Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 39,181	$ 24,990
Short-term investments	51,508	0
Accounts receivable, net of allowances of $45 and $22 at December 31, 2019 and 2018, respectively	8,601	6,382
Inventories	10,322	5,744
Prepaid expenses and other current assets	2,878	1,408
Total current assets	112,490	38,524
Long-term investments	18,224	0
Property and equipment, net	2,734	2,880
Restricted cash	310	310
Other non-current assets	3,644	1,029
Total assets	137,402	42,743
Current liabilities:
Accounts payable	1,898	1,252
Accrued liabilities	15,034	9,448
Total current liabilities	16,932	10,700
Long-term debt	44,879	44,201
Redeemable convertible preferred stock warrant liability	0	16,091
Other liabilities	3,700	1,069
Total liabilities	65,511	72,061
Commitments and contingencies (Note 7)
Redeemable convertible preferred stock issuable in series, $0.001 par value
Liquidation preference: $121,144 at December 31, 2017 and 2018	0	105,235
Preferred stock, $0.001 par value
Shares authorized: 5,000,000 and none at December 31, 2019 and 2018, respectively	0	0
Shares issued and outstanding: 31,255,267 and 1,135,310 at December 31, 2019 and 2018, respectively	31	1
Additional paid-in capital	263,384	4,557
Accumulated other comprehensive income	2	0
Accumulated deficit	(191,526)	(139,111)
Total stockholders’ equity (deficit)	71,891	(134,553)
Total liabilities and stockholders’ equity (deficit)	$ 137,402	$ 42,743