Financial Instruments and Fair Value Measurements (Financial Assets and Liabilities that are Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Sep. 30, 2025
Financial assets:
Total financial assets	$ 59,746	$ 68,102
Financial liabilities:
Total financial liabilities	18,376	27,406
Cross Currency Interest Rate Swaps [Member]
Financial liabilities:
Cross-currency interest rate swaps	18,376	27,406
Level 1 [Member]
Financial assets:
Total financial assets	59,746	68,102
Level 2 [Member]
Financial liabilities:
Total financial liabilities	18,376	27,406
Level 2 [Member] \| Cross Currency Interest Rate Swaps [Member]
Financial liabilities:
Cross-currency interest rate swaps	18,376	27,406
Investments in Banks and Financial Institutions [Member]
Financial assets:
Investments in money markets and depository accounts	16,220	30,256
Investments in Banks and Financial Institutions [Member] \| Level 1 [Member]
Financial assets:
Investments in money markets and depository accounts	16,220	30,256
Equity Securities [Member]
Financial assets:
Equity securities	43,526	37,846
Equity Securities [Member] \| Level 1 [Member]
Financial assets:
Equity securities	$ 43,526	$ 37,846

Fair value portion of asset recognized for present right to economic benefit.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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