Annual report pursuant to Section 13 and 15(d)

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

v3.19.1
Property and Equipment - Components of Property and Equipment (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Property, Plant and Equipment [Line Items]    
Total property and equipment $ 14,583 $ 8,287
Less: Accumulated depreciation (2,564) (1,171)
Property and equipment, net 12,019 7,116
Computer Equipment [Member] | Fortress Biotech Inc [Member]    
Property, Plant and Equipment [Line Items]    
Total property and equipment $ 648 543
Useful Life (Years) 3 years  
Furniture and Fixtures [Member] | Fortress Biotech Inc [Member]    
Property, Plant and Equipment [Line Items]    
Total property and equipment $ 1,128 1,009
Useful Life (Years) 5 years  
Leasehold Improvements [Member] | Fortress Biotech Inc [Member]    
Property, Plant and Equipment [Line Items]    
Total property and equipment $ 9,271 5,351
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] $ 393 1,241
Machinery and Equipment [Member] | Fortress Biotech Inc [Member]    
Property, Plant and Equipment [Line Items]    
Total property and equipment $ 3,143 $ 143
Useful Life (Years) 5 years  
[1] Note 1: Relates to the Mustang cell processing facility.