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Deferred Compensation Plans (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Deferred compensation arrangement with individual, cash awards granted, percentage	90.00%
Cash surrender value of life insurance	$ 894,000	$ 207,000
Gain on company owned life insurance	$ 67,000	14,000	$ 0
Restricted Stock
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Deferred compensation arrangement, deferred shares	97,011
Other noncurrent liabilities
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Deferred compensation liability, current and noncurrent	$ 866,000	208,000
Other income
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Gain on company owned life insurance	$ 66,400	$ 13,900

X

- Definition

Deferred Compensation Arrangement, Deferred Shares

+ References

No definition available.

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- Definition

Deferred Compensation Arrangements, Maximum Participant Total Compensation Deferral, Percent

+ References

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X

- Definition

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 4
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6812-107765

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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.

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X

- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

+ References

No definition available.

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- Definition

The change in cash surrender or contract value during the period which adjusted the amount of premiums paid in determining the expense or income recognized under the contract for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 30
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6384439&loc=d3e42048-111605

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