Significant Agreements - Neurocrine Collaboration Agreements (Details) $ / shares in Units, $ in Thousands		1 Months Ended			3 Months Ended				12 Months Ended
	Jan. 08, 2023 USD ($) $ / shares shares	Feb. 28, 2023 USD ($) item Program $ / shares shares	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($) Program item $ / shares shares	Dec. 31, 2023 USD ($) item	Mar. 31, 2023 item	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2023 USD ($) item shares	Dec. 31, 2022 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Purchase of common stock									$ 31,121
Allocation of Transaction Price
Deferred revenue, current					$ 42,881		$ 59,377		42,881	$ 59,377
Deferred revenue, non-current					32,359		6,450		32,359	6,450
Related party collaboration receivable					3,341		257		$ 3,341	257
Neurocrine Collaborative Agreement 2019 | FA Program
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage of profit or loss under co-co option				40.00%
Neurocrine Collaborative Agreement 2019 | Neurocrine
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of discovery programs				2					92,382
Programs added later | item				2
Discovery programs under development | item				2
Number of targets | item				8
Upfront payment				$ 115,000					$ 115,000
Purchase of common stock, shares | shares				4,179,728					4,179,728
Purchase of common stock				$ 50,000					$ 5,000
Price per share | $ / shares				$ 11.9625
Aggregate maximum milestone payments to be received from collaborative partner				$ 170,000
Estimated cost reimbursement					83,300		$ 81,700	$ 80,000	431,100
Termination period				10 years
Period of advance notice for termination prior to first commercial sale				180 days
Period of advance notice for termination after first commercial sale				1 year
Discount related to equity investment									27,600
Equity investment					50,000				50,000
Allocation of Transaction Price
Allocation of variable consideration					83,251				83,251
Allocation of fixed consideration					92,400				92,400
Cumulative catch up of revenue recognized									900
Reimbursement costs expected to be received									1,600
Costs to obtain collaboration agreement					800				800
Consideration received			$ 5,000
Deferred revenue					6,100				6,100
Neurocrine Collaborative Agreement 2019 | Neurocrine | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage of reduction in royalty payments				50.00%
Neurocrine Collaborative Agreement 2019 | Neurocrine | VY-AADC
Allocation of Transaction Price
Allocation of variable consideration					53,863				53,863
Allocation of fixed consideration					49,045				49,045
Neurocrine Collaborative Agreement 2019 | Neurocrine | FA Program
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage of profit or loss under co-co option				60.00%
Allocation of Transaction Price
Allocation of variable consideration					20,309				20,309
Allocation of fixed consideration					20,647				20,647
Neurocrine Collaborative Agreement 2019 | Neurocrine | Discovery and FA Programs
Allocation of Transaction Price
Allocation of fixed consideration					42,200				42,200
Neurocrine Collaborative Agreement 2019 | Neurocrine | Discovery program 1
Allocation of Transaction Price
Allocation of variable consideration					4,286				4,286
Allocation of fixed consideration					14,443				14,443
Neurocrine Collaborative Agreement 2019 | Neurocrine | Discovery program 2
Allocation of Transaction Price
Allocation of variable consideration					4,793				4,793
Allocation of fixed consideration					$ 8,247				8,247
Neurocrine Collaborative Agreement 2019 | Neurocrine | Active programs
Allocation of Transaction Price
Revenue recognized									$ 9,800	$ 900
Neurocrine Collaborative Agreement 2019 | Neurocrine | Development and regulatory milestones | FA Program
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Aggregate maximum milestone payments to be received from collaborative partner				$ 195,000
Neurocrine Collaborative Agreement 2019 | Neurocrine | Development and regulatory milestones | Discovery program 1
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Aggregate maximum milestone payments to be received from collaborative partner				130,000
Neurocrine Collaborative Agreement 2019 | Neurocrine | Commercial milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Per milestone, maximum milestone payments to be received from collaborative partner				275,000
Aggregate maximum milestone payments to be received from collaborative partner				$ 1,100,000
