Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Narrative (Details)

v3.20.2
Summary of Significant Accounting Policies - Narrative (Details)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2020
USD ($)
Sep. 30, 2019
USD ($)
Sep. 30, 2020
USD ($)
business_activity
segment
Sep. 30, 2019
USD ($)
Jun. 30, 2020
USD ($)
Dec. 31, 2019
USD ($)
Jun. 30, 2019
USD ($)
Dec. 31, 2018
USD ($)
Summary Of Significant Accounting Policies [Line Items]                
Number of operating segments | segment     1          
Number of business activities | business_activity     1          
Deferred revenue, revenue recognized $ 22,500 $ 15,100 $ 60,200 $ 44,600        
Contracted but not yet recognized $ 7,400   $ 7,400          
Revenue expected to recognize over next twelve months, percent     6.00%          
Revenue recognized, term, existing deferred revenue     10 years          
Customer agreement, initial term 22 years   22 years          
Customer agreements, initial set up, discount percent     10.00%          
Cumulative effect of adoption of new ASU (No. 2018-02)   (700)            
Cumulative effect of adoption of new ASU (No. 2016-13) $ 1,420,540 $ 1,245,602 $ 1,420,540 $ 1,245,602 $ 1,241,505 $ 1,331,432 $ 1,209,087 $ 1,282,782
Cumulative Effect, Period of Adoption, Adjustment                
Summary Of Significant Accounting Policies [Line Items]                
Cumulative effect of adoption of new ASU (No. 2016-13)           $ (1,228)   $ 0
Minimum                
Summary Of Significant Accounting Policies [Line Items]                
Customer agreement, initial term 20 years   20 years          
Maximum                
Summary Of Significant Accounting Policies [Line Items]                
Customer agreement, initial term 25 years   25 years          
Solar energy systems | Under Customer Agreements                
Summary Of Significant Accounting Policies [Line Items]                
Average age     4 years