Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 25,256	$ 6,030
Marketable securities	170,647	172,932
Interest receivable	398	423
Accounts receivable	6,638	10,368
Prepaid expenses	587	623
Restricted cash	320	320
Other current assets	100	183
Total current assets	203,946	190,879
Marketable securities, non-current	29,822	47,260
Property and equipment, net	2,995	1,479
Intangible assets, in-process research and development	0	1,870
Goodwill	1,585	1,585
Other assets	157	139
Total assets	238,505	243,212
Current liabilities:
Accounts payable and accrued liabilities	6,806	8,704
Accrued compensation and employee benefits	1,703	2,853
Escrow liability	275	275
Deferred revenues	11,184	9,050
Total current liabilities	19,968	20,882
Deferred revenues, non-current	11,049	13,149
Contingent consideration liability		1,800
Deferred tax liability		748
Total liabilities	31,017	36,579
Commitments and contingencies
Stockholders' equity:
Common stock, $0.01 par value; 160,000,000 shares authorized, 69,497,256 and 69,062,394 shares issued and outstanding at March 31, 2015, and December 31, 2014, respectively	695	690
Additional paid-in capital	540,637	534,518
Accumulated deficit	(333,869)	(328,550)
Accumulated other comprehensive income (loss)	25	(25)
Total stockholders' equity	207,488	206,633
Total liabilities and stockholders' equity	$ 238,505	$ 243,212