Line of Credit	3 Months Ended
Mar. 31, 2018
Debt Disclosure [Abstract]
Line of Credit	Line of Credit The Company has a $10.0 million revolving line of credit with a domestic bank. At both March 31, 2018 and December 31, 2017, there were no borrowings under the line. Under the terms of the line of credit, available borrowings are reduced by outstanding letters of credit. As of March 31, 2018, the Company had letters of credit outstanding of $2.7 million under the facility, and available borrowing of $7.3 million. The line is secured by substantially all of the assets of the Company, and bears interest at varying rates (currently LIBOR plus 1.25% or Prime less 0.50%). The line of credit matures on December 31, 2018, and requires monthly payments of interest only. The Company’s agreement with the bank requires it to comply with a maximum funded debt to earnings before interest, taxes, depreciation and amortization ("EBITDA") ratio, as defined, of no greater than 2.00 to 1.00 based upon a trailing twelve-month period. At March 31, 2018, the Company’s funded debt to EBITDA ratio was 0.002 to 1.00.

Line of Credit

3 Months Ended

Mar. 31, 2018

The Company has a $10.0 million revolving line of credit with a domestic bank. At both March 31, 2018 and December 31, 2017, there were no borrowings under the line. Under the terms of the line of credit, available borrowings are reduced by outstanding letters of credit. As of March 31, 2018, the Company had letters of credit outstanding of $2.7 million under the facility, and available borrowing of $7.3 million. The line is secured by substantially all of the assets of the Company, and bears interest at varying rates (currently LIBOR plus 1.25% or Prime less 0.50%). The line of credit matures on December 31, 2018, and requires monthly payments of interest only. The Company’s agreement with the bank requires it to comply with a maximum funded debt to earnings before interest, taxes, depreciation and amortization ("EBITDA") ratio, as defined, of no greater than 2.00 to 1.00 based upon a trailing twelve-month period. At March 31, 2018, the Company’s funded debt to EBITDA ratio was 0.002 to 1.00.