CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (UNAUDITED) - USD ($) $ in Millions		Total	Common Stock	Treasury Stock		Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Equity Attributable to Noncontrolling Interests	Share Repurchase Program Treasury Stock
Beginning balance (in shares) at Dec. 31, 2019	[1]	501,900,000
Beginning balance at Dec. 31, 2019		$ 2,708	$ 5	$ (2,042)		$ 1,044	$ 4,427	$ (726)	$ 0
Treasury stock, beginning balance (in shares) at Dec. 31, 2019	[1]			26,400,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		423					423
Other comprehensive income		(55)						(55)
Treasury stock acquired, shares	[1]			(1,800,000)	[2]					(1,200,000)	[3]
Share-based compensation awards	[3]	21		$ 40		(28)	9
Treasury stock acquired	[2]	(250)		(250)
Employee benefit plan contribution from Pfizer Inc.	[4]	1				1
Dividends declared		$ (95)					(95)
Ending balance (in shares) at Mar. 31, 2020	[1]	501,900,000
Treasury stock, ending balance (in shares) at Mar. 31, 2020	[1]	27,000,000.0
Ending balance at Mar. 31, 2020		$ 2,753	5	(2,252)		1,017	4,764	(781)	0
Beginning balance (in shares) at Dec. 31, 2020		501,891,243
Beginning balance at Dec. 31, 2020		$ 3,773	5	$ (2,230)		1,065	5,659	(730)	4
Treasury stock, beginning balance (in shares) at Dec. 31, 2020		26,573,492		26,600,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		$ 558					559		(1)
Other comprehensive income		97						97
Treasury stock acquired, shares				(1,100,000)						(800,000)
Share-based compensation awards		(37)		$ (1)		(36)	0
Treasury stock acquired		(181)		$ (181)
Employee benefit plan contribution from Pfizer Inc.		1				1
Dividends declared		$ (119)					(119)
Ending balance (in shares) at Mar. 31, 2021		501,891,243
Treasury stock, ending balance (in shares) at Mar. 31, 2021		26,917,838		26,900,000
Ending balance at Mar. 31, 2021		$ 4,092	$ 5	$ (2,412)		$ 1,030	$ 6,099	$ (633)	$ 3

[1] (a)    Shares may not add due to rounding.

[2] (c)    Reflects the acquisition of treasury shares in connection with the share repurchase program. For additional information, see Note 13. Stockholders' Equity.

[3] (b)    Includes the issuance of shares of Zoetis Inc. common stock and the reacquisition of shares of treasury stock associated with exercises of employee share-based awards. Also includes the reacquisition of shares of treasury stock associated with the vesting of employee share-based awards to satisfy tax withholding requirements. For additional information, see Note 12. Share-based Payments and Note 13. Stockholders' Equity.

[4] (d)    Represents contributed capital from Pfizer Inc. associated with service credit continuation for certain Zoetis Inc. employees in Pfizer Inc.'s U.S. qualified defined benefit and U.S. retiree medical plans.