Employee Benefit Plans (Details 5) (USD $)	Dec. 31, 2013
Medicare Part D Subsidy
2014	$ 2,121,000
2015	2,391,000
2016	2,650,000
2017	2,921,000
2018	3,222,000
Years 2019-2023	20,982,000
Pension Benefits
Expected benefits to be paid
2014	20,326,000
2015	14,820,000
2016	14,772,000
2017	15,814,000
2018	16,516,000
Years 2019-2023	92,643,000
Other Postretirement Benefits Before Medicare Subsidy
Pension and Other Employee Benefits
Funding requirement for 2014	30,000,000
Expected benefits to be paid
2014	32,158,000
2015	34,127,000
2016	36,056,000
2017	37,921,000
2018	39,824,000
Years 2019-2023	217,871,000
Other Postretirement Benefits Before Medicare Subsidy | Minimum
Pension and Other Employee Benefits
Funding requirement for 2014	$ 1,100,000