CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 63,543	$ 123,903
Short-term investments	101,724	69,443
Accounts receivable, net	38,533	35,449
Inventory	31,561	21,958
Prepaid expenses and other current assets	7,195	5,049
Total current assets	242,556	255,802
Long-term investments	28,144	14,225
Property and equipment, net	29,133	27,500
Operating lease right-of-use assets	10,863	11,667
Other non-current assets	2,365	2,462
Goodwill	3,881	3,881
Total assets	316,942	315,537
Current liabilities:
Accounts payable	9,103	11,732
Accrued compensation and employee related benefits	4,590	6,365
Accrued and other current liabilities	3,878	2,481
Current portion of operating lease liabilities	3,967	4,143
Restructuring liabilities	554	591
Current portion of long-term debt	9,643	9,633
Current portion of deferred revenue	907	558
Total current liabilities	32,642	35,503
Long-term debt, net of current portion	279,054	278,661
Operating lease liabilities, net of current portion	11,102	11,934
Other long-term liabilities	113	279
Deferred revenue, net of current portion	320	236
Total liabilities	323,231	326,613
Commitments and contingencies (Note 5)
Stockholders' equity:
Preferred stock, $0.001 par value — 5,000 shares authorized, no shares issued and outstanding at March 31, 2022 and December 31, 2021
Common stock, $0.001 par value — 495,000 shares authorized, 25,220 and 24,737 shares issued and outstanding at March 31, 2022 and December 31, 2021, respectively	25	25
Additional paid-in capital	367,347	351,422
Accumulated other comprehensive (loss) income	(716)	(39)
Accumulated deficit	(372,945)	(362,484)
Total stockholders' equity	(6,289)	(11,076)
Total liabilities and stockholders' equity	$ 316,942	$ 315,537