Pension and Post-Retirement Benefit Costs (Components of Net Periodic Benefit Cost) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 275	$ 250	$ 815	$ 754
Interest cost	515	645	1,531	1,936
Expected return on plan assets	(713)	(623)	(2,140)	(1,867)
Amortization of prior service cost	74	74	223	223
Amortization of net loss	510	445	1,449	1,329
Net periodic benefit cost	661	791	1,878	2,375
Post-Retirement Healthcare
Defined Benefit Plan Disclosure [Line Items]
Service cost	2	2	7	7
Interest cost	147	185	442	555
Expected return on plan assets	0	0	0	0
Amortization of prior service cost	21	21	63	63
Amortization of net loss	90	44	269	132
Net periodic benefit cost	$ 260	$ 252	$ 781	$ 757