Consolidated Statements of Cash Flows Statement (USD $)	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Payments of Dividends	$ (6,149,000)	$ 0
Patent acquisition costs included in accrued expenses	8,508,000	10,200,000
Cash flows from operating activities:
Net income (loss) including noncontrolling interests in operating subsidiaries	(8,367,000)	56,034,000
Adjustments to reconcile net income including noncontrolling interests in operating subsidiaries to net cash provided by operating activities:
Depreciation and amortization	24,405,000	10,585,000
Non-cash stock compensation	11,426,000	11,090,000
Excess tax benefits from stock-based compensation	847,000	10,850,000
Change in valuation allowance	0	(10,237,000)
Other	0	49,000
Changes in assets and liabilities:
Accounts receivable	(6,938,000)	(7,907,000)
Prepaid expenses and other assets	(5,863,000)	(271,000)
Accounts payable and accrued expenses / costs	7,362,000	13,795,000
Royalties and contingent legal fees payable	7,478,000	(4,405,000)
Deferred income tax	(10,552,000)	5,522,000
Net cash provided by operating activities	18,104,000	63,405,000
Cash flows from investing activities:
Purchases of property and equipment	(365,000)	(188,000)
Purchase of available-for-sale investments	(175,042,000)	(239,952,000)
Maturities and sale of available-for-sale investments	93,809,000	117,462,000
Purchase of ADAPTIX, Inc., net of cash acquired	0	(150,000,000)
Patent acquisition costs	(6,260,000)	(40,435,000)
Net cash used in investing activities	(87,858,000)	(313,113,000)
Cash flows from financing activities:
Proceeds from sale of common stock, net of issuance costs	0	218,983,000
Contributions from noncontrolling interests in operating subsidiary	1,920,000	1,920,000
Excess tax benefits from stock-based compensation	847,000	10,850,000
Proceeds from exercises of stock options	241,000	88,000
Net cash provided by financing activities	(3,141,000)	231,841,000
Decrease in cash and cash equivalents	(72,895,000)	(17,867,000)
Cash and cash equivalents, beginning	221,804,000	314,733,000
Cash and cash equivalents, ending	$ 148,909,000