Goodwill and Intangible Assets - Changes in Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2019	Sep. 30, 2020
Goodwill [Roll Forward]
Balance at September 30, 2019	$ 32,636	$ 32,636
Other adjustments		806
Foreign currency effect on goodwill		2,227
Balance at September 30, 2020		$ 35,669
A2iA
Goodwill [Roll Forward]
Other adjustments	$ 800

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(10)(1))
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-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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Amount of increase (decrease), classified as other, of an asset representing the future economic benefits 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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