CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 102,775	$ 93,677
Marketable securities	137,489	131,190
Accounts receivable, net of allowance for doubtful accounts of $919 and $1,269 as of June 30, 2017 and December 31, 2016, respectively	41,311	37,343
Prepaid expenses and other current assets	21,141	17,608
Total current assets	302,716	279,818
Marketable securities, noncurrent	68,502	75,168
Property and equipment, net	61,753	62,731
Goodwill and intangible assets, net	68,762	53,296
Other assets	7,909	4,272
Total assets	509,642	475,285
Current liabilities:
Accounts payable	8,161	4,555
Accrued liabilities	19,935	19,106
Accrued compensation and related benefits	21,982	20,281
Deferred revenue	141,345	123,276
Total current liabilities	191,423	167,218
Deferred revenue, noncurrent	1,773	1,257
Other liabilities	8,477	7,382
Total liabilities	201,673	175,857
Commitments and contingencies (Note 6)
Stockholders’ equity:
Preferred stock	0	0
Common stock	1,007	971
Additional paid-in capital	686,336	624,026
Accumulated other comprehensive loss	(2,474)	(5,197)
Accumulated deficit	(376,248)	(319,720)
Treasury stock, at cost (0.5 million shares as of June 30, 2017 and December 31, 2016)	(652)	(652)
Total stockholders’ equity	307,969	299,428
Total liabilities and stockholders’ equity	$ 509,642	$ 475,285