Loans - Activity In ALLL By Portfolio Segment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	$ 5,434	$ 8,050	$ 6,110	$ 9,758
Addition to (reduction in) provision for loan losses	543	405	943	2,256
Charge-offs	(536)	(1,596)	(2,101)	(5,368)
Recoveries	10	94	490	308
Reclass of ALLL on loan-related commitments	(9)	2		1
Ending balance	5,442	6,955	5,442	6,955
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	1,386	2,754	2,281	1,879
Addition to (reduction in) provision for loan losses	(370)	(266)	(1,467)	1,679
Charge-offs			(99)	(1,140)
Recoveries		29	292	100
Reclass of ALLL on loan-related commitments	(9)	2		1
Ending balance	1,007	2,519	1,007	2,519
Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance				74
Addition to (reduction in) provision for loan losses				(74)
Real Estate [Member] \| Single-family residential [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	245	242	207	241
Addition to (reduction in) provision for loan losses	(15)	(54)	23	(43)
Charge-offs			(7)	(14)
Recoveries	1	2	8	6
Ending balance	231	190	231	190
Real Estate [Member] \| Multi-family residential [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	1,370	2,183	1,470	2,520
Addition to (reduction in) provision for loan losses	544	1,015	856	1,926
Charge-offs		(867)	(434)	(2,117)
Recoveries			22	2
Ending balance	1,914	2,331	1,914	2,331
Real Estate [Member] \| Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	2,130	2,632	1,863	4,719
Addition to (reduction in) provision for loan losses	510	(387)	1,570	(1,247)
Charge-offs	(536)	(580)	(1,467)	(1,930)
Recoveries		47	138	170
Ending balance	2,104	1,712	2,104	1,712
Consumer [Member] \| Home equity lines of credit [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	286	220	272	303
Addition to (reduction in) provision for loan losses	(115)	100	(51)	12
Charge-offs		(149)	(60)	(149)
Recoveries	3	15	13	20
Ending balance	174	186	174	186
Consumer [Member] \| Other [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	17	19	17	22
Addition to (reduction in) provision for loan losses	(11)	(3)	12	3
Charge-offs			(34)	(18)
Recoveries	6	1	17	10
Ending balance	$ 12	$ 17	$ 12	$ 17

Reflects the gross amount charged against earnings during the period as credit losses (bad debt expense) based on review of the loan and lease portfolio and application of the methodology for estimating credit losses.

+ References+ Details

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.

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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

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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (b)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Section 563c.102

-Paragraph 8

-Subparagraph a(ii)

-Chapter V

-Subsection I

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph d

-Article 9

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 114

-Paragraph 20

-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.

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section L

-Subsection 1

+ Details