Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 34,281	$ 46,407
Restricted cash, current portion	399	4,597
Short-term investments	93,805	107,461
Accounts receivable, net of allowance of $1,794 in 2019 and $1,788 in 2018	60,293	62,223
Inventory	13,748	13,633
Prepaid expenses and other current assets	5,555	6,197
Total current assets	208,081	240,518
Property and equipment, net	23,302	24,336
Operating lease right-of-use assets	27,260
Other assets	2,802	3,317
Total assets	261,445	268,171
Current liabilities:
Accounts payable	8,917	14,587
Accrued compensation	10,818	12,668
Other accrued liabilities	37,839	32,442
Deferred revenue, current portion	4,928	4,131
Short-term debt financing	50,154	50,153
Total current liabilities	112,656	113,981
Long-term debt financing	73,431	73,357
Deferred rent, net of current portion		8,613
Deferred revenue, long-term portion	39,698	40,058
Operating lease liabilities, long-term portion	30,674
Total liabilities	256,459	236,009
Commitments and contingencies (Note 8)
Stockholders' equity:
Common stock, $0.0001 par value: 750,000 shares authorized at both March 31, 2019 and December 31, 2018, respectively; 63,340 and 62,083 shares issued and outstanding at March 31, 2019 and December 31, 2018, respectively	7	7
Additional paid in capital	613,680	607,236
Accumulated deficit	(608,435)	(574,529)
Accumulated other comprehensive loss	(266)	(552)
Total stockholders' equity	4,986	32,162
Total liabilities and stockholders' equity	$ 261,445	$ 268,171