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Goodwill - Changes in Carrying Amount of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Changes in the carrying amount of goodwill
Balance at the beginning of the period	$ 206,008	$ 282,410
Impairment charges	0	(77,089)
Adjustments to preliminary purchase price allocations	280	200
Foreign currency translation	(849)	487
Balance at the end of the period	205,439	206,008
Services
Changes in the carrying amount of goodwill
Balance at the beginning of the period	190,112	247,215
Impairment charges	0	(57,227)
Adjustments to preliminary purchase price allocations	280	200
Foreign currency translation	264	(76)
Balance at the end of the period	190,656	190,112
International
Changes in the carrying amount of goodwill
Balance at the beginning of the period	15,896	35,195
Impairment charges	0	(19,862)
Adjustments to preliminary purchase price allocations	0	0
Foreign currency translation	(1,113)	563
Balance at the end of the period	14,783	15,896
Products and Systems
Changes in the carrying amount of goodwill
Balance at the beginning of the period	0	0
Impairment charges	0	0
Adjustments to preliminary purchase price allocations	0	0
Foreign currency translation	0	0
Balance at the end of the period	$ 0	$ 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

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-Publisher FASB
-Name Accounting Standards Codification
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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 loss from the write-down 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

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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

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

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