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Line of Credit | 12 Months Ended
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Dec. 31, 2014
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Line of Credit |
8. | Line of Credit
In October 2007, the Company entered into an agreement providing for a line of credit in the maximum amount of $20.0 million with Frost Bank, NA. The agreement expired in October 2010. The Company renewed this agreement in the fourth quarter 2010 for an additional three years to mature in December 2013. In the fourth quarter 2013, the Company renewed this agreement for an additional three years to mature in December 2016. Under the agreement, advances may be made either in the form of loans or letters of credit. Borrowings under the agreement accrue at interest rates based upon prime rate or LIBOR. Under the agreement, the Company will pay a fee of 0.25% on the unused portion of the loan in arrears quarterly for a fee of $50,000 annually, assuming the line of credit is not used during the calendar year. The line of credit is unsecured. No borrowings or letters of credit were outstanding under the line of credit arrangement at December 31, 2014 or 2013.

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