Goodwill and Intangible Assets - Changes in Net Carrying Amount of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Goodwill [Roll Forward]
Balance at beginning of period	$ 3,493	$ 12,020
Goodwill impairment adjustment	0	(8,294)
Currency translation	0	(233)
Balance at end of period	$ 3,493	$ 3,493

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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- 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.

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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.

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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.

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