Loans - Allowance for Loan Losses (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Allowance for loan losses:
Allowance for loan losses, beginning of period	$ 25,596	$ 26,934
Provision for loan losses	13,075	20,500	47,100
Loan charge-offs	22,520	22,832
Loan recoveries	1,674	994
Net loans charged-off	20,846	21,838
Allowance for loan losses, end of period	17,825	25,596	26,934
Individually evaluated for impairment	2,477	6,505
Collectively evaluated for impairment	15,348	19,091
Loans, gross, end of period:
Total loans, gross	738,282	773,558
Loans Receivable [Member]
Allowance for loan losses:
Allowance for loan losses, end of period	17,825	25,596
Loans, gross, end of period:
Individually evaluated for impairment	41,319	69,791
Collectively evaluated for impairment	696,963	703,767
Commercial real estate [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	18,026	18,979
Provision for loan losses	11,630	15,478
Loan charge-offs	17,548	16,532
Loan recoveries	209	101
Net loans charged-off	17,339	16,431
Allowance for loan losses, end of period	12,317	18,026
Individually evaluated for impairment	2,199	6,196
Collectively evaluated for impairment	10,118	11,830
Loans, gross, end of period:
Total loans, gross	458,436	478,576
Commercial real estate [Member] \| Loans Receivable [Member]
Allowance for loan losses:
Allowance for loan losses, end of period	12,317	18,026
Loans, gross, end of period:
Individually evaluated for impairment	36,553	63,625
Collectively evaluated for impairment	421,883	414,951
Single-family residential loans [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	4,488	4,061
Provision for loan losses	1,318	3,441
Loan charge-offs	3,314	3,070
Loan recoveries	648	56
Net loans charged-off	2,666	3,014
Allowance for loan losses, end of period	3,140	4,488
Individually evaluated for impairment	216	215
Collectively evaluated for impairment	2,924	4,273
Loans, gross, end of period:
Total loans, gross	168,180	185,504
Single-family residential loans [Member] \| Loans Receivable [Member]
Allowance for loan losses:
Allowance for loan losses, end of period	3,140	4,488
Loans, gross, end of period:
Individually evaluated for impairment	3,278	4,614
Collectively evaluated for impairment	164,902	180,890
Commercial and Industrial [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	1,862	2,492
Provision for loan losses	(390)	827
Loan charge-offs	376	1,572
Loan recoveries	168	115
Net loans charged-off	208	1,457
Allowance for loan losses, end of period	1,264	1,862
Individually evaluated for impairment	58	88
Collectively evaluated for impairment	1,206	1,774
Loans, gross, end of period:
Total loans, gross	51,661	49,381
Commercial and Industrial [Member] \| Loans Receivable [Member]
Allowance for loan losses:
Allowance for loan losses, end of period	1,264	1,862
Loans, gross, end of period:
Individually evaluated for impairment	1,450	1,508
Collectively evaluated for impairment	50,211	47,873
Consumer [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	1,209	1,375
Provision for loan losses	277	498
Loan charge-offs	586	810
Loan recoveries	193	146
Net loans charged-off	393	664
Allowance for loan losses, end of period	1,093	1,209
Individually evaluated for impairment	4	6
Collectively evaluated for impairment	1,089	1,203
Loans, gross, end of period:
Total loans, gross	50,574	52,771
Consumer [Member] \| Loans Receivable [Member]
Allowance for loan losses:
Allowance for loan losses, end of period	1,093	1,209
Loans, gross, end of period:
Individually evaluated for impairment	38	44
Collectively evaluated for impairment	50,536	52,727
Other [Member]
Allowance for loan losses:
Allowance for loan losses, beginning of period	11	27
Provision for loan losses	240	256
Loan charge-offs	696	848
Loan recoveries	456	576
Net loans charged-off	240	272
Allowance for loan losses, end of period	11	11
Collectively evaluated for impairment	11	11
Loans, gross, end of period:
Total loans, gross	9,431	7,326
Other [Member] \| Loans Receivable [Member]
Allowance for loan losses:
Allowance for loan losses, end of period	11	11
Loans, gross, end of period:
Collectively evaluated for impairment	$ 9,431	$ 7,326

Allowance for loan and lease losses write offs net of recoveries.

No definition available.

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- Definition

Reflects a reduction in bad debt expense attributable to collections of loans and lease receivables which had previously been fully or partially charged off as bad debts.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 114

-Paragraph 20

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- Definition

Reflects the amount of loans and leases that have been removed, or charged off, from both loan receivables and the reserve for credit losses, typically because they are considered to be not salvageable or have been purchased by unconsolidated collection entities.

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 5

-Paragraph 8, 9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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-Name Statement of Position (SOP)

-Number 01-6

-Paragraph 13

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- Definition

Provision charged for the period based on estimated losses to be realized from loan and lease transactions.

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-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 168, 169, 170

-IssueDate 2006-05-01

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