Pension and Other Post-Retirement Benefits Estimated Net Benefit Cost Amortizations (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated Amortization of Net Transition Obligation	$ 0
Estimated Amortization of Prior Service Cost	(806)
Estimated Amortization of Net Loss	394
Total Estimated Net Periodic Benefit Cost Amortizations	(412)
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated Amortization of Net Transition Obligation	0
Estimated Amortization of Prior Service Cost	74
Estimated Amortization of Net Loss	1,964
Total Estimated Net Periodic Benefit Cost Amortizations	$ 2,038