Pension and Other Post-Retirement Benefits Benefit Plan Obligation Table (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation	$ 13,322,000	$ 12,842,000	$ 13,443,000
Defined Benefit Plan, Service Cost	548,000	599,000	567,000
Defined Benefit Plan, Interest Cost	538,000	623,000	574,000
Defined Benefit Plan, Actuarial Gain (Loss)	(275,000)	901,000
Defined Benefit Plan, Benefits Paid	(424,000)	(376,000)
Defined Benefit Plan, Fair Value of Plan Assets	7,133,000	6,465,000	6,475,000
Defined Benefit Plan, Actual Return on Plan Assets	977,000	46,000
Defined Benefit Plan, Contributions by Employer	22,000	235,000
Defined Benefit Plan, Funded Status of Plan	(6,189,000)	(6,377,000)
Pension And Other Postretirement Defined Benefit Plans Non-Current Assets	0	0
Pension and Other Postretirement Defined Benefit Plans, Current Liabilities	0	0
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent	(6,189,000)	(6,377,000)
Defined Benefit Plan, Amounts Recognized in Balance Sheet	(6,189,000)	(6,377,000)
Defined Benefit Plan, Contributions by Plan Participants	93,000	85,000
Defined Benefit Plan, Plan Amendments	0	(2,433,000)
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation	66,501,000	49,102,000	40,758,000
Defined Benefit Plan, Service Cost	2,020,000	1,523,000	1,668,000
Defined Benefit Plan, Interest Cost	2,570,000	2,134,000	2,175,000
Defined Benefit Plan, Actuarial Gain (Loss)	14,494,000	5,878,000
Defined Benefit Plan, Benefits Paid	(1,685,000)	(1,191,000)
Defined Benefit Plan, Fair Value of Plan Assets	45,406,000	36,783,000	36,990,000
Defined Benefit Plan, Actual Return on Plan Assets	9,723,000	(216,000)
Defined Benefit Plan, Contributions by Employer	585,000	1,200,000
Defined Benefit Plan, Funded Status of Plan	(21,095,000)	(12,319,000)
Pension And Other Postretirement Defined Benefit Plans Non-Current Assets	0	0
Pension and Other Postretirement Defined Benefit Plans, Current Liabilities	0	0
Pension and Other Postretirement Defined Benefit Plans, Liabilities, Noncurrent	(21,095,000)	(12,319,000)
Defined Benefit Plan, Amounts Recognized in Balance Sheet	$ (21,095,000)	$ (12,319,000)