Revenue - Revenue by Major Species (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue from External Customer [Line Items]
Revenues		$ 7,776	$ 6,675	$ 6,260
Operating Segments | United States Segment
Revenue from External Customer [Line Items]
Revenues		4,042	3,557	3,203
Operating Segments | International Segment
Revenue from External Customer [Line Items]
Revenues	[1]	3,652	3,035	2,972
Livestock
Revenue from External Customer [Line Items]
Revenues		3,005	2,940	3,030
Livestock | United States Segment
Revenue from External Customer [Line Items]
Revenues		1,052	1,166	1,219
Livestock | International Segment
Revenue from External Customer [Line Items]
Revenues		1,953	1,774	1,811
Companion Animal
Revenue from External Customer [Line Items]
Revenues		4,689	3,652	3,145
Companion Animal | United States Segment
Revenue from External Customer [Line Items]
Revenues		2,990	2,391	1,984
Companion Animal | International Segment
Revenue from External Customer [Line Items]
Revenues		1,699	1,261	1,161
Contract Manufacturing and Human Health Diagnostics [Member]
Revenue from External Customer [Line Items]
Revenues		$ 82	$ 83	$ 85

[1] Revenue denominated in euros was $814 million in 2021, $718 million in 2020 and $742 million in 2019.