DEBT - Future Payments of Principal and Contractual Interest (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Feb. 29, 2020
Interest
Interest expense, total due	$ 21,826
Convertible Debt
Principal
2020	0
2021	0
2022	0
2023	0
2024	0
2025	600,000
Principal, total due	600,000	$ 600,000
Interest
2020	2,338
2021	4,500
2022	4,500
2023	4,500
2024	4,500
2025	1,488
Total
2020	2,338
2021	4,500
2022	4,500
2023	4,500
2024	4,500
2025	601,488
Principal and interest, total due	$ 621,826

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