UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2022	Sep. 30, 2021
Current Assets:
Cash and cash equivalents	$ 188,663	$ 917,534
Short-term investments	144,331	198,700
Accounts receivable, net of allowance of $3,032 and $2,068, respectively	397,880	228,894
Inventories of materials and supplies, net	86,091	84,057
Prepaid expenses and other, net	103,589	85,928
Assets held-for-sale	25,604	71,453
Total current assets	946,158	1,586,566
Investments	213,956	135,444
Property, plant and equipment, net	2,987,107	3,127,287
Other Noncurrent Assets:
Goodwill	45,653	45,653
Intangible assets, net	68,950	73,838
Operating lease right-of-use assets	40,539	49,187
Other assets, net	20,247	16,153
Total other noncurrent assets	175,389	184,831
Total assets	4,322,610	5,034,128
Current Liabilities:
Accounts payable	119,972	71,996
Dividends payable	26,693	27,332
Current portion of long-term debt, net	0	483,486
Accrued liabilities	254,611	283,492
Total current liabilities	401,276	866,306
Noncurrent Liabilities:
Long-term debt, net	542,290	541,997
Deferred income taxes	527,545	563,437
Other	116,770	147,757
Noncurrent liabilities - discontinued operations	2,061	2,013
Total noncurrent liabilities	1,188,666	1,255,204
Commitments and contingencies (Note 13)
Shareholders' Equity:
Common stock, $.10 par value, 160,000,000 shares authorized, 112,222,865 shares issued as of both June 30, 2022 and September 30, 2021, and 105,290,017 and 107,898,859 shares outstanding as of June 30, 2022 and September 30, 2021, respectively	11,222	11,222
Preferred stock, no par value, 1,000,000 shares authorized, no shares issued	0	0
Additional paid-in capital	521,439	529,903
Retained earnings	2,454,726	2,573,375
Accumulated other comprehensive loss	(19,067)	(20,244)
Treasury stock, at cost, 6,932,848 shares and 4,324,006 shares as of June 30, 2022 and September 30, 2021, respectively	(235,652)	(181,638)
Total shareholders’ equity	2,732,668	2,912,618
Total liabilities and shareholders' equity	$ 4,322,610	$ 5,034,128