Defined Benefit Pension Plan (Net Pension Cost (Credit)) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Defined Benefit Pension Plan [Abstract]
Service cost	$ 317	$ 342	$ 951	$ 1,027
Interest cost	446	396	1,339	1,190
Expected return on plan assets	(750)	(818)	(2,251)	(2,456)
Amortization of net actuarial loss	88		264
Net pension cost (credit)	$ 101	$ (80)	$ 303	$ (239)