Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements - Additional Information (Detail)

v3.8.0.1
Fair Value Measurements - Additional Information (Detail) - USD ($)
 1 Months Ended 5 Months Ended 12 Months Ended
Jun. 26, 2017
Oct. 31, 2016
Sep. 30, 2016
Oct. 30, 2015
Mar. 17, 2014
Mar. 17, 2014
Aug. 31, 2015
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Dec. 01, 2017
Jun. 01, 2017
Dec. 30, 2016
Sep. 18, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                            
Equity Method Investments         $ 250,000 $ 250,000   $ 300,000 $ 300,000          
Equity Method Investment, Ownership Percentage         35.00% 35.00%                
Fair Value Assumptions, Exercise Price               $ 1.01            
Fair Value Assumptions, Expected Volatility Rate               70.00%            
Share Price                     $ 3.83 $ 2.24    
Investments in and Advances to Affiliates, at Fair Value, Period Increase (Decrease), Total               $ 200,000 1,100,000          
Investment Owned, at Fair Value               1,985,000 2,357,000          
Fair Value Adjustment of Warrants               $ (8,391,000) $ 1,039,000 $ 438,000        
Warrants Issued       139,592                    
Value of Warrants Issued       $ 600,000     $ 200,000              
Class of Warrant or Right, Exercise Price of Warrants or Rights $ 4.02             $ 2,500           $ 7.00
Equity Securities Called by Warrant                         $ 10,000  
Debt Conversion, Converted Instrument, Shares Issued 49,749                          
Exercise Price Of Warrant Discount Percentage 33.00%                          
Common Stock Par Or Stated Value Per Share               $ 0.001 $ 0.001   $ 3.26 $ 1.90    
Class of Warrant or Right, Number of Securities Called by Warrants or Rights               7.00            
Stock Issued During Period, Value, New Issues                 $ 53,000,000          
Investment Write Down         $ 300,000                  
Origo Acquisition Corporation [Member]                            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                            
Investment Owned, at Fair Value               $ 1,400,000 $ 1,200,000          
Investments In Subsidiary Number Of Shares Transferred To Subsidiary               1,050,000            
Investments In Subsidiary Number Of Shares Outstanding               265,000            
Fair Value Assumptions Probability Of Business Combination               46.53% 51.53%          
Working Capital Note Convertible To Equity               $ 300,000            
National Holdings Corporation [Member]                            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                            
Percentage of Outstanding Stock To Be Issued Upon Exercise of Warrants     44.00%                      
Percentage of outstanding shares, Tendered     80.00%                      
Class of Warrant or Right, Exercise Price of Warrants or Rights     $ 3.25                      
Warrants Not Settleable in Cash, Fair Value Disclosure     $ 5,400,000                      
Class of Warrant or Right, Number of Securities Called by Warrants or Rights 125,000                          
Debt Instrument, Face Amount $ 3,000,000                          
Mustang Bio, Inc. [Member]                            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                            
Number of Warrants Issued   138,462                        
Contingently Issuance Warrants   $ 800,000                        
Westpark [Member]                            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                            
Class of Warrant or Right, Exercise Price of Warrants or Rights $ 4.02                          
Exercise Price Of Warrant Discount Percentage 33.00%                          
Common Stock Par Or Stated Value Per Share $ 6.00                          
Class of Warrant or Right, Number of Securities Called by Warrants or Rights 2,488                          
Avenue Therapeutics, Inc. [Member]                            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                            
Common Stock Par Or Stated Value Per Share $ 6.00                          
Stock Issued During Period, Value, New Issues $ 38,000,000                          
Binomial Lattice Model [Member]                            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                            
Fair Value Assumptions, Exercise Price               $ 11.50            
Risk free rate               1.28% 0.85%          
Binomial Lattice Model [Member] | Warrant [Member]                            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                            
Business Acquisition, Share Price               $ 1.06 $ 0.82          
Ghaidarov Model [Member] | Warrant [Member]                            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                            
Business Acquisition, Share Price               1.07 0.58          
Private Units [Member]                            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                            
Share Price               $ 10.65 $ 8.16          
Argus Neurooptics Llc [Member] | Class A Preferred Stock [Member]                            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]                            
Shares Received Under Purchase Agreement           $ 13,409,962                
Percentage Of Shares Received Under Purchase Agreement           83.00%                
Preferred Units, Issued         16,091,954 16,091,954