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FAIR VALUE MEASUREMENT OF FINANCIAL INSTRUMENTS - Schedule of Reconciliation of Changes in Fair Value of Financial Assets and Liabilities Classified as Level 3 (Details) - Level 3 - Equity Securities Without Readily Determinable Fair Value - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2026 | Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025 | Sep. 30, 2025
Reconciliation of changes in the fair value of our financial assets |  |  |  |  |
Assets at beginning of period | $ 17,547 | $ 45,519 | $ 20,861 | $ 30,090 | $ 30,090
Purchases | 1,201 | 594 | 2,239 | 1,528 |
Disposals | 0 | (27,117) | 0 | (27,117) |
Sales | 0 | 0 | (124) | 0 |
Transfer in | 0 | 320 | 0 | 320 |
Total gain (loss): |  |  |  |  |
Included in earnings | 0 | 624 | (4,228) | 15,119 |
Assets at end of period | $ 18,748 | $ 19,940 | $ 18,748 | $ 19,940 | $ 20,861

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- Definition 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. + 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 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 102 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-102 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 + Details
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