CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 33,679	$ 34,986
Short-term investments	99,426	50,732
Accounts receivable	18,165	16,882
Inventories	21,684	19,490
Prepaid and other current assets	5,365	6,018
Total current assets	178,319	128,108
Non-current assets:
Property and equipment, net	14,654	14,898
Goodwill	1,316	1,316
Operating lease right-of-use assets	14,080	14,122
Intangible assets, net	82	132
Restricted cash	2,439	2,435
Other assets	4,473	4,524
Total assets	215,363	165,535
Current liabilities:
Accounts payable	20,185	22,185
Accrued liabilities	17,198	20,951
Debt – current	4,813	5,017
Operating lease liabilities – current	1,751	1,613
Deferred product revenue – current	1,142	570
Total current liabilities	45,089	50,336
Non-current liabilities:
Debt – non-current	39,458	39,414
Operating lease liabilities – non-current	18,005	18,406
Other non-current liabilities	403	327
Total liabilities	102,955	108,483
Commitments and contingencies
Stockholders' equity:
Common stock	164	144
Additional paid-in capital	978,944	906,905
Accumulated other comprehensive (loss) income	(123)	114
Accumulated deficit	(866,577)	(850,111)
Total stockholders' equity	112,408	57,052
Total liabilities and stockholders' equity	$ 215,363	$ 165,535