Pension Plan and Post-Retirement Benefits (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Net pension (benefit) / cost recognized for the Pension Plans
Service cost for benefits earned during the quarter	$ 1,125	$ 1,215
Interest cost on projected benefit obligations	7,079	6,900
Expected return on plan assets	(9,340)	(10,236)
Amortization of net loss	1,157	534
Amortization of prior service cost	24	69
Net pension cost (benefit) - Company plan	45	(1,518)
Net pension cost - multi-employer plan	88	87
Total net pension cost (benefit)	133	(1,431)
Defined Contribution Plan
Suspended contributions	2,200
Defined contribution plan expense recognized	3,600	$ 5,000
Victory Acquisition
Defined Contribution Plan
Contributions offset	$ 800