Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net income (loss) including noncontrolling interests in operating subsidiaries	$ (104,848)	$ 21,684
Adjustments to reconcile net income (loss) including noncontrolling interests in operating subsidiaries to net cash provided by (used in) operating activities:
Gain on Conversion of Loan and Accrued Interest	0	(2,671)
Gain on exercise of Primary Warrant	0	(4,616)
Change in fair value of investment	59,103	(42,239)
Loss on Sale of Investments	19,095	0
Depreciation and amortization	27,145	22,243
Non-cash stock compensation	(317)	8,885
Impairment of Patent-Related Intangible Assets	28,210	2,248
Other	564	(374)
Changes in assets and liabilities:
Accounts receivable	(28,189)	26,597
Prepaid expenses and other assets	(208)	(135)
Accounts payable and accrued expenses / costs	963	(6,349)
Royalties and contingent legal fees payable	19,359	(12,307)
Net cash provided by (used in) operating activities	20,877	12,966
Cash flows from investing activities:
Payments to Acquire Other Investments	(7,000)	(31,514)
Proceeds from Sale of Other Assets, Investing Activities	19,097	0
Payments to Acquire Notes Receivable	0	(4,000)
Purchase of property and equipment	(34)	(2)
Purchase of available-for-sale investments	(102,769)	(448,388)
Sale of available-for-sale investments	66,640	467,790
Net cash provided by (used in) investing activities	(24,066)	(16,114)
Cash flows from financing activities:
Proceeds from the exercise of stock options	257	745
Repurchase of restricted common stock	(229)	(45)
Repurchases of common stock	(4,634)	0
Net cash provided by (used in) financing activities	(4,606)	700
Increase in cash and cash equivalents	(7,795)	(2,448)
Cash and cash equivalents, beginning	136,604	139,052
Cash and cash equivalents, ending	$ 128,809	$ 136,604