Annual report pursuant to Section 13 and 15(d)

Non-Controlling Interests - Summary Of Non-controlling Interests in Consolidated Entities (Detail)

v3.8.0.1
Non-Controlling Interests - Summary Of Non-controlling Interests in Consolidated Entities (Detail) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2017
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2016
Sep. 30, 2016
Jun. 30, 2016
Mar. 31, 2016
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Noncontrolling Interest [Line Items]                      
NCI equity share                 $ 100,889 $ 60,668 $ 32,882
Net loss attributed to non-controlling interests $ 15,605 $ 9,191 $ 5,584 $ 2,580 $ 3,871 $ 3,975 $ 3,911 $ 4,438 (32,960) (16,195) (5,455)
Non-controlling interests in consolidated entities 67,929       44,473       67,929 44,473 27,427
Aevitas [Member]                      
Noncontrolling Interest [Line Items]                      
NCI equity share                 (126)    
Net loss attributed to non-controlling interests                 (168)    
Non-controlling interests in consolidated entities $ (294)               $ (294)    
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners 35.40%               35.40%    
Avenue [Member]                      
Noncontrolling Interest [Line Items]                      
NCI equity share                 $ 17,454 [1] (494) 6
Net loss attributed to non-controlling interests                 (4,646) [1] (349) (567)
Non-controlling interests in consolidated entities $ 12,808 [1]       $ (843)       $ 12,808 [1] $ (843) $ (561)
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners 66.10% [1]       10.20%       66.10% [1] 10.20% 11.50%
Caelum [Member]                      
Noncontrolling Interest [Line Items]                      
NCI equity share                 $ (815)    
Net loss attributed to non-controlling interests                 (1,262)    
Non-controlling interests in consolidated entities $ (2,077)               $ (2,077)    
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners 34.70%               34.70%    
Cellvation [Member]                      
Noncontrolling Interest [Line Items]                      
NCI equity share                 $ (259) $ 4  
Net loss attributed to non-controlling interests                 (96) (158)  
Non-controlling interests in consolidated entities $ (355)       $ (154)       $ (355) $ (154)  
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners 21.50%       22.00%       21.50% 22.00%  
Checkpoint Therapeutics, Inc [Member]                      
Noncontrolling Interest [Line Items]                      
NCI equity share [2]                 $ 21,635 $ 32,160 $ 32,760
Net loss attributed to non-controlling interests [2]                 (12,314) (11,733) (3,855)
Non-controlling interests in consolidated entities [2] $ 9,321       $ 20,427       $ 9,321 $ 20,427 $ 28,905
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners [2] 62.00%       62.90%       62.00% 62.90% 62.30%
Coronado SO Co, Inc [Member]                      
Noncontrolling Interest [Line Items]                      
NCI equity share                 $ (236) $ (217) $ 23
Net loss attributed to non-controlling interests                 (54) (19) (240)
Non-controlling interests in consolidated entities $ (290)       $ (236)       $ (290) $ (236) $ (217)
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners 13.00%       13.00%       13.00% 13.00% 13.00%
Cyprium [Member]                      
Noncontrolling Interest [Line Items]                      
NCI equity share                 $ (143)    
Net loss attributed to non-controlling interests                 (15)    
Non-controlling interests in consolidated entities $ (158)               $ (158)    
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners 11.10%               11.10%    
Helocyte [Member]                      
Noncontrolling Interest [Line Items]                      
NCI equity share                 $ (1,907) $ (612)  
Net loss attributed to non-controlling interests                 (1,193) (1,155)  
Non-controlling interests in consolidated entities $ (3,100)       $ (1,767)       $ (3,100) $ (1,767)  
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners 20.00%       20.50%       20.00% 20.50%  
JMC [Member]                      
Noncontrolling Interest [Line Items]                      
NCI equity share                 $ (469) $ (192) $ 79
Net loss attributed to non-controlling interests                 7 (355) (420)
Non-controlling interests in consolidated entities $ (462)       $ (547)       $ (462) $ (547) $ (341)
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners 6.30%       7.00%       6.30% 7.00% 8.80%
Mustang Therapeutics, Inc [Member]                      
Noncontrolling Interest [Line Items]                      
NCI equity share                 $ 48,740 [1] $ 12,376 $ 14
Net loss attributed to non-controlling interests                 (11,911) [1] (1,805) (373)
Non-controlling interests in consolidated entities $ 36,829 [1]       $ 10,571       $ 36,829 [1] $ 10,571 $ (359)
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners 61.60% [1]       26.70%       61.60% [1] 26.70% 10.00%
National Holdings [Member]                      
Noncontrolling Interest [Line Items]                      
NCI equity share                 $ 17,021 $ 17,643  
Net loss attributed to non-controlling interests                 (1,216) (621)  
Non-controlling interests in consolidated entities $ 15,805       $ 17,022       $ 15,805 $ 17,022  
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners 43.40%       43.40%       43.40% 43.40%  
Tamid [Member]                      
Noncontrolling Interest [Line Items]                      
NCI equity share                 $ (6)    
Net loss attributed to non-controlling interests                 (92)    
Non-controlling interests in consolidated entities $ (98)               $ (98)    
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners 24.00%               24.00%    
[1] Avenue and Mustang are consolidated with Fortress’ operations because Fortess maintains voting control through its ownership of Preferred Class A Shares which provide super-majority voting rights.
[2] Checkpoint is consolidated with Fortress’ operations because Fortress maintains voting control through its ownership of Checkpoint’s Class A Common Shares which provide super-majority voting rights.