deposits | 1,118,911,000 | 1,135,204,000
Securities sold under agreements to repurchase | 69,305,000 | 64,765,000
Federal Home Loan Bank advances | 45,000,000 | 35,000,000
Subordinated debentures | 32,990,000 | 32,990,000
Accrued interest payable | 2,041,000 | 2,314,000
Carrying Amount [Member] | Level 3 [Member] |  |
Financial assets |  |
Loans, net | 1,030,422,000 | 1,012,512,000
Carrying Amount [Member] | Interest rate swap agreement [Member] |  |
Financial liabilities |  |
Interest rate swap | 264,000 | 1,113,000
Fair Value [Member] |  |
Financial assets |  |
Securities available for sale | 131,178,000 | 138,314,000
Federal Home Loan Bank stock | 11,961,000 | 11,961,000
Fair Value [Member] | Level 1 [Member] |  |
Financial assets |  |
Cash | 1,464,000 | 1,576,000
Fair Value [Member] | Level 2 [Member] |  |
Financial assets |  |
Cash equivalents | 145,501,000 | 134,427,000
Bank owned life insurance | 51,377,000 | 50,048,000
Accrued interest receivable | 3,649,000 | 3,874,000
Financial liabilities |  |
Deposits | 1,120,576,000 | 1,135,614,000
Securities sold under agreements to repurchase | 69,305,000 | 64,765,000
Federal Home Loan Bank advances | 45,139,000 | 35,000,000
Subordinated debentures | 32,974,000 | 32,943,000
Accrued interest payable | 2,041,000 | 2,314,000
Fair Value [Member] | Level 3 [Member] |  |
Financial assets |  |
Loans, net | 1,027,300,000 | 1,004,541,000
Fair Value [Member] | Interest rate swap agreement [Member] |  |
Financial liabilities |  |
Interest rate swap | $ 264,000 | $ 1,113,000

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