Income Taxes - Schedule of Significant Components of Deferred Tax Assets for Federal and State Income Taxes (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Federal and state net operating loss carryforwards	$ 1	$ 24
Research and development credits carryforwards	26	22
Stock-based compensation	21	16
Depreciation and amortization	3	6
Deferred revenue	66	19
Lease liability	26	25
Capitalized research and development costs	109	53
Other	1	7
Total deferred tax assets	253	172
Deferred tax liabilities:
Right-of-use assets	(20)	(22)
Total deferred tax liabilities	(20)	(22)
Less valuation allowance	(233)	(150)
Net deferred tax assets (liabilities)	$ 0	$ 0