Long-Term Debt - Summary of long term debt (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt	$ 3,494	$ 3,631
Less current portion	(723)	(681)
Long-term debt, Noncurrent	2,771	2,950
Term loan payable to a financial institution; Interest rate option of bank prime or Libor plus 1.4% (3.382% as of June 30, 2018), monthly principal payments of $21,833 through 2021 with a balloon payment of $786,000 due December 1, 2021
Debt Instrument [Line Items]
Long-term debt	1,703	1,835
Term loan payable to a financial institution; Interest rate option of bank prime or Libor plus 1.4% (3.382% as of June 30, 2018), monthly principal payments of $23,810 through December 1, 2021
Debt Instrument [Line Items]
Long-term debt	1,000	1,142
Capital lease obligations; Interest rate fixed for term of each funding based upon the Lender's lease pricing at time of funding. (Interest rate/factor 1.822758% - 1.869304% at time of funding with principal payments made over 60 months)
Debt Instrument [Line Items]
Long-term debt	$ 791	$ 654

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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