Revenue - Revenue by Species (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Revenue from External Customer [Line Items]
Revenue	$ 2,002	$ 1,990	$ 6,040	$ 5,809
Contract manufacturing & human health
Revenue from External Customer [Line Items]
Revenue	23	21	59	57
Dogs and Cats
Revenue from External Customer [Line Items]
Revenue	1,213	1,142	3,715	3,319
Horses
Revenue from External Customer [Line Items]
Revenue	58	60	185	188
Cattle
Revenue from External Customer [Line Items]
Revenue	371	403	1,063	1,144
Swine
Revenue from External Customer [Line Items]
Revenue	129	153	427	504
Poultry
Revenue from External Customer [Line Items]
Revenue	116	124	361	389
Fish
Revenue from External Customer [Line Items]
Revenue	60	56	151	132
Sheep and other
Revenue from External Customer [Line Items]
Revenue	32	31	79	76
Livestock
Revenue from External Customer [Line Items]
Revenue	708	767	2,081	2,245
Companion animal
Revenue from External Customer [Line Items]
Revenue	1,271	1,202	3,900	3,507
Other pharmaceuticals
Revenue from External Customer [Line Items]
Revenue	$ 252	$ 243	$ 771	$ 717