Debt - Schedule of Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Amortization of debt discount and issuance costs	$ 16,866	$ 12,982	$ 50,130	$ 35,657
Capitalization of interest expense	(1,119)	(1,849)	(3,073)	(4,896)
Total interest expense	17,324	12,127	51,778	32,689
Credit Agreement
Debt Instrument [Line Items]
Interest on debt instruments	139	156	409	372
Convertible Debt \| 2025 Notes
Debt Instrument [Line Items]
Interest on debt instruments	360	359	1,078	1,077
Convertible Debt \| 2027 Notes
Debt Instrument [Line Items]
Interest on debt instruments	$ 1,078	$ 479	$ 3,234	$ 479

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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