2. CONTRACTS RECEIVABLE AND RETAINAGE

The principal customers of the Company include major and large independent oil and gas companies and their contractors and marine vessel operators and their contractors. Of our contracts receivable balance at December 31, 2014, $47.1 million, or 58.5%, is for three customers.

During the fourth quarter of 2014, the Company included an allowance for bad debt in the amount of $3.6 million in connection with negotiations of an outstanding contract receivable balance with a customer related to a deepwater hull project that was completed during the first quarter of 2014.

At December 31, 2013, the Company included an allowance for bad debt in the amount of $0.9 million in connection with a vessel upgrade and outfitting project. The Company collected $0.6 million of this balance as part of the final settlement during the fourth quarter 2014.