Components of Net Periodic Benefit Cost (Details 2) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Net pension cost of plans
Service cost				$ 100
Interest cost	$ 1,931	$ 1,916	$ 3,862	3,855
Expected return on plan assets	(2,159)	(2,109)	(4,319)	(4,218)
Recognized actuarial loss	1,557	921	3,114	1,842
Net periodic benefit cost	$ 1,329	$ 728	$ 2,657	$ 1,579