Debt and Line of Credit - Schedule of Long-Term debt (Details) - USD ($)	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt	$ 29,535,000		$ 47,054,000
Debt issuance costs	170,000		0
Total long-term debt	29,365,000		47,054,000
Less amounts classified as current	9,928,000		2,482,000
Long-term debt, excluding current portion	19,437,000	$ 44,572,000	44,572,000
Debt issuance costs, current	60
Debt issuance costs, long-term	110
Mortgage loan
Debt Instrument [Line Items]
Long-term debt	2,597,000		2,779,000
2014 Term Notes \| Line of Credit
Debt Instrument [Line Items]
Long-term debt	0		44,275,000
2018 Term Notes \| Line of Credit
Debt Instrument [Line Items]
Long-term debt	21,938,000		0
Line of Credit \| Line of Credit
Debt Instrument [Line Items]
Long-term debt	$ 5,000,000		$ 0

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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