UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2024	Sep. 30, 2024
Current Assets:
Cash and cash equivalents	$ 391,179	$ 217,341
Restricted cash	73,216	68,902
Short-term investments	135,317	292,919
Accounts receivable, net of allowance of $2,720 and $2,977, respectively	426,933	418,604
Inventories of materials and supplies, net	127,288	117,884
Prepaid expenses and other, net	70,898	76,419
Total current assets	1,224,831	1,192,069
Investments, net	101,652	100,567
Property, plant and equipment, net	3,009,360	3,016,277
Other Noncurrent Assets:
Goodwill	45,653	45,653
Intangible assets, net	52,547	54,147
Operating lease right-of-use assets	67,510	67,076
Restricted cash	1,242,124	1,242,417
Other assets, net	72,944	63,692
Total other noncurrent assets	1,480,778	1,472,985
Total assets	5,816,621	5,781,898
Current Liabilities:
Accounts payable	148,752	135,084
Dividends payable	25,154	25,024
Accrued liabilities	261,807	286,841
Total current liabilities	435,713	446,949
Noncurrent Liabilities:
Long-term debt, net	1,781,674	1,782,182
Deferred income taxes	485,682	495,481
Other	166,771	140,134
Total noncurrent liabilities	2,434,127	2,417,797
Commitments and Contingencies (Note 12)
Shareholders' Equity:
Common stock, $0.10 par value, 160,000,000 shares authorized, 112,222,865 shares issued as of December 31, 2024 and September 30, 2024, and 99,186,843 and 98,755,412 shares outstanding as of December 31, 2024 and September 30, 2024, respectively	11,222	11,222
Preferred stock, no par value, 1,000,000 shares authorized, no shares issued	0	0
Additional paid-in capital	501,516	518,083
Retained earnings	2,913,211	2,883,590
Accumulated other comprehensive loss	(5,987)	(6,350)
Treasury stock, at cost, 13,036,022 shares and 13,467,453 shares as of December 31, 2024 and September 30, 2024, respectively	(473,181)	(489,393)
Total shareholders’ equity	2,946,781	2,917,152
Total liabilities and shareholders' equity	$ 5,816,621	$ 5,781,898

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_AccountsPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).