Debt - Long-Term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Less: unamortized debt issuance costs	$ (116,352)	$ (7,238)
Total debt	268,849	247,260
Less: current portion of long-term debt	(625)	(640)
Long-term debt	268,224	246,620
Convertible senior notes
Debt Instrument [Line Items]
Long-term debt	380,000	0
Senior secured term loan facility
Debt Instrument [Line Items]
Long-term debt	0	250,000
Deferred government grant obligations
Debt Instrument [Line Items]
Long-term debt	3,500	3,500
Other borrowings
Debt Instrument [Line Items]
Long-term debt	$ 1,701	$ 998

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. 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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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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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