DEBT - Net Carrying Amount (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2020	Feb. 29, 2020	Jun. 30, 2019
Debt Instrument [Line Items]
Effective interest rate	4.31%		4.31%
Convertible Debt
Debt Instrument [Line Items]
Principal	$ 600,000	$ 600,000
Unamortized debt discount	(78,867)
Unamortized issuance costs	(11,710)
Principal, net	509,423
Conversion options	$ 61,604

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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- Definition

Amount of a favorable spread to a debt holder between the amount of debt being converted and the value of the securities received upon conversion. This is an embedded conversion feature of convertible debt issued that is in-the-money at the commitment date.

+ References

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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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.

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Amount, after accumulated amortization, of debt discount.

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- Definition

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

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (b)(3)
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