Goodwill and Other Intangible Assets (Net intangible assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Intangible Assets, Net:
Cost	$ 838,764	$ 626,713
Acquisitions	0	264,165
Currency translation	(28,432)	(52,114)
Accumulated amortization	555,873	534,572
Net Value	254,459	304,192	$ 79,318
Customer relationships
Intangible Assets, Net:
Cost	588,716	354,768
Acquisitions	0	258,875
Currency translation	(18,736)	(24,927)
Accumulated amortization	334,276	317,593
Net Value	235,704	271,123	33,917
Patents
Intangible Assets, Net:
Cost	243,258	270,466
Acquisitions	0	0
Currency translation	(9,236)	(27,208)
Accumulated amortization	220,598	216,273
Net Value	13,424	26,985	$ 44,591
Other
Intangible Assets, Net:
Cost	6,790	1,479
Acquisitions	0	5,290
Currency translation	(460)	21
Accumulated amortization	999	706
Net Value	$ 5,331	$ 6,084