GOODWILL AND INTANGIBLE ASSETS - Summary of Changes in Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Goodwill [Roll Forward]
Balance	$ 64,777	$ 51,705
Additions	18,009	17,791
Impairment		(4,719)
Balance	$ 82,786	$ 64,777

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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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.

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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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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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