Annual report pursuant to Section 13 and 15(d)

Other Assets

Other Assets
12 Months Ended
Dec. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]  
Other Assets Other Assets
Other assets consist of the following (in thousands): 
December 31,
2020 2019
Costs to obtain contracts - customer agreements $ 377,839  $ 268,964 
Costs to obtain contracts - incentives 2,481  2,481 
Accumulated amortization of costs to obtain contracts (51,365) (36,925)
Unbilled receivables 150,603  105,574 
Allowance for credit loss on unbilled receivables (1,731) (1,228)
Operating lease right-of-use assets 81,516  34,678 
Equity method investment 65,356  — 
Other assets 56,966  34,859 
Total $ 681,665  $ 408,403 
    The Company recorded amortization of costs to obtain contracts of $14.4 million and $11.8 million for the years ended December 31, 2020 and 2019, respectively, in the sales and marketing expense.

    The majority of unbilled receivables arise from fixed price escalators included in the Company’s long-term Customer Agreements.  The escalator is included in calculating the total estimated transaction value for an individual Customer Agreement.  The total estimated transaction value is then recognized over the term of the Customer Agreement. The amount of unbilled receivables increases while cumulative billings for an individual Customer Agreement are less than the cumulative revenue recognized for that Customer Agreement.  Conversely, the amount of unbilled receivables decreases when the actual cumulative billings becomes higher than the cumulative revenue recognized. At the end of the initial term of a Customer Agreement, the cumulative amounts recognized as revenue and billed to date are the same, therefore the unbilled receivable balance for an individual Customer Agreement will be zero. As a result of the adoption of ASU No. 2016-13, an allowance for credit loss on unbilled receivables was established as of January 1, 2020. The Company applies an estimated loss-rate in order to determine the current expected credit loss for unbilled receivables. The estimated loss-rate is determined by analyzing historical credit losses, residential first and second mortgage foreclosures and consumers' utility default rates, as well as current economic conditions. The Company reviews individual customer collection status of electricity billings to determine whether the unbilled receivables for an individual customer should be written off, including the possibility of a service transfer to a potential new homeowner.