(6)	Receivables

The components of receivables were as follows (in thousands):

	June 30, 2014		December 31, 2013
Billed	$	49,015	$	68,474
Unbilled		460,354		515,044
Total	$	509,369	$	583,518

Under the terms of the company's Commercial Resupply Services ("CRS") contract with the National Aeronautics and Space Administration ("NASA"), approximately 25% of the contract value is billable to the customer and collectible only upon the completion of launch and delivery milestones for each of eight CRS contract missions currently scheduled to occur through 2016, of which seven remained as of June 30, 2014. Unbilled receivables at June 30, 2014 and December 31, 2013 included $249 million and $335 million, respectively, pertaining to the CRS contract which will be collected as launches occur. Since the inception of the CRS contract in December 2008 through June 30, 2014, a total of approximately $1.5 billion of revenues have been recognized on the contract, which has a total contract value of approximately $1.9 billion.

As of June 30, 2014 and December 31, 2013, unbilled receivables also included $23.0 million and $9.9 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.

Certain satellite contracts require the company to refund a portion of the contract price to the customer if performance criteria, which cover periods of up to 15 years, are not satisfied. As of June 30, 2014, the company could be required to refund up to $13.2 million to customers if certain completed satellites were to fail to satisfy performance criteria. Orbital generally procures insurance policies under which the company believes it would recover satellite incentive fees that are not earned and performance refund obligations.