Miscellaneous Income, Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Other Income and Expenses [Abstract]
Gains on sales of operating property and equipment	$ 3,045	$ 2,909	$ 1,020
Business interruption insurance recoveries	0	808	2,743
Contract settlement	55	3,014	0
Foreign currency translation benefit	0	0	1,904
Foreign currency transaction gains/(losses)	1,945	(210)	40
Rabbi trust investment income	632	2,726	4,475
Other, net	4,479	4,366	5,190
Total	$ 10,156	$ 13,613	$ 15,372