Accumulated Other Comprehensive Loss (Components of AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ (623,336)	$ (537,341)
Other comprehensive income (loss) before reclassifications	35,099	35,346
Amounts reclassified from AOCL	1,659	1,840
Other comprehensive income	36,758	37,186
Ending balance	(586,578)	(500,155)
Accumulated Other Comprehensive Gain (Loss), accumulated Net Gain (Loss) from Net investment hedge	(800)	(12,500)
Foreign currency translation items
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(485,568)	(413,422)
Other comprehensive income (loss) before reclassifications	36,171	33,757
Amounts reclassified from AOCL	0	0
Other comprehensive income	36,171	33,757
Ending balance	(449,397)	(379,665)
Pension and other post-retirement effects
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(136,530)	(120,461)
Other comprehensive income (loss) before reclassifications	(1,152)	1,060
Amounts reclassified from AOCL	1,636	1,726
Other comprehensive income	484	2,786
Ending balance	(136,046)	(117,675)
Cash flow hedging activity
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(1,238)	(3,458)
Other comprehensive income (loss) before reclassifications	80	529
Amounts reclassified from AOCL	23	114
Other comprehensive income	103	643
Ending balance	(1,135)	(2,815)
Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	$ 3,900	$ 3,500	$ 3,400	$ 2,700