Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Assets
Cash and cash equivalents	$ 30,527	$ 31,068
Short-term investments	1,493	1,497
Restricted cash equivalents and short-term investments	1,000	1,000
Prepaid expenses and other current assets	148	169
Total current assets	33,168	33,734
Property and equipment, net	27	32
Other assets	27	27
Total assets	33,222	33,793
Liabilities and stockholders’ equity
Accounts payable	149	234
Accrued expenses	312	346
Total current liabilities	461	580
Income tax liability	101	101
Total liabilities	562	681
Commitments and contingencies
Common stock	11	11
Paid-in capital	221,726	221,726
Treasury stock	(6,788)	(6,788)
Unrealized loss on available-for-sale securities	(1)
Accumulated deficit	(182,288)	(181,837)
Total stockholders’ equity	32,660	33,112
Total liabilities and stockholders’ equity	$ 33,222	$ 33,793