Employee Pension Plans (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Summary of net periodic benefit cost
Interest cost	$ 1,011	$ 1,030	$ 2,022	$ 2,060
Expected return on plan assets	(1,256)	(1,192)	(2,512)	(2,384)
Amortization of net loss	1,460	1,077	2,920	2,154
Net periodic benefit cost	$ 1,215	$ 915	2,430	1,830
Company contribution			1,400	$ 1,500
Expected contributions remainder of current fiscal year			$ 1,300