Debt Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	$ 29,535
Debt issuance costs	0	170
Total long-term debt less debt issuance costs	0	29,365
Current portion of long-term debt	0	9,928
Long-term debt, excluding current portion	0	19,437
Debt issuance costs, current		60
Debt issuance costs, noncurrent		110
Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	0	2,597
Term Loan \| Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	0	21,938
Line of Credit \| Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	$ 5,000

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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Amount, after accumulated amortization, of debt issuance costs classified as current. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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

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