CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current assets
Cash and cash equivalents	$ 42,842	$ 58,750
Marketable securities	10,995	17,420
Accounts receivable, net of allowance for doubtful accounts of $794 and $713 at September 30, 2016 and December 31, 2015, respectively	22,353	15,647
Deferred commissions	1,634	1,368
Other receivables	1,261	818
Prepaid expenses and other current assets	4,972	3,875
Total current assets	84,057	97,878
Property and equipment, net	43,287	44,410
Intangible assets, net	995	896
Other assets	1,583	711
Total assets	129,922	143,895
Current liabilities
Accounts payable	5,637	5,138
Accrued expenses and other current liabilities	17,177	20,394
Deferred revenue	63,629	55,741
Deferred government grant obligation	1,164	985
Current portion of capital lease and financing obligations	1,432	1,808
Current portion of long-term debt	20	18
Total current liabilities	89,059	84,084
Deferred revenue	15,216	7,597
Deferred government grant obligation	1,089	1,996
Other long-term liabilities	4,064	3,343
Capital lease and financing obligations	20,013	21,083
Long-term debt	53	73
Total liabilities	129,494	118,176
Stockholders’ equity
Preferred stock, $0.001 par value per share, 100,000,000 shares authorized, no shares issued and outstanding	0	0
Additional paid-in-capital	213,532	202,371
Accumulated deficit	(213,395)	(176,934)
Accumulated other comprehensive income	250	241
Total stockholders’ equity	428	25,719
Total liabilities and stockholders’ equity	129,922	143,895
Class A Common Stock
Stockholders’ equity
Common stock	30	29
Class B Common Stock
Stockholders’ equity
Common stock	$ 11	$ 12