Goodwill- Goodwill and Intangible Assets, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Carrying amount of goodwill by reportable segment
Increase (Decrease) in Other Current Assets	$ 845	$ 3,808	$ (5,297)
Amortization of Intangible Assets	(6,100)	(5,500)	(6,000)
Goodwill [Roll Forward]
Goodwill	135,844	131,879	130,250
Goodwill acquired	106	1,815
Foreign exchange	3,867	134
Goodwill, Other Increase (Decrease)	8	320
Gross Carrying Amount	67,127	59,256
North America
Carrying amount of goodwill by reportable segment
Increase (Decrease) in Other Current Assets	161
Goodwill [Roll Forward]
Goodwill	96,311	96,244	96,435
Goodwill acquired	0	0
Foreign exchange	67	129
Goodwill, Other Increase (Decrease)	0	320
Gross Carrying Amount	40,786	33,756
Europe
Goodwill [Roll Forward]
Goodwill	38,059	34,300	32,471
Goodwill acquired	106	1,815
Foreign exchange	3,661	14
Goodwill, Other Increase (Decrease)	8	0
Gross Carrying Amount	26,341	25,500
Asia/Pacific
Goodwill [Roll Forward]
Goodwill	1,474	1,335	1,344
Goodwill acquired	0	0
Foreign exchange	139	(9)
Goodwill, Other Increase (Decrease)	0	0
Patents
Carrying amount of goodwill by reportable segment
Amortization of Intangible Assets	(373)	(150)
Goodwill [Roll Forward]
Gross Carrying Amount	4,699	4,659	2,109
Finite-lived Intangible Assets Acquired	40	2,550
Noncompete Agreements Trademarks and Other
Carrying amount of goodwill by reportable segment
Amortization of Intangible Assets	(2,195)	(1,910)
Reclassifications		(481)
Goodwill [Roll Forward]
Gross Carrying Amount	21,582	14,703	12,225
Finite-lived Intangible Assets Acquired		2,081
Noncompete Agreements Trademarks and Other \| North America
Carrying amount of goodwill by reportable segment
Reclassifications	481
Unpatented Technology
Carrying amount of goodwill by reportable segment
Amortization of Intangible Assets	(2,131)	(2,017)
Goodwill [Roll Forward]
Gross Carrying Amount	22,104	21,616	20,662
Finite-lived Intangible Assets Acquired		788
Customer Relationships
Carrying amount of goodwill by reportable segment
Amortization of Intangible Assets	(1,443)	(1,433)
Goodwill [Roll Forward]
Gross Carrying Amount	18,123	17,660	$ 17,563
Finite-lived Intangible Assets Acquired	$ 290	$ 124

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) in current assets classified as other.

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