Debt - Schedule of Long-Term Debt Instruments (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt, gross	$ 29,489,000	$ 29,535,000
Total long-term debt	155,000	170,000
Total long-term debt less debt issuance costs	29,334,000	29,365,000
Less amounts classified as current	10,585,000	9,928,000
Long-term debt, excluding current portion	18,749,000	19,437,000
Debt issuance costs, current	60
Debt issuance costs, noncurrent		95
Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	2,551,000	2,597,000
2018 Term Notes \| Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	21,938,000	21,938,000
Line of Credit \| Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	$ 5,000,000	$ 5,000,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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