Loans - Recorded Investment in Loans Related to Balance in Allowance for Possible Loan Losses by Portfolio Segment (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually evaluated for specific impairment	$ 11,576	$ 10,306
Loans collectively evaluated for general impairment	461,934	419,016
Total Gross Loans	473,510	429,322
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually evaluated for specific impairment	11,432	10,306
Loans collectively evaluated for general impairment	360,528	337,668
Total Gross Loans	371,960	347,974
Real Estate Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually evaluated for specific impairment	144	0
Loans collectively evaluated for general impairment	88,078	67,328
Total Gross Loans	88,222	67,328
Consumer Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans collectively evaluated for general impairment	13,328	14,020
Total Gross Loans	$ 13,328	$ 14,020

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=118936363&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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

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