Details of Selected Financial Statement Captions - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Balance Sheet Related Disclosures [Abstract]
Interest	$ 249,066	$ 234,297	$ 207,555
Income taxes	14,968	15,760	8,199
Capital expenditures included in current liabilities	186,912	217,868	184,786
Interest paid, net of amount capitalized	$ 117,900	$ 98,400	$ 81,900

No definition available.

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Future cash outflow to pay for purchases of fixed assets that have occurred.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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