DEBT - Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt
Total debt	$ 433,484	$ 447,234
Unamortized debt discount and issuance costs	(56,364)	(64,379)
Net long-term debt	377,120	382,855
Term B Loan \| Senior secured term loans
Debt
Total debt	0	13,750
2023 Notes \| Convertible subordinated notes
Debt
Total debt	240,984	240,984
2025 Notes \| Convertible senior notes
Debt
Total debt	192,500	192,500
Unamortized debt discount and issuance costs	$ (54,597)	$ (61,766)

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 of unamortized debt discount (premium) and debt issuance costs.

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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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