Annual report pursuant to Section 13 and 15(d)

Commitments and Contingencies (Narrative) (Detail)

v3.19.1
Commitments and Contingencies (Narrative) (Detail)
 1 Months Ended 2 Months Ended 5 Months Ended 12 Months Ended
Mar. 11, 2019
USD ($)
Apr. 06, 2018
USD ($)
Feb. 28, 2019
claim
Oct. 31, 2018
USD ($)
plaintiff
Jan. 31, 2016
USD ($)
underwriter
Nov. 30, 2015
USD ($)
security_offering
firm
claim
May 31, 2014
USD ($)
employee
Jul. 31, 2013
USD ($)
plaintiff
Jan. 31, 2015
claim
May 31, 2017
USD ($)
claim
Dec. 31, 2018
USD ($)
claim
Jan. 01, 2018
USD ($)
Dec. 31, 2017
USD ($)
Loss Contingencies [Line Items]                          
Deferred rent                     $ 2,956,000 $ 2,151,000 $ 2,151,000
Number of firms that underwrote security offerings | firm           9              
Number of security offerings | security_offering           6              
Accrued liabilities                     $ 9,869,000   $ 6,902,000
Convertible Notes Payable                          
Loss Contingencies [Line Items]                          
Offering               $ 300,000,000          
Common Stock                          
Loss Contingencies [Line Items]                          
Offering             $ 1,656,000            
Ladenburg                          
Loss Contingencies [Line Items]                          
New claims filed | claim                   5      
Number of underwriters | underwriter         1                
Securities America                          
Loss Contingencies [Line Items]                          
Number of complaints | claim                     2    
Number of plaintiffs | plaintiff       14                  
Damages sought by plaintiff   $ 5,828,000   $ 18,000,000                  
Compensatory damages                          
Loss Contingencies [Line Items]                          
New claims filed | claim           2     2        
Number of plaintiffs | employee             17            
Damages sought by plaintiff           $ 151,000,000       $ 5,400,000      
Compensatory damages | Ladenburg                          
Loss Contingencies [Line Items]                          
Damages sought by plaintiff         $ 2,900,000,000                
ARCP July 2013 Offering | Compensatory damages                          
Loss Contingencies [Line Items]                          
Number of plaintiffs | plaintiff               8          
Subsequent event | Securities America                          
Loss Contingencies [Line Items]                          
Number of complaints | claim     1                    
Damages sought by plaintiff $ 2,149,000