Allowance for Loan Losses - Loan Receivables Evaluated for Impairment Individually and Collectively by Segment (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	$ 10,032	$ 10,415
Collectively evaluated for impairment	394,820	374,594
Total Gross Loans	404,852	385,009
Mortgage Loans on Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	9,940	10,323
Collectively evaluated for impairment	345,383	328,118
Total Gross Loans	355,323	338,441
Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	92	92
Collectively evaluated for impairment	46,113	42,932
Total Gross Loans	46,205	43,024
Consumer and Other Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Collectively evaluated for impairment	3,324	3,544
Total Gross Loans	$ 3,324	$ 3,544

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

The balance of financing receivables 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 (h)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

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