FAIR VALUE MEASUREMENT OF FINANCIAL INSTRUMENTS - Reconciliation of Changes in Fair Value of Financial Assets and Liabilities Classified as Level 3 (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022
Reconciliation of changes in the fair value of our financial assets
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Selling, general and administrative	Selling, general and administrative
Reconciliation of changes in the fair value of our financial liabilities
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Selling, general and administrative	Selling, general and administrative
Level 3
Reconciliation of changes in the fair value of our financial assets
Assets at beginning of period	$ 23,745	$ 2,865
Purchases	4,487	15,177
Transfers in/(out)	0	3,000
Unrealized gain included in earnings	0	2,703
Assets at end of period	28,232	23,745
Reconciliation of changes in the fair value of our financial liabilities
Liabilities at beginning of period	4,022	2,996
Additions	500	1,500
Total gains or losses included in earnings	7,808	(224)
Settlements	(2,875)	(250)
Liabilities at end of period	9,455	4,022
Level 3 \| Galileo Technologies
Reconciliation of changes in the fair value of our financial assets
Assets at beginning of period	33,565	500
Purchases	2,122	36,065
Accrued interest	2,434	0
Transfers in/(out)	0	(3,000)
Reserves	(681)	0
Assets at end of period	$ 37,440	$ 33,565

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis Accrued Interest

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Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Reserves

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Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers In (Out)

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- Definition

Indicates line item in statement in which net income is reported that includes unrealized gain (loss) from asset measured at fair value using unobservable input (level 3) and still held.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

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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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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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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-SubTopic 10
-Topic 820
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Indicates line item in statement in which net income is reported that includes gain (loss) from liability measured at fair value using unobservable input (level 3).

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