Goodwill and Other Intangible Assets (Schedule of Changes in Intangible Assets and Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Amortized intangible assets:
Beginning balance	$ 55,441	$ 66,454
Amortization	(6,235)	(6,864)
Other Changes		(4,149)
Currency Translation
Ending balance	49,206	55,441
Beginning balance	166,796	160,375
Amortization
Other Changes
Currency Translation	(2,414)	6,421
Ending balance	$ 164,382	166,796
AEC Trade Names [Member]
Amortized intangible assets:
Amortization life in year	15 years
Beginning balance	$ 15	20
Amortization	(4)	(5)
Other Changes
Currency Translation
Ending balance	$ 11	15
AEC Technology [Member]
Amortized intangible assets:
Amortization life in year	15 years
Beginning balance	$ 80	104
Amortization	(24)	(24)
Other Changes
Currency Translation
Ending balance	$ 56	80
Customer Contracts [Member]
Amortized intangible assets:
Amortization life in year	6 years
Beginning balance	$ 12,369	17,859
Amortization	(2,913)	(3,279)
Other Changes		(2,211)
Currency Translation
Ending balance	$ 9,456	12,369
Customer Relationships [Member]
Amortized intangible assets:
Amortization life in year	15 years
Beginning balance	$ 42,767	47,009
Amortization	(3,229)	(3,281)
Other Changes		(961)
Currency Translation
Ending balance	$ 39,538	42,767
Other Intangible Assets [Member]
Amortized intangible assets:
Amortization life in year	5 years
Beginning balance	$ 210	1,462
Amortization	(65)	(275)
Other Changes		(977)
Currency Translation
Ending balance	145	210
MC Goodwill [Member]
Amortized intangible assets:
Beginning balance	71,066	64,645
Amortization
Other Changes
Currency Translation	(2,414)	6,421
Ending balance	68,652	71,066
AEC Goodwill [Member]
Amortized intangible assets:
Beginning balance	95,730	95,730
Amortization
Other Changes
Currency Translation
Ending balance	$ 95,730	$ 95,730