Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 58,975	$ 90,471
Short-term marketable securities	24,334	325
Accounts receivable—net of allowance of $269 and $225 at September 30, 2016 and December 31, 2015, respectively	23,087	9,523
Prepaid expenses	4,572	5,010
Other current assets	472	614
Total current assets	111,440	105,943
Property and equipment, net	13,805	11,732
Goodwill	989	989
Intangible assets, net	471	444
Noncurrent prepaid expenses	622	749
Other assets	1,027	1,203
Total assets	128,354	121,060
Current liabilities:
Accounts payable	5,977	3,912
Accrued liabilities	10,873	8,852
Deferred rent	708	541
Deferred revenue	81,563	49,384
Total current liabilities	99,121	62,689
Deferred revenue, net of current portion	3,222	2,941
Deferred rent, net of current portion	8,532	9,078
Warrant liability	35	331
Other long-term liabilities	36	402
Total liabilities	110,946	75,441
Stockholders’ equity:
Common stock	3	4
Treasury stock		(1)
Additional paid-in capital	200,961	188,517
Accumulated other comprehensive loss	(9)
Accumulated deficit	(183,547)	(142,901)
Total stockholders’ equity	17,408	45,619
Total liabilities and stockholders’ equity	$ 128,354	$ 121,060