Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2016	Sep. 30, 2015
Current assets:
Cash and cash equivalents	$ 105,046	$ 111,885
Restricted cash	1,219	375
Accounts receivable, net of allowance of $53 and $462, respectively	21,630	17,319
Inventory	18,976	17,130
Prepaid expenses and other current assets	3,778	4,976
Total current assets	150,649	151,685
Property, plant, and equipment, net	11,001	8,925
Non-current inventory	4,270	0
Other non-current assets, net of allowance of $0 and $3,561, respectively	319	297
Total assets	166,239	160,907
Current liabilities:
Accounts payable	9,581	7,189
Deferred gain associated with sale of assets	0	3,400
Accrued expenses and other current liabilities	11,205	13,102
Total current liabilities	20,786	23,691
Asset retirement obligations	1,589	1,774
Other long-term liabilities	61	0
Total liabilities	22,436	25,465
Commitments and contingencies (Note 11)
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; 33,041 shares issued and 26,131 shares outstanding as of June 30, 2016; 32,586 shares issued and 25,676 shares outstanding as of September 30, 2015	764,324	762,003
Treasury stock at cost; 6,910 shares at June 30, 2016 and September 30, 2015	(47,721)	(47,721)
Accumulated other comprehensive income	617	847
Accumulated deficit	(573,417)	(579,687)
Total shareholders’ equity	143,803	135,442
Total liabilities and shareholders’ equity	$ 166,239	$ 160,907