Lines of Credit and Long-Term Debt - Components of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt	$ 217,991	$ 211,695
Less current portion	31,670	479
Long-term debt, less current portion	186,321	211,216
Convertible debt
Debt Instrument [Line Items]
Long-term debt	213,771	203,391
Notes payable
Debt Instrument [Line Items]
Long-term debt	4,089	4,551
Other
Debt Instrument [Line Items]
Long-term debt	$ 131	$ 3,753

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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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