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Line of Credit | 12 Months Ended
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Dec. 31, 2015
Text Block [Abstract] |
Line of Credit |
8. | Line of Credit
In 2013, 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 expires 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, 2015 or 2014.

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