Allowance for Loan Losses - Allowance for Loan Losses by Portfolio Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
ALLOWANCE FOR LOAN LOSSES:
Beginning Balance	$ 3,205	$ 2,925
(Charge-offs)	(658)	(392)
Recoveries	79	61
Provision	1,597	611
Ending Balance	4,223	3,205
Individually evaluated for impairment	1,534	676
Collectively evaluated for impairment	2,689	2,529
Mortgage Loans on Real Estate
ALLOWANCE FOR LOAN LOSSES:
Beginning Balance	2,778	2,465
(Charge-offs)	(521)	(313)
Recoveries	27	36
Provision	1,218	590
Ending Balance	3,502	2,778
Individually evaluated for impairment	1,256	665
Collectively evaluated for impairment	2,246	2,113
Commercial and Industrial
ALLOWANCE FOR LOAN LOSSES:
Beginning Balance	323	256
(Charge-offs)	(9)
Provision	285	67
Ending Balance	599	323
Individually evaluated for impairment	278
Collectively evaluated for impairment	321	323
Consumer and Other Loans
ALLOWANCE FOR LOAN LOSSES:
Beginning Balance	104	204
(Charge-offs)	(128)	(79)
Recoveries	52	25
Provision	94	(46)
Ending Balance	122	104
Individually evaluated for impairment		11
Collectively evaluated for impairment	$ 122	$ 93

A valuation allowance for financing receivables that are expected to be uncollectible.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of direct write-downs of financing receivables charged against the allowance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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