Allowance for Loan Losses - Allowance for Loan Losses by Portfolio Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
ALLOWANCE FOR LOAN LOSSES:
Beginning Balance	$ 4,223	$ 3,205
Reclassification of allowance related to sold loans	(27)
(Charge-offs)	(946)	(658)
Recoveries	326	79
Provision	287	1,597
Ending Balance	3,863	4,223
Individually evaluated for impairment	895	1,534
Collectively evaluated for impairment	2,968	2,689
Mortgage Loans on Real Estate
ALLOWANCE FOR LOAN LOSSES:
Beginning Balance	3,502	2,778
(Charge-offs)	(735)	(521)
Recoveries	254	27
Provision	297	1,218
Ending Balance	3,318	3,502
Individually evaluated for impairment	803	1,256
Collectively evaluated for impairment	2,515	2,246
Commercial and Industrial
ALLOWANCE FOR LOAN LOSSES:
Beginning Balance	599	323
(Charge-offs)	(158)	(9)
Recoveries	61
Provision	(9)	285
Ending Balance	493	599
Individually evaluated for impairment	92	278
Collectively evaluated for impairment	401	321
Consumer and Other Loans
ALLOWANCE FOR LOAN LOSSES:
Beginning Balance	122	104
Reclassification of allowance related to sold loans	(27)
(Charge-offs)	(53)	(128)
Recoveries	11	52
Provision	(1)	94
Ending Balance	52	122
Collectively evaluated for impairment	$ 52	$ 122

Reclassification of Allowances for Loan Losses Related to Sold Loans

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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-URI http://asc.fasb.org/extlink&oid=66008989&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=66008989&loc=SL6953423-111524

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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
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-Paragraph 11B
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Paragraph 11B
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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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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- Definition

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

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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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