Defined Pension Plans (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Defined Benefit Plan Disclosure [Line Items]
Pension period			30 years
Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension costs	$ 1,178	$ 1,049	$ 3,543	$ 3,147
Unfunded Supplemental Executive Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension costs	$ 195	$ 255	$ 586	$ 766