Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation and Significant Accounting Policies - Additional Information (Details)

v3.19.2
Basis of Presentation and Significant Accounting Policies - Additional Information (Details)
3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2019
USD ($)
Customer
Jun. 30, 2018
USD ($)
Customer
Jun. 30, 2019
USD ($)
Customer
Jun. 30, 2018
USD ($)
Customer
Dec. 31, 2018
USD ($)
Customer
Jan. 01, 2019
USD ($)
Basis Of Presentation And Significant Accounting Policies [Line Items]            
Operating lease right-of-use assets $ 6,417,000   $ 6,417,000      
Operating lease liabilities 8,103,000   8,103,000      
Dividends declared $ 0 $ 0 $ 0 $ 0    
Customer Concentration Risk [Member] | Trade Receivables [Member]            
Basis Of Presentation And Significant Accounting Policies [Line Items]            
Number of major partners | Customer     1   2  
Customer Concentration Risk [Member] | Trade Receivables [Member] | Partner 1 [Member]            
Basis Of Presentation And Significant Accounting Policies [Line Items]            
Concentration risk, percentage (in hundredths)     100.00%   67.00%  
Customer Concentration Risk [Member] | Trade Receivables [Member] | Partner 2 [Member]            
Basis Of Presentation And Significant Accounting Policies [Line Items]            
Concentration risk, percentage (in hundredths)         28.00%  
Customer Concentration Risk [Member] | Revenues [Member]            
Basis Of Presentation And Significant Accounting Policies [Line Items]            
Number of major partners | Customer 3 2 1 2    
Customer Concentration Risk [Member] | Revenues [Member] | Partner 1 [Member]            
Basis Of Presentation And Significant Accounting Policies [Line Items]            
Concentration risk, percentage (in hundredths) 52.00% 80.00% 88.00% 66.00%    
Customer Concentration Risk [Member] | Revenues [Member] | Partner 2 [Member]            
Basis Of Presentation And Significant Accounting Policies [Line Items]            
Concentration risk, percentage (in hundredths) 35.00% 11.00%   22.00%    
Customer Concentration Risk [Member] | Revenues [Member] | Partner 3 [Member]            
Basis Of Presentation And Significant Accounting Policies [Line Items]            
Concentration risk, percentage (in hundredths) 10.00%          
ASC 842 [Member]            
Basis Of Presentation And Significant Accounting Policies [Line Items]            
Operating lease right-of-use assets           $ 7,400,000
Operating lease liabilities           $ 9,200,000
ASC 842 [Member] | Lease-related Costs [Member]            
Basis Of Presentation And Significant Accounting Policies [Line Items]            
Lease-related restructuring liabilities, carrying amount         $ 1,700,000