Unaudited Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2022	Sep. 30, 2021
Current Assets:
Cash and cash equivalents	$ 202,206	$ 917,534
Short-term investments	148,377	198,700
Accounts receivable, net of allowance of $2,490 and $2,068, respectively	329,572	228,894
Inventories of materials and supplies, net	83,588	84,057
Prepaid expenses and other, net	97,380	85,928
Assets held-for-sale	57,373	71,453
Total current assets	918,496	1,586,566
Investments	219,295	135,444
Property, plant and equipment, net	3,022,335	3,127,287
Other Noncurrent Assets:
Goodwill	45,653	45,653
Intangible assets, net	70,246	73,838
Operating lease right-of-use assets	45,325	49,187
Other assets, net	13,000	16,153
Total other noncurrent assets	174,224	184,831
Total assets	4,334,350	5,034,128
Current Liabilities:
Accounts payable	105,123	71,996
Dividends payable	26,697	27,332
Current portion of long-term debt, net	0	483,486
Accrued liabilities	245,778	283,492
Total current liabilities	377,598	866,306
Noncurrent Liabilities:
Long-term debt, net	541,969	541,997
Deferred income taxes	552,263	563,437
Other	125,754	147,757
Noncurrent liabilities - discontinued operations	2,356	2,013
Total noncurrent liabilities	1,222,342	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 March 31, 2022 and September 30, 2021, and 105,285,460 and 107,898,859 shares outstanding as of March 31, 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	514,771	529,903
Retained earnings	2,463,665	2,573,375
Accumulated other comprehensive loss	(19,456)	(20,244)
Treasury stock, at cost, 6,937,405 shares and 4,324,006 shares as of March 31, 2022 and September 30, 2021, respectively	(235,792)	(181,638)
Total shareholders’ equity	2,734,410	2,912,618
Total liabilities and shareholders' equity	$ 4,334,350	$ 5,034,128