Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jul. 02, 2017	Jul. 03, 2016	Jul. 02, 2017	Jul. 03, 2016
Numerator
Net income before allocation to noncontrolling interests	$ 247	$ 224	$ 486	$ 428
Less: net income attributable to noncontrolling interests	0	0	1	0
Net income attributable to Zoetis Inc.	$ 247	$ 224	$ 485	$ 428
Denominator
Weighted-average common shares outstanding	490.8	496.3	491.6	496.9
Common stock equivalents: stock options, RSUs, PSUs and DSUs	3.2	2.5	3.0	2.3
Weighted-average common and potential dilutive shares outstanding	494.0	498.8	494.6	499.2
Earnings per share attributable to Zoetis stockholders—basic (in dollars per share)	$ 0.50	$ 0.45	$ 0.99	$ 0.86
Earnings per share attributable to Zoetis stockholders—diluted (in dollars per share)	$ 0.50	$ 0.45	$ 0.98	$ 0.86
Stock options
Denominator
Antidilutive securities excluded from computation of earnings per share, amount	1.0	2.0	1.0	2.0