Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 35,703	$ 12,524
Deferred equity issuance costs		578
Investments	5,063	4,997
Prepaid expenses and other current assets	2,099	1,096
Total current assets	42,865	19,195
Property, plant and equipment, net	73,226	56,233
Other assets		349
Total assets	116,091	75,777
Current liabilities
Accounts payable	726	1,167
Share-based compensation liability	1,815
Accrued liabilities and other current liabilities	5,856	3,767
Total current liabilities	8,397	4,934
Non-current compensation liabilities	2,015	2,745
Non-current share-based compensation liability	2,587
Total liabilities	12,999	7,679
Commitments and contingencies (Note 12)
Stockholders’ equity
Preferred stock, $0.0001 par value, 1.0 million shares authorized, none issued
Common stock	11	10
Additional paid-in-capital	158,738	88,406
Accumulated deficit	(55,617)	(20,291)
Accumulated other comprehensive loss	(40)	(27)
Total stockholders’ equity	103,092	68,098
Total liabilities and stockholders’ equity	$ 116,091	$ 75,777