Income Taxes - Schedule of Reconciliation of the U.S. Federal Statutory Income Tax Rate to Effective Income Tax Rate (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Amount
U.S. Federal statutory tax rate	$ (16.9)	$ (41.6)	$ (76.4)
State and local income taxes, net of federal income tax effect	0.1	4.6	2.1
Research and development tax credit	(6.8)	(9.1)	(28.0)
Changes in valuation allowance	16.6	43.8	98.2
Stock compensation	7.5	2.1	4.5
Other	(0.2)	0.8	0.5
Income tax expense	$ 0.3	$ 0.6	$ 0.9
Percent
U.S. Federal statutory tax rate	21.00%	21.00%	21.00%
State and local income taxes, net of federal income tax effect	(0.10%)	(2.30%)	(0.60%)
Research and development tax credit	8.50%	4.60%	7.60%
Changes in valuation allowance	(20.60%)	(22.10%)	(26.90%)
Research and development tax credit	(9.30%)	(1.10%)	(1.20%)
Other	0.10%	(0.40%)	(0.20%)
Effective tax rate	(0.40%)	(0.30%)	(0.30%)

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 231
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-231