Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2016	Sep. 30, 2015
Current assets:
Cash and cash equivalents	$ 63,905	$ 111,885
Restricted cash	965	375
Accounts receivable, net of allowance of $36 and $462, respectively	18,432	17,319
Inventory	24,150	17,130
Prepaid expenses and other current assets	3,764	4,976
Total current assets	111,216	151,685
Property, plant, and equipment, net	12,213	8,925
Non-current inventory	3,531	0
Other non-current assets, net of allowance of $0 and $3,561, respectively	251	297
Total assets	127,211	160,907
Current liabilities:
Accounts payable	10,575	7,189
Deferred gain associated with sale of assets	0	3,400
Accrued expenses and other current liabilities	7,684	13,102
Total current liabilities	18,259	23,691
Asset retirement obligations	1,573	1,774
Other long-term liabilities	62	0
Total liabilities	19,894	25,465
Commitments and contingencies (Note 12)
Shareholders’ equity:
Preferred stock, $0.0001 par value, 5,882 shares authorized; none issued or outstanding	0	0
Common stock, no par value, 50,000 shares authorized; 33,154 shares issued and 26,244 shares outstanding as of September 30, 2016; 32,586 shares issued and 25,676 shares outstanding as of September 30, 2015	725,880	762,003
Treasury stock at cost; 6,910 shares at September 30, 2016 and 2015	(47,721)	(47,721)
Accumulated other comprehensive income	579	847
Accumulated deficit	(571,421)	(579,687)
Total shareholders’ equity	107,317	135,442
Total liabilities and shareholders’ equity	$ 127,211	$ 160,907