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License, Collaboration, and Success Payment Agreements - Narrative (Details) |  | 1 Months Ended | 3 Months Ended | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 01, 2022 USD ($) | Jun. 30, 2020 USD ($) $ / shares shares | May 31, 2019 USD ($) $ / shares shares | Jun. 30, 2023 USD ($) | Jun. 30, 2022 USD ($) | Dec. 31, 2021 USD ($) | Jun. 30, 2023 USD ($) | Jun. 30, 2022 USD ($) | Dec. 31, 2022 USD ($) | Oct. 31, 2020 USD ($) $ / shares | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) $ / shares
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  | $ 47,471,000 | $ 43,719,000 |  | $ 92,101,000 | $ 79,549,000 |  |  |  |
Impairment of other investments |  |  |  | 2,923,000 | 0 |  | 12,923,000 | 0 |  |  |  |
Settled Litigation |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Ownership of fully diluted shares (as a percent) | 80.00% |  |  |  |  |  |  |  |  |  |  |
PACT |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Impairment of other investments |  |  |  |  |  | $ 36,400,000 |  |  |  |  |  |
Series A Convertible Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Convertible preferred stock, par value (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  | $ 1.83 |  | $ 1.83
Fred Hutch | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Annual license maintenance payments |  |  |  |  |  |  |  |  |  |  |  | $ 50,000
Aggregate research payments due |  |  |  |  |  |  |  |  |  |  |  | $ 12,000,000
Term of collaborative arrangement for research |  |  |  |  |  |  |  |  |  |  |  | 6 years
Research and development expense |  |  |  | 100,000 | 500,000 |  | 400,000 | 1,000,000 |  |  |  |
Aggregate success payment(s) (in millions) |  |  |  | 0 |  |  | 0 |  |  |  |  |
Term of success payment agreement |  |  |  |  |  |  |  |  |  |  |  | 9 years
Trigger period from IPO date |  |  |  |  |  |  |  |  |  |  |  | 1 year
Trigger period thereafter |  |  |  |  |  |  |  |  |  |  |  | 2 years
Fair value of potential success payments due |  |  |  | 1,900,000 |  |  | 1,900,000 |  | $ 2,500,000 |  |  |
Success payment expense (gain) |  |  |  | 500,000 | 2,200,000 |  | (600,000) | (600,000) |  |  |  |
Fred Hutch | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Minimum |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Multiple of initial equity value at issuance |  |  |  |  |  |  |  |  |  |  |  | 10
Aggregate success payment(s) (in millions) |  |  |  |  |  |  |  |  |  |  |  | $ 10,000,000
Per share common stock price required for payment (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  | $ 18.29
Fred Hutch | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Multiple of initial equity value at issuance |  |  |  |  |  |  |  |  |  |  |  | 50
Aggregate success payment(s) (in millions) |  |  |  |  |  |  |  |  |  |  |  | $ 200,000,000
Per share common stock price required for payment (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  | $ 91.44
Stanford | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Annual license maintenance payments |  |  |  |  |  |  |  |  |  |  | $ 50,000 |
Aggregate research payments due |  |  |  |  |  |  |  |  |  | $ 12,000,000 |  |
Term of collaborative arrangement for research |  |  |  |  |  |  |  |  |  | 4 years |  |
Research and development expense |  |  |  | 700,000 | 800,000 |  | 1,500,000 | 1,500,000 |  |  |  |
Aggregate success payment(s) (in millions) |  |  |  | 0 |  |  | 0 |  |  |  |  |
Term of success payment agreement |  |  |  |  |  |  |  |  |  | 9 years |  |
Trigger period from IPO date |  |  |  |  |  |  |  |  |  | 1 year |  |
Trigger period thereafter |  |  |  |  |  |  |  |  |  | 2 years |  |
Fair value of potential success payments due |  |  |  | 2,700,000 |  |  | 2,700,000 |  | 3,300,000 |  |  |
Success payment expense (gain) |  |  |  | 600,000 | 1,400,000 |  | 0 | 400,000 |  |  |  |
Success payment liability |  |  |  | 1,900,000 |  |  | 1,900,000 |  | 1,900,000 |  |  |
Stanford | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | License |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Potential milestone payments due |  |  |  |  |  |  |  |  |  |  | 2,500,000 |
Stanford | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Minimum |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Multiple of initial equity value at issuance |  |  |  |  |  |  |  |  |  | 10 |  |
Aggregate success payment(s) (in millions) |  |  |  |  |  |  |  |  |  | $ 10,000,000 |  |
Per share common stock price required for payment (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  | $ 18.29 |  |
Stanford | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Multiple of initial equity value at issuance |  |  |  |  |  |  |  |  |  | 50 |  |
Aggregate success payment(s) (in millions) |  |  |  |  |  |  |  |  |  | $ 200,000,000 |  |
Per share common stock price required for payment (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  | $ 91.44 |  |
Stanford | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Maximum | License |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Potential milestone payments due |  |  |  |  |  |  |  |  |  |  | $ 3,700,000 |
GSK | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Contract liabilities |  |  |  | 0 |  |  | 0 |  | 0 |  |  |
Revenue recognized |  |  |  | 0 | 35,700,000 |  | 0 | 36,300,000 |  |  |  |
GSK | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Adjustment To Revenue Related To Change In Estimate |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenue recognized |  |  |  |  | $ 35,300,000 |  |  | $ 35,300,000 |  |  |  |
GSK | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | License |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Contract liabilities |  |  | $ 45,000,000 | 0 |  |  | 0 |  | 0 |  |  |
Stock purchase agreement portion of transaction price |  |  | 58,600,000 |  |  |  |  |  |  |  |  |
Transaction price |  |  | $ 103,600,000 |  |  |  |  |  |  |  |  |
Contract assets |  |  |  | $ 0 |  |  | $ 0 |  | $ 0 |  |  |
GSK | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | License | Series AA Convertible Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Stock sold under stock purchase program (in shares) | shares |  |  | 30,253,189 |  |  |  |  |  |  |  |  |
Price per share of stock sold under stock purchase program (in dollars per share) | $ / shares |  |  | $ 6.78 |  |  |  |  |  |  |  |  |
Fair value per share of stock sold under stock purchase program (in dollars per share) | $ / shares |  |  | $ 4.84 |  |  |  |  |  |  |  |  |
PACT |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gain on other investments | $ 2,900,000 |  |  |  |  |  |  |  |  |  |  |
PACT | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Upfront payment |  | $ 50,000,000 |  |  |  |  |  |  |  |  |  |
Stock purchase agreement, stock purchased (in shares) | shares |  | 17,806,901 |  |  |  |  |  |  |  |  |  |
Stock purchase agreement, purchase price per share (in dollars per share) | $ / shares |  | $ 2.81 |  |  |  |  |  |  |  |  |  |
Stock purchase agreement, fair value per share (in dollars per share) | $ / shares |  | $ 2.05 |  |  |  |  |  |  |  |  |  |
Additional purchase price consideration |  | $ 13,600,000 |  |  |  |  |  |  |  |  |  |
Total upfront payment paid |  | 63,600,000 |  |  |  |  |  |  |  |  |  |
PACT | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement | Other Investment |  |  |  |  |  |  |  |  |  |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Strategic equity investment |  | $ 36,400,000 |  |  |  |  |  |  |  |  |  |

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