CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($)
$ in Thousands
Sep. 30, 2021
Dec. 31, 2020
Current assets:    
Cash and cash equivalents $ 264,017 $ 91,165
Investments 0 85,122
Prepaid expenses and other current assets 6,451 5,224
Total current assets 270,468 181,511
Operating lease, right-of-use-asset 36,296 40,447
Property, plant and equipment, net 52,727 53,952
Restricted cash 1,573 1,573
Other assets   311
Total assets 361,064 277,794
Current liabilities:    
Accounts payable 8,492 5,478
Accrued expenses and other current liabilities 13,622 13,417
Operating lease liabilities 8,820 8,945
Total current liabilities 30,934 27,840
Long-term debt, net of discount 75,929 74,944
Other long-term liabilities 586 688
Operating lease liabilities, net of current portion 29,410 32,762
Total liabilities 136,859 136,234
Commitments and contingencies (see Note 9)
Stockholders' equity:    
Preferred stock, $0.001 par value; 10,000,000 shares authorized at September 30, 2021 and December 31, 2020; no shares issued or outstanding at September 30, 2021 and December 31, 2020
September 30, 2021 and December 31, 2020; 89,862,482 and 81,053,651 shares issued and outstanding at September 30, 2021 and December 31, 2020, respectively 90 81
Additional paid-in capital 846,112 621,946
Accumulated other comprehensive income   4
Accumulated deficit (621,997) (480,471)
Total stockholders' equity 224,205 141,560
Total liabilities and stockholders' equity $ 361,064 $ 277,794