Employee Stock Ownership Plan - Additional Information (Detail)	12 Months Ended
Dec. 31, 2016 USD ($) Age shares	Dec. 31, 2015 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Noncontributory employee stock ownership plan, service period eligibility	12 months
Noncontributory employee stock ownership plan, age eligibility \| Age	21
Allocations, as a percentage of eligible participant compensation	25.00%
Participant accounts vested after two years	30.00%
Participant accounts vested after three years	40.00%
Participant accounts vested each year, from fourth year till 100% vested	20.00%
Participant accounts, total vested	100.00%
Allocated shares \| shares	113,161
Contributions to the plan	$ 67,000	$ 50,000
Dividends on the company's stock held by the ESOP	$ 0	$ 0

Employee Stock Ownership Plan Esop Allocation Percentage

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- Definition

Employee Stock Ownership Plan Esop Minimum Age Qualification

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No definition available.

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- Definition

Employee Stock Ownership Plan Esop Participant Accounts Vested After Three Years Percentage

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No definition available.

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- Definition

Employee Stock Ownership Plan Esop Participant Accounts Vested After Two Years Percentage

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No definition available.

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- Definition

Employee Stock Ownership Plan Esop Participant Accounts Vested Each Year From Fourth Year Till Hundred Percentage Vested Percentage

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No definition available.

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- Definition

Employee Stock Ownership Plan Esop Participant Accounts Vested Percentage

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No definition available.

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- Definition

This item represents the amount of cash contributions during the period made by the entity to the Employee Stock Ownership Plan (ESOP).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65895303&loc=d3e17540-113929

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- Definition

Dividends paid on stock held by an employee stock ownership plan.

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+ Details

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- Definition

The shares or units in an ESOP trust that have been assigned to individual participant accounts based on a known formula. IRS rules require allocations to be nondiscriminatory generally based on compensation, length of service, or a combination of both. For any particular participant such shares or units may be vested, unvested, or partially vested.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=65895303&loc=d3e17540-113929

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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.

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No definition available.

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