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Net Loss per Share (Antidilutive Shares Excluded from Computation of Diluted Shares Outstanding) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Jan. 10, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted weighted shares outstanding	23,341,812	44,024,924
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		$ 2.4
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	3,755,965	3,165,216
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	220,000	200,000
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		21,293,861
Outstanding warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted weighted shares outstanding	19,365,847	19,365,847