Long-Term Debt - Summary of long term debt (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt	$ 2,952	$ 3,133
Less current portion	(723)	(723)
Long-term debt, Noncurrent	2,229	2,410
Term loan payable to a financial institution; Interest rate option of bank prime or Libor plus 1.4% (3.909% as of March 31, 2019), 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	1,507	1,572
Term loan payable to a financial institution; Interest rate option of bank prime or Libor plus 1.4% (3.909% as of March 31, 2019), monthly principal payments of $23,810 through December 1, 2021
Debt Instrument [Line Items]
Long-term debt	786	857
Lease line of credit for equipment; 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), monthly principle payments of $12,675 through April 10, 2023
Debt Instrument [Line Items]
Long-term debt	$ 659	$ 704

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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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