XML 184 R164.htm IDEA: XBRL DOCUMENT v3.21.1
SPECIAL PURPOSE ENTITIES - Additional information (Details) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]        
Loans Payable, Current $ 18,052   $ 14,914 $ 6,373
Loans Payable, Noncurrent 70,059   73,128 74,640
Interest Expense 6,233 $ 4,369 20,806 12,548
Equity Method Investment, Summarized Financial Information [Abstract]        
Energy storage systems, net 119,842   123,703 131,569
Deferred revenue, current 38,762   36,942 10,948
Deferred revenue, noncurrent $ 16,640   15,468 9,780
Unconsolidated SPEs        
Related Party Transactions        
Revenues recognized associated with sales to the unconsolidated SPEs     12,800 8,800
Cost of service recognized associated with sales to the unconsolidated SPEs     11,800 7,100
Energy Storage Systems        
Equity Method Investment, Summarized Financial Information [Abstract]        
Energy storage systems, net     91,593 98,358
Deferred revenue, current     3,713 3,507
Deferred revenue, noncurrent     8,265 6,302
Other liabilities     3,178 2,608
Financing obligation        
Schedule of Equity Method Investments [Line Items]        
Loans Payable, Current     14,914 6,373
Loans Payable, Noncurrent     73,128 74,640
Interest Expense     $ 6,900 $ 5,800