Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018
Current Assets:
Cash and cash equivalents	$ 347,943	$ 284,355
Short-term investments	52,960	41,461
Accounts receivable, net of allowance of $9,927 and $6,217, respectively	495,602	565,202
Inventories of materials and supplies, net	149,653	158,134
Prepaid expenses and other	68,928	66,398
Total current assets	1,115,086	1,115,550
Investments	31,991	98,696
Property, plant and equipment, net	4,502,084	4,857,382
Other Noncurrent Assets:
Goodwill	82,786	64,777
Intangible assets, net	86,716	73,207
Other assets	20,852	5,255
Total other noncurrent assets	190,354	143,239
Total assets	5,839,515	6,214,867
Current Liabilities:
Accounts payable	123,146	132,664
Accrued liabilities	287,092	244,504
Total current liabilities	410,238	377,168
Noncurrent Liabilities:
Long-term debt, net	479,356	493,968
Deferred income taxes	806,611	853,136
Other	115,746	93,606
Noncurrent liabilities - discontinued operations	15,341	14,254
Total noncurrent liabilities	1,417,054	1,454,964
Commitments and Contingencies (Note 16)
Shareholders' Equity:
Common stock, $.10 par value, 160,000,000 shares authorized, 112,080,262 and 112,008,961 shares issued as of September 30, 2019 and 2018, respectively, and 108,437,904 and 108,993,718 shares outstanding as of September 30, 2019 and 2018, respectively	11,208	11,201
Preferred stock, no par value, 1,000,000 shares authorized, no shares issued	0	0
Additional paid-in capital	510,305	500,393
Retained earnings	3,714,307	4,027,779
Accumulated other comprehensive income (loss)	(28,635)	16,550
Treasury stock, at cost, 3,642,358 shares and 3,015,243 shares as of September 30, 2019 and 2018, respectively	(194,962)	(173,188)
Total shareholders’ equity	4,012,223	4,382,735
Total liabilities and shareholders' equity	$ 5,839,515	$ 6,214,867