Employee Benefit Plans - Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income from Discontinued Operations, net
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost		$ 4,000	$ 14,900
Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1,484	3,923	8,452
Interest cost	3,319	10,707	16,682
Expected return on plan assets	(4,027)	(15,258)	(25,302)
Amortization of prior service cost	13	576	1,296
Amortization of losses	3,733	6,542	20,097
Amortization of negative plan amendment	0	0	0
Curtailment expense	0	0	60
Settlement expense	0	0	817
Net periodic benefit cost	4,522	6,490	22,102
Postretirement
Defined Benefit Plan Disclosure [Line Items]
Service cost	11	402	1,056
Interest cost	52	537	937
Expected return on plan assets	0	0	0
Amortization of prior service cost	0	8	66
Amortization of losses	12	288	675
Amortization of negative plan amendment	0	(137)	(105)
Curtailment expense	0	0	0
Settlement expense	0	0	0
Net periodic benefit cost	$ 75	$ 1,098	$ 2,629