Defined Benefit Plans (Net Periodic Benefit Costs) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 20	$ 36
Interest cost	45	65
Expected return on plan assets	(68)	(63)
Amortization of net (gain) or loss		(15)
Net periodic benefit (income) expense	(3)	23
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		1
Interest cost		4
Amortization (accretion) of prior service cost	(5)	$ (5)
Net periodic benefit (income) expense	$ (5)