Revenue - Revenue by Product (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Revenue from External Customer [Line Items]
Revenue	$ 2,460	$ 2,361	$ 4,680	$ 4,551
Total products and services
Revenue from External Customer [Line Items]
Revenue	2,426	2,343	4,617	4,513
Parasiticides
Revenue from External Customer [Line Items]
Revenue	673	600	1,235	1,104
Vaccines
Revenue from External Customer [Line Items]
Revenue	504	445	951	897
Dermatology
Revenue from External Customer [Line Items]
Revenue	463	418	853	781
Anti-infectives
Revenue from External Customer [Line Items]
Revenue	219	264	468	545
Pain and sedation
Revenue from External Customer [Line Items]
Revenue	217	221	427	415
Other pharmaceutical
Revenue from External Customer [Line Items]
Revenue	172	153	331	309
Animal health diagnostics
Revenue from External Customer [Line Items]
Revenue	110	103	213	185
Other non-pharmaceutical
Revenue from External Customer [Line Items]
Revenue	63	65	129	126
Medicated feed additives
Revenue from External Customer [Line Items]
Revenue	5	74	10	151
Contract manufacturing & human health
Revenue from External Customer [Line Items]
Revenue	$ 34	$ 18	$ 63	$ 38