Accumulated Other Comprehensive Income (Loss) - Changes in Components (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Accumulated Other Comprehensive Income (Loss)
Balance	$ 393,991
Total other comprehensive income (loss)	2,831	$ (9,242)
Balance	392,544
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss)
Balance	(41,630)	(27,510)
Other comprehensive income (loss) before reclassifications	2,294	(9,524)
Amounts reclassified from other comprehensive income (loss)	537	282
Total other comprehensive income (loss)	2,831	(9,242)
Balance	(38,799)	(36,752)
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss)
Balance	(11,070)	1,943
Other comprehensive income (loss) before reclassifications	3,097	(10,296)
Total other comprehensive income (loss)	3,097	(10,296)
Balance	(7,973)	(8,353)
Defined Benefit Pension Plan Adjustments
Accumulated Other Comprehensive Income (Loss)
Balance	(30,474)	(30,358)
Other comprehensive income (loss) before reclassifications	(17)	310
Amounts reclassified from other comprehensive income (loss)	541	500
Total other comprehensive income (loss)	524	810
Balance	(29,950)	(29,548)
Derivatives
Accumulated Other Comprehensive Income (Loss)
Balance	(86)	905
Other comprehensive income (loss) before reclassifications	(786)	462
Amounts reclassified from other comprehensive income (loss)	(4)	(218)
Total other comprehensive income (loss)	(790)	244
Balance	$ (876)	$ 1,149