Neurocrine Collaborative Agreement 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage of profit or loss under co-co option	50.00%
Percentage of development costs incurred	50.00%
Neurocrine Collaborative Agreement 2023 | Development milestone | Minimum
Allocation of Transaction Price
Number of countries received regulatory approval | item					1				1
Neurocrine Collaborative Agreement 2023 | Neurocrine
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of collaboration programs | item									3
Number of discovery programs | item						3			3
Number of development and commercialization licenses | item									2
Percentage of profit or loss under co-co option	50.00%
Percentage of development costs incurred	50.00%
Upfront payment		$ 136,000
Purchase of common stock, shares | shares	4,395,588	4,395,588
Purchase of common stock	$ 39,000	$ 39,000
Price per share | $ / shares	$ 8.88	$ 8.88
Termination period		10 years
Amount of premium		$ 7,900
Period of advance notice for termination prior to first commercial sale		180 days
Period of advance notice for termination after first commercial sale		1 year
Period of advance notice for termination after complete readout of clinical trial		30 days
Discount related to equity investment		$ 39,000
Allocation of Transaction Price
Allocation of variable consideration					$ 11,259				$ 11,259
Allocation of fixed consideration		$ 143,900			143,880				143,880
Cumulative catch up of revenue recognized									69,100
Reimbursement costs expected to be received									11,300
Costs to obtain collaboration agreement					400				400
Deferred revenue, current					38,400				38,400
Deferred revenue, non-current					30,700				30,700
Related party collaboration receivable					1,800				1,800
Neurocrine Collaborative Agreement 2023 | Neurocrine | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage of reduction in royalty payments		50.00%
Neurocrine Collaborative Agreement 2023 | Neurocrine | GBA1
Allocation of Transaction Price
Allocation of variable consideration					5,920				5,920
Allocation of fixed consideration					69,459				69,459
Revenue recognized									69,500
Neurocrine Collaborative Agreement 2023 | Neurocrine | Discovery program 1
Allocation of Transaction Price
Allocation of variable consideration					3,779				3,779
Allocation of fixed consideration					24,807				24,807
Neurocrine Collaborative Agreement 2023 | Neurocrine | Discovery program 2
Allocation of Transaction Price
Allocation of variable consideration					780				780
Allocation of fixed consideration					24,807				24,807
Neurocrine Collaborative Agreement 2023 | Neurocrine | Discovery program 3
Allocation of Transaction Price
Allocation of variable consideration					780				780
Allocation of fixed consideration					$ 24,807				$ 24,807
Neurocrine Collaborative Agreement 2023 | Neurocrine | Discovery Programs 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of discovery programs | item									3
Allocation of Transaction Price
Revenue recognized									$ 5,500
Neurocrine Collaborative Agreement 2023 | Neurocrine | Development milestone
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Discovery programs under development | Program		3
Neurocrine Collaborative Agreement 2023 | Neurocrine | Development milestone | GBA1
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Aggregate maximum milestone payments to be received from collaborative partner		$ 985,000
Neurocrine Collaborative Agreement 2023 | Neurocrine | Development milestone | Discovery Programs 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Aggregate maximum milestone payments to be received from collaborative partner		175,000
Neurocrine Collaborative Agreement 2023 | Neurocrine | Commercial milestone | GBA1 | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Per milestone, maximum milestone payments to be received from collaborative partner		$ 950,000
Allocation of Transaction Price
Number of products | item		2
Neurocrine Collaborative Agreement 2023 | Neurocrine | Commercial milestone | Discovery Programs 2023
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Per milestone, maximum milestone payments to be received from collaborative partner		$ 275,000
Allocation of Transaction Price
Number of products | item		1
Neurocrine Collaborative Agreement 2023 | Neurocrine | Research and development milestone | GBA1
Allocation of Transaction Price
Revenue recognized									$ 5,800