Components of Net Periodic Benefit Cost (Details Textual) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	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	$ 1,100	$ 1,000
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	161
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Contributions by Employer	$ 1,300