DEBT - Summary of Net Carrying Amount of Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Convertible Debt
Debt Instrument [Line Items]
Principal amount	$ 300,000	$ 300,000
Unaccreted debt discount	(17,930)	(2,691)
Unamortized debt issuance costs	(5,869)	(4,135)
Debt, net of current portion	276,201	$ 293,174
Line of Credit
Debt Instrument [Line Items]
Principal amount	1,004,700
Unaccreted debt discount	(23,971)
Unamortized debt issuance costs	(22,237)
Debt, net of current portion	$ 958,492

Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

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-Publisher FASB
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+ Details

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- Definition

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

+ References

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