Convertible Senior Notes - Extinguishment (Details) - USD ($) $ in Thousands, shares in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Convertible Senior Notes
Loss on extinguishment of debt	$ 11,459	$ 0
2025 Notes
Convertible Senior Notes
Shares issued for exchange of debt	1.1
Loss on extinguishment of debt	$ 8,100

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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