Financial Instruments and Fair Value Measurements (Financial Assets that are Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Financial assets:
Total financial assets	$ 73,492	$ 98,573
Cross Currency Interest Rate Swaps [Member]
Financial assets:
Cross-currency interest rate swaps	9,582	38,168
Level 1 [Member]
Financial assets:
Total financial assets	63,910	60,405
Level 2 [Member]
Financial assets:
Total financial assets	9,582	38,168
Level 2 [Member] | Cross Currency Interest Rate Swaps [Member]
Financial assets:
Cross-currency interest rate swaps	9,582	38,168
Investments in Term Deposits with Foreign Banks [Member]
Financial assets:
Investments	38,705	37,605
Investments in Term Deposits with Foreign Banks [Member] | Level 1 [Member]
Financial assets:
Investments	38,705	37,605
Equity Securities [Member]
Financial assets:
Equity securities	25,205	22,800
Equity Securities [Member] | Level 1 [Member]
Financial assets:
Equity securities	$ 25,205	$ 22,800