Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
CURRENT ASSETS:
Cash and cash equivalents	$ 337,143	$ 132,735
Short-term investments	49,326	0
Accounts receivable, net of allowance for doubtful accounts	49,513	57,572
Inventories, net	66,319	58,290
Prepaid expenses	7,751	9,778
Other current assets	3,092	3,590
Total Current Assets	513,144	261,965
Property, plant and equipment, net	826,152	800,586
Deposits on equipment	2,936	3,823
Operating lease right of use assets	4,808	5,165
Equity method investment	0	25,418
Long term investment in equity securities	24,438	0
Other assets	28,539	28,426
Total Assets	1,400,017	1,125,383
CURRENT LIABILITIES:
Accounts payable	26,391	55,088
Accrued expenses	27,805	33,016
Current operating lease liabilities	1,543	1,510
Total Current Liabilities	55,739	89,614
Convertible senior notes	391,567	0
Long term operating lease liabilities	3,804	4,200
Total Liabilities	451,110	93,814
STOCKHOLDERS' EQUITY:
Common stock — voting, $0.001 par value, 200,000 shares authorized, 48,123 issued and 48,109 outstanding on March 31, 2023, and 48,051 issued and 48,037 outstanding on December 31, 2022	48	48
Additional paid-in capital	1,267,642	1,325,524
Accumulated deficit	(319,903)	(295,117)
Accumulated other comprehensive income	1,376	1,370
Treasury stock, at cost — 14 shares on March 31, 2023 and on December 31, 2022	(256)	(256)
Total Stockholders' Equity	948,907	1,031,569
Total Liabilities and Stockholders' Equity	$ 1,400,017	$ 1,125,383