Summary of Significant Accounting Policies (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Feb. 16, 2017
Summary of Significant Accounting Policies [Line Items]
Investment in common stock	$ 57,345,000	$ 90,795,000
Investment warrants	6,312,000	13,959,000
Other Cost of Operating Revenue	4,000,000		$ 0
Short-term investments	29,359,000	0
Available-for-sale Securities, Amortized Cost Basis	29,378,000
Available-for-sale Securities, Gross Unrealized Gain	0
Available-for-sale Securities, Gross Unrealized Loss	(19,000)
Available-for-sale Securities	29,359,000
Investments at fair value	63,657,000	104,754,000
Unrealized Gain (Loss) on Investments - Common Stock	(33,450,000)
Unrealized Gain (Loss) on Investment - Warrants	(7,647,000)
Fair Value of Profits Interest	1,313,000			$ 722,000
Change in fair value of investment, net	$ (41,097,000)		$ 0
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%
Write-down of deferred tax assets		$ 25,261,000
Effective tax rate	(1.00%)		(11.00%)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	$ (31,920,000)		$ (10,880,000)
Minimum [Member]
Summary of Significant Accounting Policies [Line Items]
Useful life of patents and patent rights	1 year
Maximum [Member]
Summary of Significant Accounting Policies [Line Items]
Useful life of patents and patent rights	6 years
Fair Value Assumptions, Expected Volatility Rate	50.00%
Geometric Brownian Motion [Member]
Summary of Significant Accounting Policies [Line Items]
Fair Value Assumptions, Expected Term	4 years 5 months
Fair Value Assumptions, Expected Volatility Rate	50.00%
Geometric Brownian Motion [Member] | Minimum [Member]
Summary of Significant Accounting Policies [Line Items]
Fair Value Assumptions, Risk Free Interest Rate	2.00%
Geometric Brownian Motion [Member] | Maximum [Member]
Summary of Significant Accounting Policies [Line Items]
Fair Value Assumptions, Expected Term	10 years
Fair Value Assumptions, Risk Free Interest Rate	3.00%