XML 131 R108.htm IDEA: XBRL DOCUMENT
v3.25.3

FAIR VALUE MEASUREMENTS - Changes in Allowance For Expected Credit Losses on Convertible Debt Instruments (Details) - Convertible debt investments - USD ($) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2025 | Sep. 30, 2024
Debt Securities, Available-for-Sale, Allowance for Credit Loss [Roll Forward] |  |
Balance at beginning of year | $ 1.9 | $ 101.3
Reductions for securities sold / exchanged | 0.0 | (99.4)
Balance at end of year | $ 1.9 | $ 1.9

X
- Definition Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (aaa) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479130/326-30-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-9 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-9 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLossRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of decrease in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from sale. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-9 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_ConvertibleDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |