Other Comprehensive Income (Loss) - After-tax Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Foreign currency items
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ (21,079)	$ (16,507)
Net current period change	289	(3,008)
Reclassification adjustments for losses reclassified into income	0	0
Ending Balance	(20,790)	(19,515)
Pension and postretirement benefits plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(18,575)	(20,781)
Reclassification adjustments for losses reclassified into income	109	61
Ending Balance	(18,466)	(20,720)
Accumulated other comprehensive loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(39,654)	(37,288)
Net current period change	289	(3,008)
Reclassification adjustments for losses reclassified into income	109	61
Ending Balance	$ (39,256)	$ (40,235)