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Retirement Plans SERP (Details) - Supplemental Employee Retirement Plans, Defined Benefit - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Annual Benefit Amount	$ 50,000
Year of Benefit	20 years
Defined Benefit Plan, Other Information-Number of Employees Covered	2
Defined Benefit Plan, Other Cost (Credit)	$ 32,000	$ 36,000	$ 40,000
Liability, Defined Benefit Plan	$ 465,000	$ 533,000

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- Definition

Amount of Annual Benefit to be paid

+ References

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- Definition

Number of years benefit will be paid after retirement.

+ References

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- Definition

Amount of defined benefit plan cost (credit), classified as other.

+ References

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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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- Definition

Description of defined benefit pension and other postretirement plans. Includes, but is not limited to, employee group covered, type of benefit formula, type of benefits, cost sharing arrangement, funding policy, type of assets held, significant nonbenefit liabilities and information pertaining to multiple employer plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=112275985&loc=d3e4179-114921

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- Definition

Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(15))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Topic 944
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