Revenue - Revenue by Species (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenue from External Customer [Line Items]
Revenue	$ 2,190	$ 2,000
Contract manufacturing & human health
Revenue from External Customer [Line Items]
Revenue	20	17
Dogs and Cats
Revenue from External Customer [Line Items]
Revenue	1,384	1,153
Horses
Revenue from External Customer [Line Items]
Revenue	66	72
Cattle
Revenue from External Customer [Line Items]
Revenue	391	399
Swine
Revenue from External Customer [Line Items]
Revenue	127	142
Poultry [Member]
Revenue from External Customer [Line Items]
Revenue	139	139
Fish
Revenue from External Customer [Line Items]
Revenue	45	49
Sheep and other
Revenue from External Customer [Line Items]
Revenue	18	29
Livestock
Revenue from External Customer [Line Items]
Revenue	720	758
Companion animal
Revenue from External Customer [Line Items]
Revenue	1,450	1,225
Other pharmaceutical
Revenue from External Customer [Line Items]
Revenue	$ 156	$ 178