Goodwill and Other Intangible Assets - Schedule of Changes in Carrying Amount of Goodwill (Detail) $ in Thousands	12 Months Ended
Sep. 30, 2018 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 10,455
Impairment losses	(10,423)
Foreign currency translation adjustment	(32)
Ending balance	$ 0

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.

+ 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.

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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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