Debt Instrument, Additional Committed Amount

No definition available.

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Namespace Prefix:	rcus_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Instrument, Face Amount, Contingently Available

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Milestone Achievement Period

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

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Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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- Definition

The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

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Long-Term Debt - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2024	Dec. 31, 2025	Jun. 30, 2025
Debt Instrument [Line Items]
Interest expense, debt	$ 3	$ 2
Debt instrument, interest rate, effective percentage		13.39%		12.85%	13.08%
Hercules Agreement \| Secured Debt
Debt Instrument [Line Items]
Debt instrument, face amount			$ 250
Proceeds from issuance of secured debt			50
Debt Instrument, additional committed amount					$ 50
Debt instrument, face amount, contingently available			150
Hercules Agreement \| Secured Debt \| Tranche One
Debt Instrument [Line Items]
Debt instrument, face amount, contingently available			$ 50
Debt instrument, milestone achievement period			90 days
Hercules Agreement \| Secured Debt \| Tranche Two
Debt Instrument [Line Items]
Debt Instrument, additional committed amount			$ 50
Debt instrument, face amount, contingently available			$ 50
Debt instrument, milestone achievement period			90 days