Impaired Loans (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Financing Receivable, Impaired [Line Items]
Recorded Investment	$ 3,341		$ 3,341		$ 3,791
Unpaid Principal Balance	3,691		3,691		4,120
Average Recorded Investment	3,382	1,988	3,518	2,487
Interest Income Recognized	25	7	53	11
Interest Recognized-Cash Method	28	4	58	5
Recorded Investment	2,849		2,849		3,129
Unpaid Principal Balance	3,242		3,242		3,466
Related Allowance	1,394		1,394		1,529
Average Recorded Investment	3,304	3,614	3,245	3,774
Interest Income Recognized	0	0	0	1
Interest Recognized-Cash Method	0	0	0	0
Recorded Investment	6,190		6,190		6,920
Unpaid Principal Balance	6,933		6,933		7,586
Related Allowance	1,394		1,394		1,529
Average Recorded Investment	6,686	5,602	6,763	6,261
Interest Income Recognized	25	7	53	12
Interest Recognized-Cash Method	28	4	58	5
Residential
Financing Receivable, Impaired [Line Items]
Recorded Investment	1,184		1,184		1,591
Unpaid Principal Balance	1,462		1,462		1,869
Average Recorded Investment	1,345	1,273	1,427	1,324
Interest Income Recognized	8	2	18	5
Interest Recognized-Cash Method	9	0	21	1
Recorded Investment	262		262		449
Unpaid Principal Balance	302		302		487
Related Allowance	61		61		112
Average Recorded Investment	436	625	440	731
Interest Income Recognized	0	0	0	0
Interest Recognized-Cash Method	0	0	0	0
Recorded Investment	1,446		1,446		2,040
Unpaid Principal Balance	1,764		1,764		2,356
Related Allowance	61		61		112
Average Recorded Investment	1,781	1,898	1,867	2,055
Interest Income Recognized	8	2	18	5
Interest Recognized-Cash Method	9	0	21	1
Land
Financing Receivable, Impaired [Line Items]
Recorded Investment	113		113		120
Unpaid Principal Balance	129		129		131
Average Recorded Investment	119	126	119	125
Interest Income Recognized	0	0	0	0
Interest Recognized-Cash Method	0	0	0	0
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	3	3	2	2
Interest Income Recognized	0	0	0	0
Interest Recognized-Cash Method	0	0	0	0
Recorded Investment	113		113		120
Unpaid Principal Balance	129		129		131
Related Allowance	0		0		0
Average Recorded Investment	122	129	121	127
Interest Income Recognized	0	0	0	0
Interest Recognized-Cash Method	0	0	0	0
Construction
Financing Receivable, Impaired [Line Items]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Average Recorded Investment	130	232	87	289
Interest Income Recognized	0	0	0	0
Interest Recognized-Cash Method	0	0	0	0
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
Interest Recognized-Cash Method	0	0	0	0
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	130	232	87	289
Interest Income Recognized	0	0	0	0
Interest Recognized-Cash Method	0	0	0	0
Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Recorded Investment	1,760		1,760		1,637
Unpaid Principal Balance	1,781		1,781		1,643
Average Recorded Investment	1,525	106	1,562	582
Interest Income Recognized	17	0	34	0
Interest Recognized-Cash Method	19	0	36	0
Recorded Investment	911		911		949
Unpaid Principal Balance	1,031		1,031		1,048
Related Allowance	107		107		145
Average Recorded Investment	1,123	1,161	1,065	1,208
Interest Income Recognized	0	0	0	0
Interest Recognized-Cash Method	0	0	0	0
Recorded Investment	2,671		2,671		2,586
Unpaid Principal Balance	2,812		2,812		2,691
Related Allowance	107		107		145
Average Recorded Investment	2,648	1,267	2,627	1,790
Interest Income Recognized	17	0	34	0
Interest Recognized-Cash Method	19	0	36	0
Commercial Business
Financing Receivable, Impaired [Line Items]
Recorded Investment	188		188		189
Unpaid Principal Balance	209		209		209
Average Recorded Investment	94	0	126	0
Interest Income Recognized	0	4	0	4
Interest Recognized-Cash Method	0	3	0	3
Recorded Investment	1,676		1,676		1,709
Unpaid Principal Balance	1,909		1,909		1,909
Related Allowance	1,226		1,226		1,259
Average Recorded Investment	1,726	1,776	1,720	1,776
Interest Income Recognized	0	0	0	0
Interest Recognized-Cash Method	0	0	0	0
Recorded Investment	1,864		1,864		1,898
Unpaid Principal Balance	2,118		2,118		2,118
Related Allowance	1,226		1,226		1,259
Average Recorded Investment	1,820	1,776	1,846	1,776
Interest Income Recognized	0	4	0	4
Interest Recognized-Cash Method	0	3	0	3
Home Equity and Second Mortgage
Financing Receivable, Impaired [Line Items]
Recorded Investment	96		96		254
Unpaid Principal Balance	110		110		268
Average Recorded Investment	169	251	197	167
Interest Income Recognized	0	1	1	2
Interest Recognized-Cash Method	0	1	1	1
Recorded Investment	0		0		22
Unpaid Principal Balance	0		0		22
Related Allowance	0		0		13
Average Recorded Investment	16	49	18	57
Interest Income Recognized	0	0	0	1
Interest Recognized-Cash Method	0	0	0	0
Recorded Investment	96		96		276
Unpaid Principal Balance	110		110		290
Related Allowance	0		0		13
Average Recorded Investment	185	300	215	224
Interest Income Recognized	0	1	1	3
Interest Recognized-Cash Method	0	1	1	1
Other Consumer
Financing Receivable, Impaired [Line Items]
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
Interest Recognized-Cash Method	0	0	0	0
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
Interest Recognized-Cash Method	0	0	0	0
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
Interest Recognized-Cash Method	$ 0	$ 0	$ 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

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