Accrued Expenses and Other Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Accrued Expenses
Salaries and wages	$ 88,592	$ 99,032
Deferred compensation	2,874	2,252
Pension benefits	3,808	3,790
Other postretirement benefits	1,634	1,624
Other employee benefits	23,843	8,956
Insurance obligations	140,528	157,014
Environmental liabilities	3,839	3,791
Operating taxes	96,813	101,649
Income taxes	444	3,378
Interest	37,128	31,218
Customer deposits	62,035	61,869
Deferred revenue	14,556	13,038
Restructuring liabilities	2,391	12,333
Other	38,377	43,408
Total	516,862	543,352
Non-Current Liabilities
Salaries and wages	0	0
Deferred compensation	44,702	41,691
Pension benefits	466,721	484,892
Other postretirement benefits	19,536	20,002
Other employee benefits	5,040	9,706
Insurance obligations	221,254	213,256
Environmental liabilities	5,911	6,554
Operating taxes	0	0
Income taxes	23,467	22,366
Interest	0	0
Customer deposits	4,688	5,085
Deferred revenue	0	0
Restructuring liabilities	0	0
Other	25,913	26,043
Total	817,232	829,595
Total
Salaries and wages	88,592	99,032
Deferred compensation	47,576	43,943
Pension benefits	470,529	488,682
Other postretirement benefits	21,170	21,626
Other employee benefits	28,883	18,662
Insurance obligations	361,782	370,270
Environmental liabilities	9,750	10,345
Operating taxes	96,813	101,649
Income taxes	23,911	25,744
Interest	37,128	31,218
Customer deposits	66,723	66,954
Deferred revenue	14,556	13,038
Restructuring liabilities	2,391	12,333
Other	64,290	69,451
Total	$ 1,334,094	$ 1,372,947