Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 81,310	$ 99,240
Trade accounts receivable, net of allowance for doubtful accounts of $720 and $691 in 2019 and 2018, respectively	10,245	12,324
Inventories	8,087	6,627
Prepaid expenses and other current assets	1,093	1,117
Total current assets	100,735	119,308
Property, plant and equipment, net	5,305	5,213
Goodwill	33,491	33,491
Other long-term assets	1,285
Total assets	140,816	158,012
Current liabilities:
Accounts payable	6,525	7,950
Accrued liabilities	5,831	5,736
Accrued compensation	2,903	6,858
Total current liabilities	15,259	20,544
Other long-term liabilities	1,629	490
Long-term debt, net	44,375	44,082
Total liabilities	61,263	65,116
Commitments and contingencies (Note 8)
Stockholders’ equity:
Common stock, $0.001 par value, 100,000,000 shares authorized; 17,792,244 and 17,689,928 shares issued and outstanding in 2019 and 2018, respectively	18	18
Additional paid-in capital	220,271	218,844
Accumulated other comprehensive gain	1	1
Accumulated deficit	(140,737)	(125,967)
Total stockholders’ equity	79,553	92,896
Total liabilities and stockholders’ equity	$ 140,816	$ 158,012