Debt - Schedule of Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Debt Instrument [Line Items]
Amortization of debt discount and issuance costs	$ 16,709	$ 9,666	$ 33,264	$ 22,675
Capitalization of interest expense	(1,032)	(1,656)	(1,954)	(3,047)
Total interest expense	17,249	8,446	34,454	20,562
Credit Agreement
Debt Instrument [Line Items]
Interest on debt instruments	135	77	270	216
Convertible Debt \| 2025 Notes
Debt Instrument [Line Items]
Interest on debt instruments	359	359	718	718
Convertible Debt \| 2027 Notes
Debt Instrument [Line Items]
Interest on debt instruments	$ 1,078	$ 0	$ 2,156	$ 0

Increase for accrued, but unpaid interest on the debt instrument for the period.

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Amount of the cost of borrowed funds accounted for as interest expense.

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