Summary of Significant Accounting Policies - Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Convertible notes, net of current portion	$ 551,598	$ 557,468
Additional paid-in capital	1,064,358	1,024,577
Accumulated deficit	493,933	$ 381,187
Minimum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Convertible notes, net of current portion	113,000
Additional paid-in capital	155,000
Accumulated deficit	(41,000)
Maximum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Convertible notes, net of current portion	116,000
Additional paid-in capital	158,000
Accumulated deficit	$ (44,000)