Revenue - Revenue by Product (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Revenue from External Customer [Line Items]
Revenue	$ 2,052	$ 1,948	$ 4,038	$ 3,819
Contract manufacturing & human health
Revenue from External Customer [Line Items]
Revenue	18	20	36	36
Vaccines
Revenue from External Customer [Line Items]
Revenue	446	417	851	830
Parasiticides
Revenue from External Customer [Line Items]
Revenue	536	460	995	850
Anti-infectives
Revenue from External Customer [Line Items]
Revenue	233	259	518	580
Dermatology
Revenue from External Customer [Line Items]
Revenue	319	285	630	533
Other pharmaceuticals
Revenue from External Customer [Line Items]
Revenue	265	248	519	474
Medicated feed additives
Revenue from External Customer [Line Items]
Revenue	85	103	183	215
Animal health diagnostics
Revenue from External Customer [Line Items]
Revenue	87	99	185	188
Other non-pharmaceuticals
Revenue from External Customer [Line Items]
Revenue	63	57	121	113
Total products and services
Revenue from External Customer [Line Items]
Revenue	$ 2,034	$ 1,928	$ 4,002	$ 3,783