Quarterly report pursuant to Section 13 or 15(d)

Commitments and Contingencies (Detail)

v3.10.0.1
Commitments and Contingencies (Detail)
$ in Thousands
 1 Months Ended 2 Months Ended 3 Months Ended 6 Months Ended 15 Months Ended 24 Months Ended
Apr. 06, 2018
USD ($)
Nov. 30, 2015
claim
Jan. 31, 2015
USD ($)
note_offering
claim
underwriter
Jun. 30, 2018
USD ($)
Jun. 30, 2018
USD ($)
Jul. 31, 2017
USD ($)
claim
Dec. 31, 2014
USD ($)
security_offering
firm
underwriter
Jun. 30, 2017
USD ($)
Mar. 31, 2016
USD ($)
Loss Contingencies [Line Items]                  
Number of prior note offerings | note_offering     3            
Number of firms that underwrote security offerings | firm             9    
Number of security offerings | security_offering             6    
Loss in period       $ 421 $ 2,993        
Loss contingency accrual, product liability       9,160 9,160     $ 6,902  
Future minimum payments due       70,199 70,199        
Subsidiaries                  
Loss Contingencies [Line Items]                  
Office space lease term                 12 years
Estimated annual rent expense                 $ 2,000
Securities America                  
Loss Contingencies [Line Items]                  
Damages sought by plaintiff $ 5,800                
Ladenburg                  
Loss Contingencies [Line Items]                  
New claims filed, number | claim           5      
Number of underwriters | underwriter             1    
Number of security offerings | security_offering             2    
Highland                  
Loss Contingencies [Line Items]                  
Future minimum payments due       $ 174 174        
Convertible Notes Payable                  
Loss Contingencies [Line Items]                  
Proceeds from issuance Public Offering     $ 300,000            
Common Stock                  
Loss Contingencies [Line Items]                  
Proceeds from issuance Public Offering     $ 1,656,000            
Compensatory damages                  
Loss Contingencies [Line Items]                  
New claims filed, number | claim   2 2            
Number of underwriters | underwriter     1            
Number of plaintiffs | underwriter     17            
Damages sought by plaintiff           $ 5,400 $ 151,000    
Compensatory damages | Ladenburg                  
Loss Contingencies [Line Items]                  
Damages sought by plaintiff             $ 2,900,000    
Compensatory damages | ARCP July 2013 Offering                  
Loss Contingencies [Line Items]                  
Number of underwriters | underwriter     1            
Number of plaintiffs | underwriter     8            
SEC Initiative                  
Loss Contingencies [Line Items]                  
Loss in period         $ 2,306