CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current Assets:
Cash and cash equivalents	$ 32,838	$ 111,897
Marketable securities	31,020	25,263
Prepaid expenses and other current assets	5,810	1,684
Total current assets	69,668	138,844
Property and equipment, net	2,145	123
Ownership interests in and advances to partner companies	171,601	154,192
Loan participations receivable	2,649	3,855
Long-term marketable securities	9,743	19,365
Other assets	1,828	2,075
Total Assets	257,634	318,454
Current Liabilities:
Accounts payable	290	226
Accrued compensation and benefits	3,338	3,997
Accrued expenses and other current liabilities	2,789	2,334
Total current liabilities	6,417	6,557
Other long-term liabilities	3,965	3,507
Convertible senior debentures—non-current	51,747	50,563
Total Liabilities	$ 62,129	$ 60,627
Commitments and contingencies
Equity:
Preferred stock, $0.10 par value; 1,000 shares authorized	$ 0	$ 0
Common stock, $0.10 par value; 83,333 shares authorized; 21,573 issued at December 31, 2015 and 2014, respectively	2,157	2,157
Additional paid-in capital	817,434	819,757
Treasury stock, at cost; 993 and 921 shares at December 31, 2015 and 2014, respectively	(19,570)	(19,341)
Accumulated deficit	(604,270)	(544,746)
Accumulated other comprehensive loss	(246)	0
Total Equity	195,505	257,827
Total Liabilities and Equity	$ 257,634	$ 318,454