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Net Loss per Share (Antidilutive Shares Excluded from Computation of Diluted Shares Outstanding) (Details) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 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	46,026,192	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	$ 4.2
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	3,934,731	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	230,000	200,000
Shares issuable upon the conversion of convertible debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted weighted shares outstanding	22,495,614	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