Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities
Net loss	$ (2,573)	$ (47,120)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Amortization of patent portfolio	1,598	5,594
Change in fair value of warrant liabilities	(2,055)	774
Stock-based compensation	353	223
Depreciation expenses	1	1
Unrealized loss on marketable securities	62	45
Impairment of goodwill and intangible assets		37,212
Changes in assets and liabilities:
Prepaid expenses and other assets	271	87
Accounts payable and accrued expenses	(320)	(287)
Accrued salaries and benefits	(111)	(114)
Deferred revenue	3,812
Accrued lease liabilities	(133)	(129)
Net cash provided by (used in) operating activities	905	(3,714)
Cash flows from investing activities
Purchase of marketable securities	(15,707)	(3,774)
Purchase of property and equipment	(3)
Sale of marketable securities	12,070	6,454
Net cash (used in) provided by investing activities	(3,640)	2,680
Cash flows from financing activities
Cash paid for cancellation of common stocks	(4)
Cash from issuance common stock, net of offering cost	2,140
Proceeds from exercise of warrants	760
Proceeds from issuance of preferred stock, net		1,321
Redemption of Series I redeemable convertible preferred stock		(935)
Net cash provided by financing activities	2,896	386
Net increase (decrease) in cash and cash equivalents	161	(648)
Cash and cash equivalents, beginning of period	142	805
Cash and cash equivalents, end of period	303	157
Cash paid for interest and taxes
Non-cash investing and financing activities
Extinguishment of Series H Convertible Preferred Stock in connection with license agreement	31,480
Recognition of deferred revenue in connection with license agreement	$ 414