Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Sep. 30, 2020
Current Assets:
Cash and cash equivalents	$ 373,980	$ 487,884
Short-term investments	149,822	89,335
Accounts receivable, net of allowance of $1,618 and $1,820, respectively	233,623	192,623
Inventories of materials and supplies, net	99,353	104,180
Prepaid expenses and other, net	95,946	89,305
Total current assets	952,724	963,327
Investments	34,018	31,585
Property, plant and equipment, net	3,552,107	3,646,341
Other Noncurrent Assets:
Goodwill	45,653	45,653
Intangible assets, net	79,226	81,027
Operating lease right-of-use asset	42,920	44,583
Other assets, net	20,105	17,105
Total other noncurrent assets	187,904	188,368
Total assets	4,726,753	4,829,621
Current Liabilities:
Accounts payable	46,617	36,468
Dividends payable	27,378	27,226
Accrued liabilities	154,266	155,442
Total current liabilities	228,261	219,136
Noncurrent Liabilities:
Long-term debt, net	481,187	480,727
Deferred income taxes	635,443	650,675
Other	151,070	147,180
Noncurrent liabilities - discontinued operations	5,874	13,389
Total noncurrent liabilities	1,273,574	1,291,971
Commitments and Contingencies (Note 14)
Shareholders' Equity:
Common stock, $.10 par value, 160,000,000 shares authorized, 112,222,865 and 112,151,563 shares issued as of December 31, 2020 and September 30, 2020, respectively, and 107,854,368 and 107,488,242 shares outstanding as of December 31, 2020 and September 30, 2020, respectively	11,222	11,215
Preferred stock, no par value, 1,000,000 shares authorized, no shares issued	0	0
Additional paid-in capital	511,956	521,628
Retained earnings	2,911,006	3,010,012
Accumulated other comprehensive loss	(25,731)	(26,188)
Treasury stock, at cost, 4,368,497 shares and 4,663,321 shares as of December 31, 2020 and September 30, 2020, respectively	(183,535)	(198,153)
Total shareholders’ equity	3,224,918	3,318,514
Total liabilities and shareholders' equity	$ 4,726,753	$ 4,829,621