v3.20.4
Product, Geographic and Other Revenue Information - Revenues By Geographic Area (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]      
Revenues [1] $ 41,908 $ 41,172 $ 40,825
US [Member]      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Revenues 21,712 20,593 20,119
Developed Europe [Member]      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Revenues 7,788 7,729 7,997
Developed Rest Of World [Member]      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Revenues 4,036 4,022 4,090
Emerging Markets [Member]      
Revenues from External Customers and Long-Lived Assets [Line Items]      
Revenues $ 8,372 $ 8,828 $ 8,618
[1] 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 a pre-existing strategic collaboration between Pfizer and Mylan for generic drugs in Japan (Mylan-Japan) and we transferred the operations that were part of the Mylan-Japan collaboration to Viatris. Beginning in the fourth quarter of 2020, the financial results of the Upjohn Business and the Mylan-Japan collaboration are reported as Income from discontinued operations––net of tax for all periods presented. Prior-period financial information has been restated, as appropriate. Prior to the separation of the Upjohn Business, and beginning in 2020, Upjohn began managing our Meridian subsidiary, the manufacturer of EpiPen and other auto-injector products, and the Mylan-Japan collaboration. As a result, revenues associated with our Meridian subsidiary, except for product revenues for EpiPen sold in Canada, and Mylan-Japan were reported in Upjohn beginning in the first quarter of 2020. Beginning in the fourth quarter of 2020, the results of our Meridian subsidiary are reported in the Hospital therapeutic area for all periods presented in our consolidated financial statements.