Annual report pursuant to Section 13 and 15(d)

Property and Equipment - Components of Property and Equipment (Detail)

v3.6.0.2
Property and Equipment - Components of Property and Equipment (Detail) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2016
Sep. 30, 2016
Dec. 31, 2015
Property, Plant and Equipment [Line Items]      
Total property and equipment   $ 1,200  
Less: Accumulated depreciation   (36)  
Property and equipment, net $ 7,376 1,164 $ 309
Fortress Biotech Inc [Member]      
Property, Plant and Equipment [Line Items]      
Total property and equipment 6,657   377
Less: Accumulated depreciation (445)   (68)
Property and equipment, net 6,212   309
Computer Equipment [Member] | Fortress Biotech Inc [Member]      
Property, Plant and Equipment [Line Items]      
Total property and equipment $ 440   13
Useful Life (Years) 3 years    
Furniture and Fixtures [Member]      
Property, Plant and Equipment [Line Items]      
Total property and equipment   65  
Furniture and Fixtures [Member] | Fortress Biotech Inc [Member]      
Property, Plant and Equipment [Line Items]      
Total property and equipment $ 821   69
Useful Life (Years) 5 years    
Leasehold Improvements [Member]      
Property, Plant and Equipment [Line Items]      
Total property and equipment   $ 259  
Leasehold Improvements [Member] | Fortress Biotech Inc [Member]      
Property, Plant and Equipment [Line Items]      
Total property and equipment $ 5,396   21
Leasehold Improvements [Member] | Fortress Biotech Inc [Member] | Maximum [Member]      
Property, Plant and Equipment [Line Items]      
Useful Life (Years) 15 years    
Leasehold Improvements [Member] | Fortress Biotech Inc [Member] | Minimum [Member]      
Property, Plant and Equipment [Line Items]      
Useful Life (Years) 5 years    
Construction in progress [Member] | Fortress Biotech Inc [Member]      
Property, Plant and Equipment [Line Items]      
Total property and equipment [1] $ 0   $ 274
[1] For build-out of the Company's new office in New York, NY.