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Goodwill - Changes in Carrying Amount of Goodwill (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($)
Goodwill [Roll Forward]
Balance at December 31, 2020	$ 206,008
Goodwill acquired during the period	280
Adjustments to preliminary purchase price allocations	0
Foreign currency translation	(631)
Balance at September 30, 2021	205,657
Services
Goodwill [Roll Forward]
Balance at December 31, 2020	190,112
Goodwill acquired during the period	280
Adjustments to preliminary purchase price allocations	0
Foreign currency translation	189
Balance at September 30, 2021	190,581
International
Goodwill [Roll Forward]
Balance at December 31, 2020	15,896
Goodwill acquired during the period	0
Adjustments to preliminary purchase price allocations	0
Foreign currency translation	(820)
Balance at September 30, 2021	15,076
Products and Systems
Goodwill [Roll Forward]
Balance at December 31, 2020	0
Goodwill acquired during the period	0
Adjustments to preliminary purchase price allocations	0
Foreign currency translation	0
Balance at September 30, 2021	$ 0

X

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
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-Section 55
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X

- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

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.

+ References

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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