Components of Net Periodic Benefit Cost (Details Textual) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Defined Benefits Plan Estimated Future Employer Contributions In Next Fiscal Year		$ 1,800
Defined Benefit Plan, Expected Future Benefit Payments, Next Rolling Twelve Months		1,100
Defined Contribution Plan Employer Accrued Discretionary Contribution Amount	$ 719
Post Retirement Health Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefits Plan Estimated Future Employer Contributions In Next Fiscal Year		$ 247
Defined Benefit Plan, Contributions by Employer	110
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Contributions by Employer	$ 554