Other Borrowings - Additional Information (Detail) (USD $)	6 Months Ended
Jun. 30, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Unused lines of credit	$ 106,500,000	$ 105,400,000
Blanket floating lien agreement	19.00%
Borrowings of Bank	6,000,000	6,000,000
Borrowings of Bank, maturity date	Dec. 28, 2018
Weighted average rate	1.91%
Collateral pledged on borrowings including real estate loans	89,900,000	100,000,000
Book value of FHLB stock	909,000	1,078,000
Note payable monthly payments	2,000
Minimum [Member]
Debt Instrument [Line Items]
Interest rate	1.78%
Maximum [Member]
Debt Instrument [Line Items]
Interest rate	2.04%
Notes Payable to Banks [Member]
Debt Instrument [Line Items]
Borrowings of Bank	64,000	76,000
Borrowings of Bank, maturity date	Jan. 03, 2016
Fixed interest rate	4.00%
Letter of Credit [Member]
Debt Instrument [Line Items]
Borrowings of Bank	30,000,000	30,000,000
FHLB [Member]
Debt Instrument [Line Items]
Unused lines of credit	$ 30,000,000

Collateral pledged borrowing.

No definition available.

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- Definition

Note payable monthly payments.

+ References

No definition available.

+ Details

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- Definition

Percentage of assets for maximum borrowing.

+ References

No definition available.

+ Details

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- Definition

Reflects the effective interest rate as of the balance sheet date on interest-bearing trade payables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 25

-Paragraph 13

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- Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.22(a)(2))

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

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-Publisher FASB

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Section 03

-Paragraph 13, 16

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- Definition

The average discount rate applied to insurance contracts to determine future policy benefits to be paid to or on behalf of policyholders.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 40

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-Subparagraph (b)

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