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Net Loss per Share (Antidilutive Shares Excluded from Computation of Diluted Shares Outstanding) (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2025	Dec. 31, 2024	Jan. 10, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted weighted shares outstanding	39,644,802	23,341,812
Innoviva Strategic Opportunities LLC \| Secured term loan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Convertible loan principal amount	$ 30.0
Accrued and unpaid interest	$ 6.0
Interest rate (as a percent)	8.00%		8.00%
Price per share	$ 1.52		$ 1.52
Outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted weighted shares outstanding	5,094,273	3,755,965
Unvested restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted weighted shares outstanding	202,500	220,000
Shares issuable upon the conversion of the Convertible Loan
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted weighted shares outstanding	23,692,982
Outstanding warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted weighted shares outstanding	10,655,047	19,365,847