Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 11,062	$ 9,870
Short-term marketable securities	96,605	96,410
Accounts receivable, net of allowances of $1,270 and $1,170	33,922	54,090
Prepaid expenses and other current assets	12,047	13,135
Total current assets	153,636	173,505
Marketable securities, noncurrent	1,006	6,429
Property and equipment, net of accumulated depreciation of $39,297 and $36,344	10,422	12,747
Goodwill	29,753	29,753
Intangible assets, net of accumulated amortization of $24,030 and $22,292	2,808	4,546
Other assets	6,448	8,165
Total assets	204,073	235,145
Current liabilities:
Accounts payable	3,233	3,684
Accrued payroll and related liabilities	8,380	6,954
Other accrued liabilities	5,077	7,842
Deferred revenue, current	116,218	131,850
Term debt, current	2,400	2,400
Total current liabilities	135,308	152,730
Deferred revenue, less current portion	10,155	16,392
Term debt, less current portion	0	1,200
Other long-term liabilities	2,477	2,682
Total liabilities	147,940	173,004
Commitments and contingencies (Note 9)
Stockholders’ Equity:
Common stock, $0.0001 par value. Authorized 290,000 shares; issued – 84,134 shares at June 30, 2016 and 82,820 at December 31, 2015; outstanding – 77,709 at June 30, 2016 and 76,395 at December 31, 2015	7	7
Less treasury stock at cost	(3,352)	(3,352)
Additional paid-in capital	392,473	384,164
Accumulated deficit	(332,671)	(318,537)
Accumulated other comprehensive loss	(324)	(141)
Total stockholders’ equity	56,133	62,141
Total liabilities and stockholders’ equity	$ 204,073	$ 235,145