Impaired Loans (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Financing Receivable, Impaired [Line Items]
Recorded Investment	$ 3,669	$ 3,791
Unpaid Principal Balance	4,273	4,120
Average Recorded Investment	3,731	4,194
Interest Income Recognized	28	14
Interest Recognized-Cash Method	30	6
Recorded Investment	2,918	3,129
Unpaid Principal Balance	3,255	3,466
Related Allowance	1,460	1,529
Average Recorded Investment	3,024	3,926
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Recorded Investment	6,587	6,920
Unpaid Principal Balance	7,528	7,586
Related Allowance	1,460	1,529
Average Recorded Investment	6,755	8,120
Interest Income Recognized	28	14
Interest Recognized-Cash Method	30	6
Residential
Financing Receivable, Impaired [Line Items]
Recorded Investment	1,373	1,591
Unpaid Principal Balance	1,671	1,869
Average Recorded Investment	1,482	1,594
Interest Income Recognized	10	4
Interest Recognized-Cash Method	13	3
Recorded Investment	265	449
Unpaid Principal Balance	293	487
Related Allowance	70	112
Average Recorded Investment	357	776
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Recorded Investment	1,638	2,040
Unpaid Principal Balance	1,964	2,356
Related Allowance	70	112
Average Recorded Investment	1,839	2,370
Interest Income Recognized	10	4
Interest Recognized-Cash Method	13	3
Land
Financing Receivable, Impaired [Line Items]
Recorded Investment	118	120
Unpaid Principal Balance	132	131
Average Recorded Investment	119	125
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
Average Recorded Investment	0	3
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Recorded Investment	118	120
Unpaid Principal Balance	132	131
Related Allowance	0	0
Average Recorded Investment	119	128
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Construction
Financing Receivable, Impaired [Line Items]
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Average Recorded Investment	0	332
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
Average Recorded Investment	0	332
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Recorded Investment	1,792	1,637
Unpaid Principal Balance	2,053	1,643
Average Recorded Investment	1,715	2,022
Interest Income Recognized	17	9
Interest Recognized-Cash Method	17	3
Recorded Investment	931	949
Unpaid Principal Balance	1,040	1,048
Related Allowance	127	145
Average Recorded Investment	940	1,318
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Recorded Investment	2,723	2,586
Unpaid Principal Balance	3,093	2,691
Related Allowance	127	145
Average Recorded Investment	2,655	3,340
Interest Income Recognized	17	9
Interest Recognized-Cash Method	17	3
Commercial Business
Financing Receivable, Impaired [Line Items]
Recorded Investment	189	189
Unpaid Principal Balance	209	209
Average Recorded Investment	189	0
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Recorded Investment	1,709	1,709
Unpaid Principal Balance	1,909	1,909
Related Allowance	1,259	1,259
Average Recorded Investment	1,709	1,776
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Recorded Investment	1,898	1,898
Unpaid Principal Balance	2,118	2,118
Related Allowance	1,259	1,259
Average Recorded Investment	1,898	1,776
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Home Equity and Second Mortgage
Financing Receivable, Impaired [Line Items]
Recorded Investment	197	254
Unpaid Principal Balance	208	268
Average Recorded Investment	226	121
Interest Income Recognized	1	1
Interest Recognized-Cash Method	0	0
Recorded Investment	13	22
Unpaid Principal Balance	13	22
Related Allowance	4	13
Average Recorded Investment	18	53
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Recorded Investment	210	276
Unpaid Principal Balance	221	290
Related Allowance	4	13
Average Recorded Investment	244	174
Interest Income Recognized	1	1
Interest Recognized-Cash Method	0	0
Other Consumer
Financing Receivable, Impaired [Line Items]
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Interest Recognized-Cash Method	0	0
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Related Allowance	0	0
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Interest Recognized-Cash Method	$ 0	$ 0

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5212-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5258-111524

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+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953550-111524

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