Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets
Cash and cash equivalents	$ 49,033	$ 80,367
Marketable securities	30,020	15,107
Restricted cash	250	125
Accounts receivable, net	24,739	29,438
Inventories	12,732	11,020
Other receivables	3,520	3,679
Prepaid and other current assets	12,988	12,364
Total current assets	133,282	152,100
Long-term restricted cash	125	125
Fixed assets, net	762	794
Goodwill	829	829
Right-of-use assets	1,536	1,757
Long-term inventories	32,955	27,767
Other long-term assets	668	497
Total assets	170,157	183,869
Current liabilities
Accounts payable	4,697	5,394
Accrued expenses	22,133	23,446
Other current liabilities	2,007	2,457
Total current liabilities	28,837	31,297
Long-term debt	255,949	254,428
Long-term lease liabilities	1,063	1,308
Accrued long-term compensation	21,893	21,846
Other liabilities	2,717	2,777
Total liabilities	310,459	311,656
Stockholders’ deficit
Undesignated preferred stock: $0.001 par value, 5,000,000 shares authorized; no shares issued and outstanding	0	0
Common stock, $0.001 par value; 200,000,000 shares authorized; 53,023,350 shares issued and outstanding as of March 31, 2022; and 200,000,000 shares authorized; 51,711,809 shares issued and outstanding as of December 31, 2021	53	52
Additional paid-in capital	744,618	739,053
Accumulated other comprehensive income	(180)	(9)
Accumulated deficit	(884,793)	(866,883)
Total stockholders’ deficit	(140,302)	(127,787)
Total liabilities and stockholders’ deficit	$ 170,157	$ 183,869