Consolidated Statements of Cash Flows (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities:
Net income (loss) including noncontrolling interests in operating subsidiaries	$ 21,645,000	$ 37,016,000	$ (5,633,000)
Adjustments to reconcile net income including noncontrolling interests in operating subsidiaries to net cash provided by operating activities:
Depreciation and amortization	9,850,000	7,017,000	4,759,000
Non-cash stock compensation	13,579,000	7,121,000	7,065,000
(Gain) loss on investments	(15,000)	(32,000)	47,000
Changes in assets and liabilities:
Accounts receivable	5,072,000	(2,877,000)	2,326,000
Prepaid expenses and other assets	1,075,000	(757,000)	(106,000)
Accounts payable and accrued expenses	(1,364,000)	(1,414,000)	4,836,000
Royalties and contingent legal fees payable	10,748,000	358,000	1,632,000
Deferred revenues	0	(1,510,000)	1,192,000
Net cash provided by operating activities	60,590,000	44,922,000	16,118,000
Cash flows from investing activities:
Purchases of property and equipment	(190,000)	(58,000)	(67,000)
Purchase of available-for-sale investments	(8,427,000)	0	0
Sale of available-for-sale investments	60,000	184,000	1,040,000
Patent acquisition costs	(14,680,000)	(8,224,000)	(9,625,000)
Net cash used in investing activities	(23,237,000)	(8,098,000)	(8,652,000)
Cash flows from financing activities:
Proceeds from sale of common stock, net of issuance costs	175,229,000	0	0
Distributions to noncontrolling interests in operating subsidiary	(2,897,000)	(4,807,000)	(3,150,000)
Contributions from noncontrolling interests in operating subsidiary	1,539,000	2,393,000	0
Repurchased restricted common stock	0	0	(1,107,000)
Proceeds from exercises of stock options	411,000	15,068,000	247,000
Excess tax benefits from stock-based compensation	583,000	1,302,000	0
Net cash provided by (used in) financing activities	174,865,000	13,956,000	(4,010,000)
Increase in cash and cash equivalents	212,218,000	50,780,000	3,456,000
Cash and Cash Equivalents, beginning	102,515,000	51,735,000	48,279,000
Cash and Cash Equivalents, ending	314,733,000	102,515,000	51,735,000
Additional Paid-in Capital [Member]
Adjustments to reconcile net income including noncontrolling interests in operating subsidiaries to net cash provided by operating activities:
Non-cash stock compensation	13,578,000	7,120,000	7,064,000
Cash flows from financing activities:
Proceeds from sale of common stock, net of issuance costs	175,223,000
Repurchased restricted common stock			(1,107,000)
Proceeds from exercises of stock options	411,000	15,065,000	247,000
Excess tax benefits from stock-based compensation	$ 583,000	$ 1,302,000