Defined Benefit Plans (Net Periodic Benefit Costs) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 33	$ 20
Interest cost	40	45
Expected return on plan assets	(57)	(68)
Settlement gain	(49)
Net periodic benefit income	(33)	(3)
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1
Interest cost	2
Accretion of prior service cost	(5)	(5)
Net periodic benefit income	$ (2)	$ (5)