Lines of Credit and Long-Term Debt - Schedule of Long-Term Debt Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long-term debt	$ 214,574	$ 211,794
Less current portion	564	559
Long-term debt, less current portion	214,010	211,235
Convertible debt
Debt Instrument [Line Items]
Long-term debt	205,829	203,391
Notes payable
Debt Instrument [Line Items]
Long-term debt	4,435	4,551
Royalty-based financing
Debt Instrument [Line Items]
Long-term debt	2,151	2,085
Other
Debt Instrument [Line Items]
Long-term debt	$ 2,159	$ 1,767

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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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