Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Current assets
Cash and cash equivalents	$ 7,146	$ 3,125
Prepaid expenses and other assets	87	151
Total current assets	7,233	3,276
Patent portfolios	59,957	64,835
Goodwill	1,712	1,712
Deposit	30	30
Total assets	68,932	69,853
Current liabilities
Accounts payable and accrued expenses	881	270
Accrued salaries and benefits	41	233
Accrued patent cost		1,000
Warrant liability	1	48
Total liabilities	923	1,551
Series I redeemable preferred stock, $0.0001 par value; 35,541 shares issued and outstanding at June 30, 2014 and 119,760 shares issued and outstanding at December 31, 2013; liquidation preference of $167 per share	5,935	20,000
Stockholders' equity
Common stock, $0.0001 par value, 200,000,000 shares authorized; 27,786,655 shares and 3,770,113 shares issued at June 30, 2014 and December 31, 2013, respectively; 27,786,427 and 3,769,712 shares outstanding at June 30, 2014 and December 31, 2013, respectively	3
Additional paid-in-capital	135,142	102,043
Treasury stock, at cost, 228 shares at June 30, 2014 and 401 shares at December 31, 2013	(264)	(465)
Accumulated deficit	(72,807)	(53,276)
Total stockholders' equity	62,074	48,302
Total liabilities and stockholders' equity	68,932	69,853
Series A Preferred Stock [Member]
Stockholders' equity
Preferred stock
Series J Preferred Stock [Member]
Stockholders' equity
Preferred stock
Series B Preferred Stock [Member]
Stockholders' equity
Preferred stock
Series C Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock
Series D Preferred Stock [Member]
Stockholders' equity
Preferred stock
Series D-1 Preferred [Member]
Stockholders' equity
Preferred stock
Series E Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock
Series F Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock
Series F-1 Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock
Series H Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock