Pension and Postretirement Plans (Future Estimated Benefit Payments) (Details 4) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
2013	$ 75,081
2014	74,887
2015	75,207
2016	76,285
2017	78,657
2018-2022	429,337
Supplemental Executive Retirement Plan (SERP) [Member]
Defined Benefit Plan Disclosure [Line Items]
2013	4,454
2014	4,768
2015	4,846
2016	5,360
2017	5,511
2018-2022	30,867
Other Postretirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
2013	3,919
2014	4,081
2015	4,288
2016	4,521
2017	4,623
2018-2022	$ 25,998