DEBT - Convertible Subordinated Notes (Details)			1 Months Ended		3 Months Ended	12 Months Ended
	Apr. 18, 2022 USD ($)	Mar. 07, 2022 USD ($)	Jul. 31, 2014 $ / shares $ / Item	Jan. 31, 2013 USD ($) Item $ / shares $ / Item shares	Mar. 31, 2022 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2016 USD ($)
Debt
Payment for repurchase of debt instrument						$ 96,204,000	$ 165,131,000	$ 0
Accrued interest payable						3,422,000	4,359,000
Loss on extinguishment of debt						0	(20,662,000)	0
Debt discount and issuance costs, net						(7,266,000)	(9,331,000)
2023 Notes
Debt
Convertible notes Face Value						96,200,000
2023 Notes | Convertible subordinated notes
Debt
Convertible notes Face Value				$ 287,500,000
Debt Instrument, annual interest rate				2.125%
Portion of debt retired, face value		$ 144,800,000			$ 144,800,000				$ 14,100,000
Portion of debt retired, carrying value		144,500,000							$ 13,900,000
Payment for repurchase of debt instrument		$ 165,600,000			$ 165,600,000
Percentage of notes repurchased		60.00%
Accrued interest payable		$ 400,000
Unamortized debt issuance cost		300,000
Loss on extinguishment of debt		20,700,000
Principal	$ 96,200,000	96,200,000				0	96,204,000
Debt discount and issuance costs, net		$ (200,000)					(11,000)
Net Carrying Amount							96,193,000
Interest expense
Contractual interest expense						85,000	2,617,000	5,121,000
Amortization of debt issuance costs						11,000	302,000	580,000
Total interest and amortization expense						$ 96,000	$ 2,919,000	$ 5,701,000
2023 Notes | Convertible subordinated notes | Privately-negotiated capped call option
Debt
Number of derivative instruments purchased | Item				2
Strike price for the underlying number of shares (in dollars per share) | $ / shares			$ 19.77	$ 27.79
Cap price for the underlying number of shares (in dollars per share) | $ / Item			27.04	38
2023 Notes | Convertible subordinated notes | Stock prices below $27.79 per share | Minimum
Debt
Net shares settlement payable to the entity | shares				0
2023 Notes | Convertible subordinated notes | Stock prices above $38.00 per share | Maximum
Debt
Net shares settlement payable to the entity | shares				2,779,659
2023 Notes | Old Rate [Member] | Convertible subordinated notes
Debt
Effective interest rate		2.36%
2023 Notes | New Rate [Member] | Convertible subordinated notes
Debt
Effective interest rate		2.37%
Innoviva's Common Stock | 2023 Notes | Convertible subordinated notes
Debt
Notes converted into common stock, Amount	$ 3,000
Common stock | 2023 Notes | Convertible subordinated notes
Debt
Conversion rate for shares of common stock per $1,000 principal			50.5818	35.9903
Conversion price (dollars per share) | $ / shares			$ 19.77	$ 27.79