Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 31,257	$ 7,257
Short-term marketable securities	250	6,975
Accounts receivable, net	4,672	10,915
Inventories	2,445	5,401
Prepaid expenses and other current assets	1,010	1,689
Total current assets	39,634	32,237
Property and equipment, net	5,103	4,608
Operating lease right-of-use assets	6,606	5,434
Other assets, net	1,081	1,267
Acquired intangible assets, net	1,207	2,704
Goodwill	18,407	18,407
Total assets	72,038	64,657
Current liabilities:
Accounts payable	995	818
Accrued liabilities and current portion of long-term liabilities	9,452	8,692
Current portion of income taxes payable	147	164
Total current liabilities	10,594	9,674
Long-term liabilities, net of current portion	1,007	982
Operating lease liabilities, net of current portion	5,088	4,212
Income taxes payable, net of current portion	2,479	2,260
Total liabilities	19,168	17,128
Commitments and contingencies (Note 10)
Shareholders' equity:
Preferred stock, $0.001 par value, 50,000,000 shares authorized, none issued	0	0
Common stock, $0.001 par value; 250,000,000 shares authorized, 51,078,942 and 38,434,488 shares issued and outstanding as of December 31, 2020 and 2019, respectively.	467,957	436,122
Accumulated other comprehensive income	47	12
Accumulated deficit	(415,134)	(388,605)
Total shareholders' equity	52,870	47,529
Total liabilities and shareholders' equity	$ 72,038	$ 64,657
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	50,000,000	50,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	250,000,000	250,000,000

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer), including liabilities for compensation costs, fringe benefits other than pension and postretirement obligations, rent, contractual rights and obligations, and statutory obligations.

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- Definition

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).