18. Concentrations

Concentrations of Credit and Business Risk

Financial instruments that potentially subject us to a concentration of credit risk consist of cash and cash equivalents and accounts receivable.

At December 31, 2019, our cash and cash equivalents were maintained primarily with two major U.S. financial institutions and three foreign banks. We also maintained cash balances with three internet payment processors. Deposits with these institutions at times exceed the federally insured limits, which potentially subjects us to concentration of credit risk. Historically, we have not experienced any losses related to these balances and believe that there is minimal risk of expected future losses. However, there can be no assurance that there will not be losses on these deposits.

A substantial portion of our advertising revenue is generated from multiple arrangements with one customer. Customers comprising more than 10% of consolidated revenue were as follows:

Customers comprising more than 10% of the consolidated accounts receivable balance were as follows:

Year ended December 31,

Google Inc.