Pension and Other Post-Retirement Benefit Plans (Net Periodic Benefit Costs) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Pension Plans [Member]
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	$ 0	$ 0	$ 0	$ 0
Interest cost	9,879,000	8,989,000	19,758,000	17,978,000
Expected return on plan assets	(11,528,000)	(11,498,000)	(23,056,000)	(22,996,000)
Amortization of prior service cost	0	0	0	0
Amortization of net (gain) loss	0	3,074,000	(1,000)	6,148,000
Net periodic benefit cost	(1,649,000)	565,000	(3,299,000)	1,130,000
Employer contributions	300,000		1,000,000
Estimated future employer contributions			5,300,000
Post-Retirement Healthcare Plans [Member]
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	60,000	69,000	120,000	138,000
Interest cost	71,000	66,000	142,000	132,000
Expected return on plan assets	0	0	0	0
Amortization of prior service cost	(872,000)	(1,413,000)	(1,744,000)	(2,826,000)
Amortization of net (gain) loss	80,000	104,000	160,000	208,000
Net periodic benefit cost	$ (661,000)	$ (1,174,000)	$ (1,322,000)	$ (2,348,000)