Employee Benefit Plans (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2013 item	Dec. 31, 2012 item	Dec. 31, 2011
Amounts Recognized in the Balance Sheet
Long-Term Liabilities	$ 33,554,000	$ 38,864,000
Postretirement Benefits Other than Pensions
Components of Net Periodic Benefit Cost
Current period service cost	1,739,000	1,513,000	1,403,000
Interest Cost	1,500,000	1,537,000	1,717,000
Amortization of net obligation at transition			(632,000)
Amortization of net loss	641,000	824,000	448,000
Net periodic pension cost	3,880,000	3,874,000	4,200,000
Number of retirees and their dependents to whom benefits under the plan are provided	270	265
Change in Benefit Obligation
Benefit Obligation at Beginning of Year	40,168,000	39,969,000	31,947,000
Service Cost	1,739,000	1,513,000	1,403,000
Interest Cost	1,500,000	1,537,000	1,717,000
Actuarial (Gain)/ Loss	(7,618,000)	(2,073,000)	6,015,000
Benefits Paid	(794,000)	(778,000)	(1,113,000)
Benefit Obligation at End of Year	34,995,000	40,168,000	39,969,000
Change in Plan Assets
Funded Status at End of Year	(34,995,000)	(40,168,000)	(39,969,000)
Amounts Recognized in the Balance Sheet
Current Liabilities	1,441,000	1,304,000	1,261,000
Long-Term Liabilities	33,554,000	38,864,000	38,708,000
Amounts Recognized in the Balance Sheet	34,995,000	40,168,000	39,969,000
Amounts Recognized in Accumulated Other Comprehensive Income
Net Actuarial Loss	3,010,000	11,269,000	14,166,000
Amounts Recognized in Accumulated Other Comprehensive Income	3,010,000	11,269,000	14,166,000
Other changes in qualified plan assets and benefit obligations recognized in other comprehensive income
Net (Gain)/Loss	(7,618,000)	(2,073,000)	6,015,000
Amortization of net obligation at transition			(632,000)
Amortization of Net Loss	(641,000)	(824,000)	(448,000)
Total Recognized in Other Comprehensive Income	(8,259,000)	(2,897,000)	4,935,000
Total Recognized in Net Periodic Benefit Cost and Other Comprehensive Income	(4,379,000)	977,000	9,135,000
Weighted-average assumptions used to determine projected pension benefit obligations
Discount Rate (as a percent)	4.75%	4.00%	4.25%
Discount Rate beginning of year (as a percent)	4.00%	4.25%	5.75%
Health Care Cost Trend Rate for Medical Benefits Assumed for Next Year (as a percent)	6.50%	7.00%	8.00%
Rate to which the cost trend rate is assumed to decline (the Ultimate Trend Rate) (as a percent)	4.50%	5.00%	5.00%
Year that the rate reaches the Ultimate Trend Rate	2018	2015	2015
Postretirement Benefits Other than Pensions | Medical, before age 65
Weighted-average assumptions used to determine projected pension benefit obligations
Subsidy limit which should not exceed aggregate annual amount	$ 648,000
Annual increase in subsidy limit (as a percent)	3.50%
Postretirement Benefits Other than Pensions | Medical, age 65 and older
Weighted-average assumptions used to determine projected pension benefit obligations
Percentage of the expected annual fully-insured premium by which subsidy is limited	60.00%