GOODWILL AND INTANGIBLE ASSETS - Amortization of intangible assets (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Finite-Lived intangible assets
Amortization	$ 30,888	$ 1,768
Estimated amortization expense for intangible assets for each of the next five fiscal years is expected to be as follows
2023	35,121
2024	35,074
2025	35,065
2026	34,861
2027	34,433
Thereafter	171,332
Totals	$ 345,886	24,233
Weighted Average
Estimated amortization expense for intangible assets for each of the next five fiscal years is expected to be as follows
RUL (in years)	10 years 3 months 18 days
Customer relationships
Estimated amortization expense for intangible assets for each of the next five fiscal years is expected to be as follows
2023	$ 28,039
2024	28,039
2025	28,039
2026	27,977
2027	27,792
Thereafter	152,021
Totals	$ 291,906	21,197
Customer relationships \| Weighted Average
Estimated amortization expense for intangible assets for each of the next five fiscal years is expected to be as follows
RUL (in years)	9 years 1 month 6 days
Intellectual property
Estimated amortization expense for intangible assets for each of the next five fiscal years is expected to be as follows
2023	$ 6,518
2024	6,517
2025	6,517
2026	6,517
2027	6,517
Thereafter	18,643
Totals	$ 51,230	3
Intellectual property \| Weighted Average
Estimated amortization expense for intangible assets for each of the next five fiscal years is expected to be as follows
RUL (in years)	1 year 2 months 12 days
Non-compete agreements
Estimated amortization expense for intangible assets for each of the next five fiscal years is expected to be as follows
2023	$ 455
2024	409
2025	400
2026	258
2027	15
Totals	$ 1,538	1,703
Non-compete agreements \| Weighted Average
Estimated amortization expense for intangible assets for each of the next five fiscal years is expected to be as follows
RUL (in years)	0 years
Other
Estimated amortization expense for intangible assets for each of the next five fiscal years is expected to be as follows
2023	$ 109
2024	109
2025	109
2026	109
2027	109
Thereafter	668
Totals	$ 1,212	$ 1,330
Other \| Weighted Average
Estimated amortization expense for intangible assets for each of the next five fiscal years is expected to be as follows
RUL (in years)	0 years

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of amortization for asset, excluding financial asset and goodwill, lacking physical substance with finite life expected to be recognized after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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