Commitments and Contingencies (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Rent expense									$ 1,795,000	$ 1,926,000	$ 1,523,000
Other	$ 0	$ 0	$ (1,242,000)	$ 1,742,000	$ 250,000	$ 3,465,000	$ 0	$ 426,000	500,000	4,141,000	$ 1,548,000
Partners' capital, authorized	250,000,000								250,000,000
Cash and other assets, IP Fund	1,118,000				7,740,000				1,118,000	7,740,000
Patents, net of accumulated amortization, IP Fund	0				147,000				0	147,000
Investments, IP Fund	2,933,000				5,829,000				2,933,000	5,829,000
Total assets, IP Fund	4,051,000				13,716,000				4,051,000	13,716,000
Accrued expenses and contributions, IP Fund	2,394,000				7,436,000				2,394,000	7,436,000
Net assets, IP Fund	$ 1,657,000				$ 6,280,000				1,657,000	6,280,000
Revenues, IP Fund									16,000	18,000
IP Fund, Operating expenses									572,000	1,617,000
IP Fund, Gain from Operations									(556,000)	(1,599,000)
IP Fund, Net Loss in Equity Method Investment									(1,013,000)	6,922,000
IP Fund, Net Loss									$ (1,569,000)	$ 5,323,000
Line of Credit Facility, Commitment Fee Percentage									1.15%