Defined benefit pension plan minimum eligible age of employee.

No definition available.

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- Definition

Defined contribution plan minimum eligible age of employee.

+ References

No definition available.

+ Details

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- Definition

Defined contribution plan percentage of employer matching contribution of first one percent of employee contribution.

+ References

No definition available.

+ Details

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- Definition

Defined contribution plan stated percentage of employees contribution.

+ References

No definition available.

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- Definition

Employee matching contribution vesting period under plan.

+ References

No definition available.

+ Details

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- Definition

Number of highest paid consecutive periods of service for calculation of average compensation related to benefits.

+ References

No definition available.

+ Details

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- Definition

Period of service credit by employee.

+ References

No definition available.

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- Definition

Services completed by eligible participant under plan.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award vesting percentage under award requisite service period.

+ References

No definition available.

+ Details

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

+ References

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(ii)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 1
-Subparagraph (d)(5)(iv)(01)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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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.

+ References

No definition available.

+ Details

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

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- Definition

The amount of plan compensation cost recognized during the period.

+ 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 (c)
-URI http://asc.fasb.org/extlink&oid=65895303&loc=d3e17540-113929

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- Definition

Sum of the allocated, committed-to-be-released and suspense shares of the entity held by the plan.

+ 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=96867065&loc=d3e5070-113901

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Benefit Plans - Additional Information (Detail) - USD ($)			12 Months Ended
	Mar. 08, 2018	Jan. 01, 2000	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Minimum eligibility for full-time employees, age			21 years
Number of highest-paid consecutive years for benefits			5 years
Employer contributions			$ 1,800,000	$ 0
Amount of accumulated benefit obligation for the defined benefit pension plan			$ 5,300,000	5,800,000
Percentage of first employee compensation for which company makes matching contribution			1.00%
Company contribution on employee specific contribution			50.00%
Number of hours in service required for the contribution to be allocated			1000 hours
Minimum eligibility for employees under 401(k) Plan age			19 years
Number of plan service years after which employer matching contribution vest			2 years
Expense attributable to the Plan amounted			$ 740,000	482,000
Percentage of vested participants		100.00%
Participants years of credited service		2 years
Compensation expense for ESOP			$ 0	$ 0
Shares of the Company held by the ESOP (in shares)			230,846	247,283
Minimum
Defined Benefit Plan Disclosure [Line Items]
Period of service credit by employee			1 year
Percentage of employee for which company makes specified contribution			2.00%
Maximum
Defined Benefit Plan Disclosure [Line Items]
Percentage of employee for which company makes specified contribution			6.00%
Subsequent Event
Defined Benefit Plan Disclosure [Line Items]
Employer contributions	$ 205,000