Components of Net Periodic Pension Cost (Schedule of Net Benefit Costs) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Average daily balance during the year
Service cost
Interest cost	91	113
Expected return on plan assets	(196)	(174)
Net amortization	75	89
Total periodic pension cost	$ (30)	$ 28

Amount of cost recognized for passage of time related to defined benefit plan.

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Name:	us-gaap_DefinedBenefitPlanInterestCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration