Leases - Narrative (Details) $ in Thousands	1 Months Ended											3 Months Ended		9 Months Ended
	Aug. 31, 2026 USD ($)	May 31, 2026 USD ($) ft²	Jan. 31, 2026 USD ($) ft²	Dec. 31, 2025 USD ($) ft²	Aug. 31, 2025 USD ($) ft²	Mar. 31, 2025 USD ($) ft²	Jan. 31, 2025 USD ($) ft²	Sep. 30, 2023 USD ($) ft²	Dec. 31, 2021 lease	Nov. 30, 2020 USD ($) ft²	Oct. 31, 2016 ft² lease	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Jul. 31, 2026 ft²	Jul. 31, 2024	Jan. 31, 2023	Sep. 30, 2022 ft²	Feb. 28, 2022 ft²	Jan. 31, 2021	Sep. 30, 2015 ft²
Lessee, Lease, Description [Line Items]
Noncash operating activities related to right-of-use assets														$ 34,600	$ 19,800
Weighted average remaining lease term (in years)												6 years 10 months 9 days		6 years 10 months 9 days
Weighted average discount rate (as a percent)												6.60%		6.60%
Lease expense												$ 7,100	$ 5,500	$ 20,400	14,800
Operating lease payments														$ 18,300	$ 14,200
Laboratory and Office Spaces
Lessee, Lease, Description [Line Items]
Lease space (area) | ft²		19,652		15,485	45,800			16,319		11,395	136,300								65,222	32,500		94,000
Term of lease (in months)		5 years						60 months		36 months												132 months
Number of office space locations | lease									2		2
Annual lease payment		$ 500			$ 700		$ 9,700	$ 900		$ 900
Renewal term of lease (in months)																	60 months	3 years			48 months
Laboratory and Office Spaces | Austin, TX Additional Premises Lease
Lessee, Lease, Description [Line Items]
Lease space (area) | ft²						57,100
Annual lease payment						$ 900
Laboratory and Office Spaces | First Space San Carlos, California
Lessee, Lease, Description [Line Items]
Lease space (area) | ft²											88,400
Laboratory and Office Spaces | Second Space San Carlos, California
Lessee, Lease, Description [Line Items]
Lease space (area) | ft²											47,900
Laboratory and Office Spaces | Additional Space San Carlos, California
Lessee, Lease, Description [Line Items]
Lease space (area) | ft²			63,000				40,700									15,600
Term of lease (in months)			10 years													10 years
Annual lease payment	$ 400		$ 4,400				$ 1,500
Laboratory and Office Spaces | South San Francisco
Lessee, Lease, Description [Line Items]
Lease space (area) | ft²						19,715
Term of lease (in months)						7 years
Annual lease payment						$ 400
Laboratory and Office Spaces | Minimum
Lessee, Lease, Description [Line Items]
Term of lease (in months)												1 year		1 year
Laboratory and Office Spaces | Maximum
Lessee, Lease, Description [Line Items]
Term of lease (in months)												5 years		5 years
Austin, TX Additional Premises Lease
Lessee, Lease, Description [Line Items]
Lease space (area) | ft²				28,468
Annual lease payment				$ 400
Boulder, CO Lease
Lessee, Lease, Description [Line Items]
Lease space (area) | ft²				25,718
Annual lease payment				$ 1,500