Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020
Current Assets:
Cash and cash equivalents	$ 917,534	$ 487,884
Short-term investments	198,700	89,335
Accounts receivable, net of allowance of $2,068 and $1,820, respectively	228,894	192,623
Inventories of materials and supplies, net	84,057	104,180
Prepaid expenses and other, net	85,928	89,305
Assets held-for-sale	71,453	0
Total current assets	1,586,566	963,327
Investments	135,444	31,585
Property, plant and equipment, net	3,127,287	3,646,341
Other Noncurrent Assets:
Goodwill	45,653	45,653
Intangible assets, net	73,838	81,027
Operating lease right-of-use asset	49,187	44,583
Other assets, net	16,153	17,105
Total other noncurrent assets	184,831	188,368
Total assets	5,034,128	4,829,621
Current Liabilities:
Accounts payable	71,996	36,468
Dividends payable	27,332	27,226
Current portion of long-term debt	483,486	0
Accrued liabilities	283,492	155,442
Total current liabilities	866,306	219,136
Noncurrent Liabilities:
Long-term debt, net	541,997	480,727
Deferred income taxes	563,437	650,675
Other	147,757	147,180
Noncurrent liabilities - discontinued operations	2,013	13,389
Total noncurrent liabilities	1,255,204	1,291,971
Commitments and Contingencies (Note 16)
Shareholders' Equity:
Common stock, $0.10 par value, 160,000,000 shares authorized, 112,222,865 and 112,151,563 shares issued as of September 30, 2021 and 2020, respectively, and 107,898,859 and 107,488,242 shares outstanding as of September 30, 2021 and 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	529,903	521,628
Retained earnings	2,573,375	3,010,012
Accumulated other comprehensive loss	(20,244)	(26,188)
Treasury stock, at cost, 4,324,006 shares and 4,663,321 shares as of September 30, 2021 and 2020, respectively	(181,638)	(198,153)
Total shareholders’ equity	2,912,618	3,318,514
Total liabilities and shareholders' equity	$ 5,034,128	$ 4,829,621

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).

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- 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).