Debt - Schedule of Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Debt Instrument [Line Items]
Amortization of debt discount and issuance costs	$ 17,504	$ 16,866	$ 52,029	$ 50,130
Capitalization of interest expense	(937)	(1,119)	(2,745)	(3,073)
Total interest expense	18,144	17,324	54,015	51,778
Credit Agreement
Debt Instrument [Line Items]
Interest on debt instruments	141	139	421	409
Convertible Debt \| 2025 Notes
Debt Instrument [Line Items]
Interest on debt instruments	358	360	1,076	1,078
Convertible Debt \| 2027 Notes
Debt Instrument [Line Items]
Interest on debt instruments	$ 1,078	$ 1,078	$ 3,234	$ 3,234

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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