Summary of Significant Accounting Policies - Liquidity Matters (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 31, 2024
Policies
Net loss	$ 85,091	$ 66,936
Accumulated deficit	2,861,113		$ 2,776,022
Cash, cash equivalents and restricted cash	1,087,932	$ 973,768	1,076,140	$ 945,587
Outstanding balance	80,305		$ 80,323
Collateral amount	150,000
Remaining borrowing capacity	20,000
UBS Credit Line
Policies
Outstanding balance	$ 80,300