Revenue - Revenue by Major Species (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Revenue from External Customer [Line Items]
Revenues		$ 9,256	$ 8,544	$ 8,080
Operating Segments | United States Segment
Revenue from External Customer [Line Items]
Revenues		5,074	4,555	4,313
Operating Segments | International Segment
Revenue from External Customer [Line Items]
Revenues	[1]	4,102	3,911	3,681
Livestock
Revenue from External Customer [Line Items]
Revenues		2,898	2,890	2,791
Livestock | United States Segment
Revenue from External Customer [Line Items]
Revenues		1,020	1,026	972
Livestock | International Segment
Revenue from External Customer [Line Items]
Revenues		1,878	1,864	1,819
Companion Animal
Revenue from External Customer [Line Items]
Revenues		6,278	5,576	5,203
Companion Animal | United States Segment
Revenue from External Customer [Line Items]
Revenues		4,054	3,529	3,341
Companion Animal | International Segment
Revenue from External Customer [Line Items]
Revenues		2,224	2,047	1,862
Contract Manufacturing and Human Health Diagnostics [Member]
Revenue from External Customer [Line Items]
Revenues		$ 80	$ 78	$ 86

[1] Operating expenses primarily consisted of field selling, advertising and promotions, other marketing expenses, and freight and logistics costs. (c) Revenue denominated in euros was $937 million in 2024, $853 million in 2023 and $774 million in 2022.