Segment, Geographic and Other Revenue Information - Revenues By Geographic Area (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	[1]	$ 81,288	$ 41,651	$ 40,905
US [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues		29,746	21,455	20,326
Developed Europe [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues		18,336	7,788	7,729
Developed Rest Of World [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues		12,506	4,036	4,022
Emerging Markets [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues		$ 20,701	$ 8,372	$ 8,828

[1] On December 31, 2021, we completed the sale of our Meridian subsidiary. Prior to its sale, Meridian was managed as part of the Hospital therapeutic area. On November 16, 2020, we completed the spin-off and the combination of our Upjohn Business with Mylan to form Viatris. On December 21, 2020, Pfizer and Viatris completed the termination of the Mylan-Japan collaboration. Beginning in the fourth quarter of 2021, the financial results of Meridian are reflected as discontinued operations for all periods presented. Beginning in the fourth quarter of 2020, the financial results of the Upjohn Business and Mylan-Japan collaboration were reflected as discontinued operations for all periods presented. Prior-period financial information has been restated, as appropriate. See Note 1A.