Receivables consisted of the following (in thousands):

As of September 30, 2011 and December 31, 2010, unbilled receivables included $13.7 million and $14.9 million, respectively, of incentive fees on certain completed satellite contracts that become due incrementally over periods of up to 15 years, subject to the achievement of performance criteria.  In addition, certain satellite contracts require the company to refund cash to the customer if performance criteria, which cover periods of up to 15 years, are not satisfied.  As of September 30, 2011, the company could be required to refund up to approximately $16.7 million to customers if certain completed satellites were to fail to satisfy performance criteria.  Orbital generally procures insurance policies that the company believes would indemnify the company for satellite incentive fees that are not earned and for performance refund obligations.