Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 107,068	$ 411,848
Short-term investments	241,821	28,883
Accounts receivable, net	40,130	31,100
Inventory, net	31,486	22,959
Prepaid expenses and other	7,115	4,190
Total current assets	427,620	498,980
Property and equipment, net	27,043	20,828
Operating lease right-of-use assets	19,226	21,492
Other assets	5,592	2,895
Total assets	479,481	544,195
Current liabilities:
Accounts payable	14,283	5,313
Accrued liabilities	6,765	4,970
Accrued compensation and other employee benefits	17,466	15,262
Customer deposits	1,278	1,631
Deferred revenue and other liabilities, current portion	7,474	5,610
Operating lease liabilities, current portion	4,889	4,313
Total current liabilities	52,155	37,099
Deferred revenue and other liabilities, net of current portion	3,527	1,843
Long-term debt, net	225,144	172,703
Operating lease liabilities, net of current portion	21,693	25,602
Total liabilities	302,519	237,247
Commitments and contingencies (Note 16)
Stockholders’ equity
Preferred stock, $0.0001 par value, 15,000 shares authorized; none issued	0	0
Common stock, $0.0001 par value, 150,000 shares authorized; 45,729 and 44,441 shares issued and outstanding at December 31, 2021 and 2020, respectively	5	4
Additional paid-in-capital	827,028	848,891
Accumulated other comprehensive income (loss)	(318)	83
Accumulated deficit	(649,753)	(542,030)
Total stockholders’ equity	176,962	306,948
Total liabilities and stockholders’ equity	$ 479,481	$ 544,195
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	15,000,000	15,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, shares outstanding (in shares)	45,729,000	44,441,000
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, shares issued (in shares)	45,729,000	44,441,000