Segment Information - Income Statement (Details) - USD ($) $ in Millions		3 Months Ended								12 Months Ended
		Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Oct. 01, 2017	Jul. 02, 2017	Apr. 02, 2017	Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenues		$ 1,564	$ 1,480	$ 1,415	$ 1,366	$ 1,460	$ 1,347	$ 1,269	$ 1,231	$ 5,825		$ 5,307		$ 4,888
Cost of Sales	[1]									1,911		1,775		1,666
Other (income)/deductions										(83)		6		(2)
Earnings		418	$ 418	$ 437	$ 417	430	$ 413	$ 345	$ 337	1,690	[2]	1,525	[2]	1,228	[2]
Depreciation and Amortization	[2],[3]									308		242		240
Acquisition-related costs, earnings										61
Property, plant and equipment, less accumulated depreciation		1,658				1,435				1,658		1,435
United States
Segment Reporting Information [Line Items]
Property, plant and equipment, less accumulated depreciation		1,188				1,047				1,188		1,047
International Segment
Segment Reporting Information [Line Items]
Property, plant and equipment, less accumulated depreciation		$ 470				$ 388				470		388
Other business activities
Segment Reporting Information [Line Items]
Earnings										(337)		(313)		(309)
Depreciation and Amortization	[3]									23		23		25
Corporate
Segment Reporting Information [Line Items]
Depreciation and Amortization	[3]									59
Acquisition-related costs
Segment Reporting Information [Line Items]
Depreciation and Amortization	[3]									0		0		0
United States
Segment Reporting Information [Line Items]
Revenues										2,877		2,620		2,447
Operating Segments
Segment Reporting Information [Line Items]
Earnings										3,214		2,877		2,562
Depreciation and Amortization	[3]									82		73		71
Operating Segments | United States Segment
Segment Reporting Information [Line Items]
Revenues										2,877		2,620		2,447
Cost of Sales										606		565		551
Gross Profit										$ 2,271		$ 2,055		$ 1,896
Gross Margin										78.90%		78.40%		77.50%
Operating Expenses										$ 456		$ 421		$ 388
Other (income)/deductions										0		3		0
Earnings										1,815		1,637		1,508
Depreciation and Amortization	[3]									34		29		27
Operating Segments | International Segment
Segment Reporting Information [Line Items]
Revenues	[4]									2,890		2,643		2,390
Cost of Sales										929
Gross Profit										$ 1,961
Gross Margin										67.90%
Operating Expenses										$ 559
Other (income)/deductions										(3)
Earnings										1,399
Operating Segments | International
Segment Reporting Information [Line Items]
Cost of Sales												889		833
Gross Profit												$ 1,754		$ 1,557
Gross Margin												66.40%		65.10%
Operating Expenses												$ 515		$ 501
Other (income)/deductions												1		(2)
Earnings												1,240		1,054
Depreciation and Amortization	[3]									48		44		44
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Earnings										(666)		(625)		(684)
Depreciation and Amortization	[3]											52		45
Segment Reconciling Items
Segment Reporting Information [Line Items]
Purchase accounting adjustments, earnings										(162)		(88)		(99)
Purchase accounting adjustments, depreciation and amortization	[3]									143		88		84
Acquisition-related costs, earnings										(63)		(10)		(4)
Certain significant items, earnings	[5]									43		(25)		(57)
Certain significant items, depreciation and amortization	[3],[5]									0		0		7
Other unallocated, earnings										(339)		(291)		(181)
Other unallocated, deprecation and amortization	[3]									$ 1		$ 6		$ 8

[1] Exclusive of amortization of intangible assets, except as disclosed in Note 3. Significant Accounting Policies—Amortization of Intangible Assets, Depreciation and Certain Long-Lived Assets.

[2] Defined as income before provision for taxes on income.

[3] Certain production facilities are shared. Depreciation and amortization is allocated to the reportable operating segments based on estimates of where the benefits of the related assets are realized.

[4] Revenue denominated in euros was $745 million in 2018, $660 million in 2017, and $632 million in 2016.

[5] For 2018, certain significant items primarily includes: (i) a net gain of $42 million related to the divestiture of certain agribusiness products within our International segment, (ii) a net gain of $18 million related to the relocation of a manufacturing site in China, (iii) charges related to our operational efficiency initiative and supply network strategy initiative of $9 million; and (iv) employee termination costs in Europe of $7 million. For 2017, certain significant items primarily includes: (i) charges related to our operational efficiency initiative and supply network strategy initiative of $20 million; (ii) Zoetis stand-up costs of $3 million; (iii) employee termination costs in Europe of $4 million, (iv) income related to a commercial settlement in Mexico recorded in 2014 and 2016 of $5 million; and (iv) charges of $3 million associated with changes to our operating model. For 2016, certain significant items primarily includes: (i) Zoetis stand-up costs of $23 million; (ii) charges related to our operational efficiency initiative and supply network strategy initiative of $10 million; (iii) charges related to a commercial settlement in Mexico of $14 million; and (iv) charges of $10 million associated with changes to our operating model.