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Related party transactions - Additional Information (Details) - USD ($)			12 Months Ended
	Mar. 18, 2021	Jul. 07, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jul. 31, 2020	Jan. 01, 2020
Related Party Transaction [Line Items]
Research and development expense			$ 58,274,000	$ 19,933,000	$ 25,919,000
Related party transaction, terms and manner of settlement			On March 18, 2021, the Company and Carolyn Anderson Short, its co-founder and former Chief of Intellectual Property & Strategy, mutually agreed that Ms. Short would depart the Company on May 31, 2021 following an agreed upon transition period. The Transition Agreement provides for the following severance benefits in exchange for a release of claims by Ms. Short: (i) a lump sum payment equal to eighteen (18) months of Ms. Short’s current base salary, (ii) a payment at her targeted bonus rate for 2021, pro-rated to the separation date, and (iii) accelerated full vesting of her equity awards including 7,747 stock options and 138,461 restricted stock units. The modification of these equity awards resulted in an incremental fair value of $7.0 million which was recognized on a straight-line basis over the transition service period. For the twelve months ended December 31, 2021, the Company recognized $1.0 million related to the lump sum salary payment and target bonus. The Company also recognized non-cash stock-based compensation charges of $9.4 million related to the modified equity awards for the twelve months ended December 31, 2021. No unrecognized stock-based compensation remained as of December 31, 2021. Ms. Short exercised her 7,747 stock options in 2021, therefore there are no remaining options outstanding related to Ms. Short’s transition agreement as of December 31, 2021.
Non-cash stock-based compensation charges			$ 25,117,000	3,022,000	0
Share-based payment arrangement, expense				$ (6,852,000)	$ (6,403,000)
Common Stock, Shares, Issued			35,799,233	32,171,560		6,220,050
Exercised, Number of Shares			7,747
Remaining Options outstanding number				0	14,478,949
E X U M A Biotech Corp And Subsidiary
Related Party Transaction [Line Items]
Share-based payment arrangement, expense					$ 15,000
Expense related To license agreement					10,000
Carolyn Anderson Short
Related Party Transaction [Line Items]
Number of accelerated full vesting equity awards including stock options	7,747
Number of accelerated full vesting equity awards including restricted stock units	138,461
Incremental Fair Value			$ 7,000,000.0
Expense related to Lump Sum Salary Payment and Target Bonus			1,000,000.0
Non-cash stock-based compensation charges			9,400,000
Unrecognized stock-based compensation			$ 0
Exercised, Number of Shares			7,747
Remaining Options outstanding number			0
Private Placement of Common Stock
Related Party Transaction [Line Items]
Common Stock, Shares, Issued			625,000
Net proceeds Issuance Of private placement			$ 17,500,000
Bio Duro
Related Party Transaction [Line Items]
Research and development expense					1,900,000
Biotech Investment Group II LLC
Related Party Transaction [Line Items]
Interest expense, related party				$ 42,000	20,000
Loan amount under the terms					500,000
Jay Short And Carolyn Anderson Short
Related Party Transaction [Line Items]
Debt instrument settled date			2020-07
Jay Short And Carolyn Anderson Short \| 2019 Notes
Related Party Transaction [Line Items]
Debt instrument, face amount			$ 1,000,000.0
Interest expense, related party				100,000
Jay Short And Carolyn Anderson Short \| 2020 Notes
Related Party Transaction [Line Items]
Debt instrument, face amount			$ 500,000
Interest expense, related party					$ 32,000
Inversagen L L C
Related Party Transaction [Line Items]
Royalty Expense		$ 0
Options grants related to royalty payment, Period			10 years
Assets or liabilities associated with related party variable interest			$ 0	0
Himalaya Therapeutics S E Z C
Related Party Transaction [Line Items]
Royalty Expense			0
Assets or liabilities associated with related party variable interest				0
Bio Atla Holdings L L C
Related Party Transaction [Line Items]
Assets or liabilities associated with related party variable interest			0	0
Options grants related to royalty payments, Period		10 years
Equity Interest In Related Party							50.00%
Himalaya Parent L L C
Related Party Transaction [Line Items]
Non-cash stock-based compensation charges			$ 0	$ 700,000