Pension Plans (Components of Pension Cost) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 0
Interest cost	345	363
Expected return on plan assets	(325)	(325)
Amortization of net (gain)/loss	171	178
Net periodic pension cost	191	216
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	306	308
Expected return on plan assets	(325)	(325)
Amortization of net (gain)/loss	210	219
Net periodic pension cost	191	202
SERP
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	39	55
Expected return on plan assets	0	0
Amortization of net (gain)/loss	(39)	(41)
Net periodic pension cost	$ 0	$ 14