Benefit Plans (Accrued Pension Costs) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Retirement Benefits [Abstract]
Accumulated Benefit Obligation, end of year	$ 25,457	$ 22,515
Change in Projected Benefit Obligation
Projected benefit obligation, beginning of period	28,624	25,935
Service cost	1,001	995
Interest cost	1,228	1,155
Actuarial (Gain) Loss	2,474	1,031
Benefits Paid	(507)	(492)
Projected benefit obligation, end of period	32,820	28,624
Change in Plan Assets
Plan assets at fair value, beginning of period	0	0
Company contributions	507	492
Benefits Paid	(507)	(492)
Plan assets at fair value, end of period	0	0
Unfunded Status of the Plan	(32,820)	(28,624)
Amounts Recognized in Accumulated Other Comprehensive Income
Net loss	7,745	5,561
Total Pension Cost	$ 7,745	$ 5,561