Pension and Post-Retirement Benefit Costs (Additional Information) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Salaried Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contribution	$ 0	$ 965
Estimated future employer contributions for next fiscal year	0
Wage Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contribution	349	$ 580
Estimated future employer contributions for next fiscal year	$ 0