Pension Plan (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Compensation and Retirement Disclosure [Abstract]
Service cost	$ 52	$ 72	$ 120	$ 145
Interest cost on projected benefit obligation	810	877	1,697	1,753
Expected return on plan assets	(1,380)	(1,496)	(2,849)	(2,992)
Net amortization and deferral	805	427	1,617	855
Net periodic pension (income) cost	$ 287	$ (120)	$ 585	$ (239)