Lines of Credit and Long-Term Debt - Schedule of Long-Term Debt Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term debt	$ 223,313	$ 217,991
Less current portion	32,108	31,670
Long-term debt, less current portion	191,205	186,321
Convertible debt
Debt Instrument [Line Items]
Long-term debt	219,341	213,771
Notes payable
Debt Instrument [Line Items]
Long-term debt	3,868	4,089
Other
Debt Instrument [Line Items]
Long-term debt	$ 104	$ 131

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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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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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