Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Numerator
Net income	$ 423	$ 312
Net income	$ 423	$ 312
Denominator
Weighted-average common shares outstanding	475.6	479.6
Common stock equivalents: stock options, RSUs, PSUs and DSUs	3.4	3.5
Weighted-average common and potential dilutive shares outstanding	479.0	483.1
Earnings per share attributable to Zoetis stockholders—basic (in dollars per share)	$ 0.89	$ 0.65
Earnings per share attributable to Zoetis stockholders—diluted (in dollars per share)	$ 0.88	$ 0.65