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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 $) | Sep. 30, 2013 | Dec. 31, 2012
--- | --- | ---
Financial assets: |  |
Securities available for sale | $ 123,793,000 | $ 138,314,000
Carrying Values [Member] |  |
Financial assets: |  |
Securities available for sale | 123,793,000 | 138,314,000
FHLB stock | 11,961,000 | 11,961,000
Carrying Values [Member] | Level 1 [Member] |  |
Financial assets: |  |
Cash | 1,995,000 | 1,576,000
Carrying Values [Member] | Level 2 [Member] |  |
Financial assets: |  |
Cash equivalents | 123,923,000 | 134,427,000
Bank owned life insurance | 51,073,000 | 50,048,000
Accrued interest receivable | 3,777,000 | 3,874,000
Financial liabilities: |  |
Deposits | 1,121,509,000 | 1,135,204,000
Repurchase agreements | 65,680,000 | 64,765,000
FHLB advances | 45,000,000 | 35,000,000
Subordinated debentures | 32,990,000 | 32,990,000
Accrued interest payable | 1,643,000 | 2,314,000
Carrying Values [Member] | Level 3 [Member] |  |
Financial assets: |  |
Loans, net | 1,050,292,000 | 1,012,512,000
Carrying Values [Member] | Interest rate swap agreement [Member] |  |
Financial liabilities: |  |
Interest rate swap | 394,000 | 1,113,000
Fair Values [Member] |  |
Financial assets: |  |
Securities available for sale | 123,793,000 | 138,314,000
FHLB stock | 11,961,000 | 11,961,000
Fair Values [Member] | Level 1 [Member] |  |
Financial assets: |  |
Cash | 1,995,000 | 1,576,000
Fair Values [Member] | Level 2 [Member] |  |
Financial assets: |  |
Cash equivalents | 123,923,000 | 134,427,000
Bank owned life insurance | 51,073,000 | 50,048,000
Accrued interest receivable | 3,777,000 | 3,874,000
Financial liabilities: |  |
Deposits | 1,123,304,000 | 1,135,614,000
Repurchase agreements | 65,680,000 | 64,765,000
FHLB advances | 45,139,000 | 35,000,000
Subordinated debentures | 32,974,000 | 32,943,000
Accrued interest payable | 1,643,000 | 2,314,000
Fair Values [Member] | Level 3 [Member] |  |
Financial assets: |  |
Loans, net | 1,047,313,000 | 1,004,541,000
Fair Values [Member] | Interest rate swap agreement [Member] |  |
Financial liabilities: |  |
Interest rate swap | $ 394,000 | $ 1,113,000

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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562 + Details
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- Definition Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Surrender Value -URI http://asc.fasb.org/extlink&oid=6507153 + Details
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- Definition Fair value portion of borrowing from Federal Home Loan Bank (FHLBank). + 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 210.9-03.13(3)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 325 -SubTopic 20 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=29638263&loc=d3e39828-111592 + Details
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- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Glossary Loan -URI http://asc.fasb.org/extlink&oid=6517073 + Details
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