Convertible Senior Notes - Schedule of Interest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Amortization of debt issuance costs	$ 2,038	$ 1,977	$ 1,467
Amortization of debt discount	25,824	21,317	15,154
Convertible Senior Notes Due February 2023 | Convertible Debt
Debt Instrument [Line Items]
Contractual interest expense	192	1,566	1,725
Amortization of debt issuance costs	215	999	1,001
Amortization of debt discount	1,218	9,080	9,414
Total	1,625	11,645	12,140
Convertible Senior Notes Due June 2026 | Convertible Debt
Debt Instrument [Line Items]
Contractual interest expense	2,372	2,365	593
Amortization of debt issuance costs	852	821	466
Amortization of debt discount	11,026	10,696	5,740
Total	14,250	13,882	6,799
Convertible Notes Due November 2025 | Convertible Debt
Debt Instrument [Line Items]
Contractual interest expense	436	51	0
Amortization of debt issuance costs	971	157	0
Amortization of debt discount	13,580	1,541	0
Total	$ 14,987	$ 1,749	$ 0