Number of days for demand deposits with financial institutions to be considered cash and cash equivalent.

No definition available.

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- Definition

Par value of Federal Home Loan Bank Stock.

+ References

No definition available.

+ Details

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- Definition

Minimum balance requirement to perform detailed loan review.

+ References

No definition available.

+ Details

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- Definition

Percentage of insurance commission revenue of total revenue.

+ References

No definition available.

+ Details

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- Definition

Represents the number of days past due for loans and leases to be considered nonaccrual.

+ References

No definition available.

+ Details

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- Definition

Number of days secured residential real estate loans are past due to receive an assessment of value.

+ References

No definition available.

+ Details

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- Definition

Number of days unsecured loans are past due to recognize charge off.

+ References

No definition available.

+ Details

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- Definition

Number of days all other loans are past due to recognize an impairment.

+ References

No definition available.

+ Details

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- Definition

Significant Accounting Policies [Line Items]

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No definition available.

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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

+ References

No definition available.

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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No definition available.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2018 USD ($) Segment $ / shares	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018 USD ($)
Significant Accounting Policies [Line Items]
Allowance for loan losses related to commercial, commercial real estate and farm real estate loans	$ 750,000
Number of days reaching which loans are considered for nonaccrual status	90 days
Federal Home Loan Bank par value \| $ / shares	$ 100
Number of operating segments \| Segment	1
Right to use asset	$ 3,000,000
Lease obligation	$ 3,000,000
Unsecured Debt [Member]
Significant Accounting Policies [Line Items]
Retail loans past due charge off period	90 days
Secured Debt [Member]
Significant Accounting Policies [Line Items]
Residential real estate loans past due assessment of value period	180 days
Other Debt [Member]
Significant Accounting Policies [Line Items]
Loans past due charged down to the net realizable value period	90 days
Retained Earnings [Member] \| Accounting Standards Update 2016-01 [Member]
Significant Accounting Policies [Line Items]
Change in accounting principle for adoption of ASU 2016-01				$ 278,000
Accumulated Other Comprehensive Income (Loss) [Member] \| Accounting Standards Update 2016-01 [Member]
Significant Accounting Policies [Line Items]
Change in accounting principle for adoption of ASU 2016-01				$ (278,000)
Maximum [Member]
Significant Accounting Policies [Line Items]
Percentage of insurance commission revenue of total revenue	1.00%	1.00%	1.00%
Original maturities for cash and cash equivalents	90 days
Estimated useful life of intangible assets	12 years
Maximum [Member] \| Furniture and Equipment [Member]
Significant Accounting Policies [Line Items]
Estimated useful life of asset	7 years
Maximum [Member] \| Buildings and Improvements [Member]
Significant Accounting Policies [Line Items]
Estimated useful life of asset	50 years
Maximum [Member] \| WSP [Member]
Significant Accounting Policies [Line Items]
Percentage of insurance commission revenue of total revenue	1.00%	1.00%	1.00%
Maximum [Member] \| CIVB Risk Management, Inc. [Member]
Significant Accounting Policies [Line Items]
Percentage of insurance commission revenue of total revenue	1.00%	1.00%
Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated useful life of intangible assets	5 years
Minimum [Member] \| Furniture and Equipment [Member]
Significant Accounting Policies [Line Items]
Estimated useful life of asset	3 years
Minimum [Member] \| Buildings and Improvements [Member]
Significant Accounting Policies [Line Items]
Estimated useful life of asset	7 years