CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2018	Sep. 30, 2018
Current assets:
Cash and cash equivalents	$ 6,098	$ 5,965
Certificates of deposit	0	741
Accounts and other receivables, net of allowance for doubtful accounts of: $40,000 at December 31, 2018; $42,000 at September 30, 2018	1,465	1,965
Income taxes receivable	1,503	2,461
Other current assets	1,765	950
Total current assets	10,831	12,082
Income taxes receivable, net of current portion	460	429
Asset for retirement benefits	865	848
Investments	1,177	1,608
Property and equipment	70,241	73,010
Accumulated depletion, depreciation, and amortization	(56,896)	(56,599)
Property and equipment, net	13,345	16,411
Total assets	26,678	31,378
Current liabilities:
Accounts payable	1,604	1,191
Accrued capital expenditures	156	232
Accrued compensation	495	568
Accrued operating and other expenses	957	1,140
Current portion of asset retirement obligation	554	444
Other current liabilities	452	54
Total current liabilities	4,218	3,629
Deferred rent	129	107
Liability for retirement benefits	4,463	4,410
Asset retirement obligation	6,446	6,678
Deferred income tax liabilities	239	315
Total liabilities	15,495	15,139
Commitments and contingencies
Equity:
Common stock, par value $0.50 per share; authorized, 20,000,000 shares: 8,445,060 issued at December 31, 2018 and September 30, 2018	4,223	4,223
Additional paid-in capital	1,350	1,350
Retained earnings	8,673	13,253
Accumulated other comprehensive loss, net	(910)	(514)
Treasury stock, at cost: 167,900 shares at December 31, 2018 and September 30, 2018	(2,286)	(2,286)
Total stockholders' equity	11,050	16,026
Non-controlling interests	133	213
Total equity	11,183	16,239
Total liabilities and equity	$ 26,678	$ 31,378