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Defined Benefit Plan, Curtailment, Years of Service

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Performance Bonus Expense

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Self funded medical plan expenses during period.

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Self Funded Medical Plan, Maximum Amount Paid Per Family

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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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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Amount of cost (credit) included in accumulated other comprehensive (income) loss expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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Amount of cost for defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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

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Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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Benefit Plans (Narrative) (Details) - USD ($) $ in Thousands		12 Months Ended
	Mar. 01, 2007	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Retirement Benefits [Abstract]
Employees contribution		100.00%
Corporation matching contribution, percent		100.00%
Employee contribution, percent		5.00%
Defined Contribution Plan Disclosure [Line Items]
Performance bonus expense		$ 1,070	$ 500	$ 454
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement		(128)	(269)	(235)
Plan expenses		764	743	713
Highest consecutive years of compensation	5 years
Years of service	10 years
Accumulated other comprehensive income includes net unrecognized pension cost before income taxes		3,412
Accumulated other comprehensive income expected to be amortized into benefit cost		23
Allocated Share-based Compensation Expense		171	45	38
Corporation self-funded medical plan		75
Medical expenses		2,445	2,695	2,324
Other Postretirement Benefits Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Plan expenses		$ 355	$ 356	$ 473
Safe Harbor 401(k) [Member]
Defined Contribution Plan Disclosure [Line Items]
Vesting percentage		100.00%
Fixed Income Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Investment allocation in securities		50.00%
Equity Collective Trust [Member]
Defined Benefit Plan Disclosure [Line Items]
Investment allocation in securities		50.00%