Commitments and Contingencies	6 Months Ended
Jun. 30, 2021
Commitments and Contingencies
Commitments and Contingencies	19. Commitments and Contingencies Restricted Cash In connection with certain of the above noted sale/leaseback agreements, cash of $243.5 million was required to be restricted as security as of June 30, 2021, which restricted cash will be released over the lease term. As of June 30, 2021, the Company also had certain letters of credit backed by restricted cash totaling $143.7 million that are security for the above noted sale/leaseback agreements. Litigation Legal matters are defended and handled in the ordinary course of business. Liabilities for loss contingencies arising from claims, assessments, litigation, fines, and penalties and other sources are recorded when it is probable that a liability has been incurred and the amount can be reasonably estimated. Legal costs incurred in connection with loss contingencies are expensed as incurred. The Company has not recorded any accruals related to any legal matters. Concentrations of Credit Risk Financial instruments that potentially subject the Company to credit risk consist principally of cash, cash equivalents, restricted cash, accounts receivable and marketable securities. Cash and restricted cash are maintained in accounts with financial institutions, which, at times may exceed the Federal depository insurance coverage of $0.25 million. The Company has not experienced losses on these accounts and management believes, based upon the quality of the financial institutions, that the credit risk with regard to these deposits is not significant. The Company’s available-for-sale securities consists primarily of investments in commercial paper, U.S. Treasury securities, municipal debt and short-term high credit quality corporate debt securities. Equity securities are comprised of fixed income and equity market index mutual funds. Concentrations of credit risk with respect to receivables exist due to the limited number of select customers with whom the Company has commercial sales arrangements. To mitigate credit risk, the Company performs appropriate evaluation of a prospective customer’s financial condition. At June 30, 2021, one customer comprised 78.5% of the total accounts receivable balance. At December 31, 2020, three customers comprised 73.9% of the total accounts receivable balance. For purposes of assigning a customer to a sale/leaseback transaction completed with a financial institution, the Company considers the end user of the assets to be the ultimate customer. For the three and six months ended June 30, 2021, 81.3% and 77.7%, of total consolidated revenues were associated with three customers, respectively. For the three and six months ended June 30, 2020, 83.9% and 77.9% of total consolidated revenues were associated primarily with two customers, respectively.

Commitments and Contingencies

6 Months Ended

Jun. 30, 2021

19. Commitments and Contingencies

Restricted Cash

In connection with certain of the above noted sale/leaseback agreements, cash of $243.5 million was required to be restricted as security as of June 30, 2021, which restricted cash will be released over the lease term. As of June 30, 2021, the Company also had certain letters of credit backed by restricted cash totaling $143.7 million that are security for the above noted sale/leaseback agreements.

Litigation

Legal matters are defended and handled in the ordinary course of business. Liabilities for loss contingencies arising from claims, assessments, litigation, fines, and penalties and other sources are recorded when it is probable that a liability has been incurred and the amount can be reasonably estimated. Legal costs incurred in connection with loss contingencies are expensed as incurred. The Company has not recorded any accruals related to any legal matters.

Concentrations of Credit Risk

Financial instruments that potentially subject the Company to credit risk consist principally of cash, cash equivalents, restricted cash, accounts receivable and marketable securities. Cash and restricted cash are maintained in accounts with financial institutions, which, at times may exceed the Federal depository insurance coverage of $0.25 million. The Company has not experienced losses on these accounts and management believes, based upon the quality of the financial institutions, that the credit risk with regard to these deposits is not significant. The Company’s available-for-sale securities consists primarily of investments in commercial paper, U.S. Treasury securities, municipal debt and short-term high credit quality corporate debt securities. Equity securities are comprised of fixed income and equity market index mutual funds.

Concentrations of credit risk with respect to receivables exist due to the limited number of select customers with whom the Company has commercial sales arrangements. To mitigate credit risk, the Company performs appropriate evaluation of a prospective customer’s financial condition.

At June 30, 2021, one customer comprised 78.5% of the total accounts receivable balance. At December 31, 2020, three customers comprised 73.9% of the total accounts receivable balance.

For purposes of assigning a customer to a sale/leaseback transaction completed with a financial institution, the Company considers the end user of the assets to be the ultimate customer. For the three and six months ended June 30, 2021, 81.3% and 77.7%, of total consolidated revenues were associated with three customers, respectively. For the three and six months ended June 30, 2020, 83.9% and 77.9% of total consolidated revenues were associated primarily with two customers, respectively.