Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 13,450	$ 20,471
Marketable securities, available-for-sale	23,258	23,499
Restricted cash	3,246	3,182
Receivables and other assets	4,544	4,178
Total current assets	44,498	51,330
Long-term investments	2,052	1,971
Property and equipment, net	1,873	2,639
Intangible assets, net	1,300	1,660
Other assets	191	379
Total assets	49,914	57,979
Current liabilities:
Accounts payable and accrued expenses	3,912	5,201
Deferred revenue	250	0
Total current liabilities	4,162	5,201
Long-term liabilities:
Deferred rent	$ 359	$ 856
Commitments and contingencies (Notes 6 and 7)
Stockholders’ equity:
Preferred stock, $0.01 par value, 5,000 shares authorized, none issued and outstanding	$ 0	$ 0
Common stock, $0.01 par value, 160,000 shares authorized, 91,544 and 90,334 shares issued and outstanding at December 31, 2015 and 2014, respectively	915	903
Additional paid-in capital	449,343	446,698
Accumulated deficit	(404,905)	(395,667)
Accumulated other comprehensive income (loss)	40	(12)
Total stockholders’ equity	45,393	51,922
Total liabilities and stockholders’ equity	$ 49,914	$ 57,979