Other (Income)/Deductions - Net (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Royalty-related income		$ (3)	$ (3)	$ (7)	$ (9)
Interest income		(1)	(1)	(4)	(9)
Identifiable intangible asset impairment charges		0	0	0	3
Other asset impairment charges		3	0	3	0
Foreign currency loss	[1]	8	3	20	14
Impairment of an equity investment		0	0	0	4
Other, net		(3)	2	1	1
Other (income)/deductions—net		4	0	16	(15)
Zoetis Initiatives
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net (gain)/loss on sale of assets					(18)
Reconciling Items | Zoetis Initiatives
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net (gain)/loss on sale of assets	[2]	$ 0	$ (1)	$ 3	$ (19)

[1] Primarily driven by costs related to hedging and exposures to certain emerging and developed market currencies.

[2] For the nine months ended September 30, 2020, primarily represents a net gain resulting from a cash payment received pursuant to an agreement related to the 2016 sale of certain U.S. manufacturing sites.