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Collaboration and License Agreements - Amgen, Inc (Details) $ in Thousands		3 Months Ended
	Sep. 28, 2016 USD ($) agreement	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2022 USD ($)	Jul. 31, 2020 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues			$ 62,546	$ 27,439
Contract liabilities			66,281		$ 74,099
Amgen \| Subsequent Event
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront milestone payment received		$ 25,000
Amgen \| Collaboration and License agreements
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of agreements \| agreement	2
Amgen \| Olpasiran Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment	$ 35,000
Proceeds from the issuance of common stock	21,500
Milestone payments	$ 30,000
Amgen \| Olpasiran Agreement \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Additional remaining development regulatory and sales milestones payments			375,000
Amgen \| Olpasiran and ARO-AMG1 Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payments						$ 20,000
Revenues			25,000	$ 0
Contract assets			25,000
Contract liabilities			$ 0