Product, Geographic and Other Revenue Information - Revenues By Products (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue from External Customer [Line Items]
Revenues	[1]	$ 41,908	$ 41,172	$ 40,825
Alliance Biopharmaceuticals [Member]
Revenue from External Customer [Line Items]
Revenues		5,418	4,648	3,838
Total Biosimilars [Member]
Revenue from External Customer [Line Items]
Revenues	[2]	1,527	911	769
Total Sterile Injectable Pharmaceuticals [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[3]	5,315	5,013	5,173
Internal Medicine [Member]
Revenue from External Customer [Line Items]
Revenues	[1]	9,003	8,790	8,548
Internal Medicine [Member] | Eliquis [Member]
Revenue from External Customer [Line Items]
Revenues	[1]	4,949	4,220	3,434
Internal Medicine [Member] | Chantix Champix [Member]
Revenue from External Customer [Line Items]
Revenues	[1]	919	1,107	1,085
Internal Medicine [Member] | Premarin Family [Member]
Revenue from External Customer [Line Items]
Revenues	[1]	680	734	832
Internal Medicine [Member] | BMP2 [Member]
Revenue from External Customer [Line Items]
Revenues	[1]	274	287	279
Internal Medicine [Member] | Toviaz [Member]
Revenue from External Customer [Line Items]
Revenues	[1]	252	250	271
Internal Medicine [Member] | All Other Internal Medicine [Member]
Revenue from External Customer [Line Items]
Revenues	[1]	1,930	2,192	2,648
Oncology [Member]
Revenue from External Customer [Line Items]
Revenues		10,867	9,014	7,471
Oncology [Member] | Ibrance [Member]
Revenue from External Customer [Line Items]
Revenues		5,392	4,961	4,118
Oncology [Member] | Xtandi Alliance Revenues [Member]
Revenue from External Customer [Line Items]
Revenues		1,024	838	699
Oncology [Member] | Sutent [Member]
Revenue from External Customer [Line Items]
Revenues		819	936	1,049
Oncology [Member] | Inlyta [Member]
Revenue from External Customer [Line Items]
Revenues		787	477	298
Oncology [Member] | Xalkori [Member]
Revenue from External Customer [Line Items]
Revenues		544	530	524
Oncology [Member] | Bosulif [Member]
Revenue from External Customer [Line Items]
Revenues		450	365	296
Oncology [Member] | Retacrit [Member]
Revenue from External Customer [Line Items]
Revenues	[2]	386	225	82
Oncology [Member] | Lorbrena [Member]
Revenue from External Customer [Line Items]
Revenues		204	115	11
Oncology [Member] | Ruxience [Member]
Revenue from External Customer [Line Items]
Revenues	[2]	170	(1)	0
Oncology [Member] | Braftovi [Member]
Revenue from External Customer [Line Items]
Revenues		160	48	0
Oncology [Member] | Zirabev [Member]
Revenue from External Customer [Line Items]
Revenues	[2]	143	1	0
Oncology [Member] | Mektovi [Member]
Revenue from External Customer [Line Items]
Revenues		142	49	0
Oncology [Member] | Other Oncology Products [Member]
Revenue from External Customer [Line Items]
Revenues		645	470	395
Hospital [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4]	7,961	7,772	7,955
Hospital [Member] | Sulperazon [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4]	618	684	613
Hospital [Member] | Medrol [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4]	402	469	493
Hospital [Member] | Epi Pen [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4]	297	303	303
Hospital [Member] | Zithromax Zmax [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4]	276	336	326
Hospital [Member] | Vfend [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4]	270	346	392
Hospital [Member] | Panzyga [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4]	269	183	39
Hospital [Member] | Precedex [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4]	260	155	213
Hospital [Member] | Fragmin [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4]	252	253	293
Hospital [Member] | Zyvox [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4]	222	251	236
Hospital [Member] | Zavicefta [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4]	212	108	46
Hospital [Member] | Pfizer CentreOne [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4],[5]	926	810	755
Hospital [Member] | Other Anti-infectives [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4]	1,455	1,592	1,661
Hospital [Member] | Other Hospital Products [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[4]	2,502	2,281	2,584
Vaccines [Member]
Revenue from External Customer [Line Items]
Revenues		6,575	6,504	6,332
Vaccines [Member] | Prevenar 13/Prevnar 13 [Member]
Revenue from External Customer [Line Items]
Revenues		5,850	5,847	5,802
Vaccines [Member] | Nimenrix [Member]
Revenue from External Customer [Line Items]
Revenues		221	230	140
Vaccines [Member] | FSME/IMMUN-TicoVac [Member]
Revenue from External Customer [Line Items]
Revenues		196	220	184
Vaccines [Member] | BNT162b2 [Member]
Revenue from External Customer [Line Items]
Revenues		154	0	0
Vaccines [Member] | Other Vaccines Products [Member]
Revenue from External Customer [Line Items]
Revenues		154	207	206
Inflammation and Immunology [Member]
Revenue from External Customer [Line Items]
Revenues		4,567	4,733	4,720
Inflammation and Immunology [Member] | Xeljanz [Member]
Revenue from External Customer [Line Items]
Revenues		2,437	2,242	1,774
Inflammation and Immunology [Member] | Enbrel [Member]
Revenue from External Customer [Line Items]
Revenues		1,350	1,699	2,112
Inflammation and Immunology [Member] | Inflectra/Remsima [Member]
Revenue from External Customer [Line Items]
Revenues	[2]	659	625	642
Inflammation and Immunology [Member] | All Other Inflammation and Immunology Products [Member]
Revenue from External Customer [Line Items]
Revenues		121	167	192
Rare Disease [Member]
Revenue from External Customer [Line Items]
Revenues		2,936	2,278	2,211
Rare Disease [Member] | Vyndaqel/Vyndamax [Member]
Revenue from External Customer [Line Items]
Revenues		1,288	473	148
Rare Disease [Member] | BeneFIX [Member]
Revenue from External Customer [Line Items]
Revenues		454	488	554
Rare Disease [Member] | Genotropin [Member]
Revenue from External Customer [Line Items]
Revenues		427	498	558
Rare Disease [Member] | ReFacto AF Xyntha [Member]
Revenue from External Customer [Line Items]
Revenues		370	426	514
Rare Disease [Member] | Somavert [Member]
Revenue from External Customer [Line Items]
Revenues		277	264	267
Rare Disease [Member] | All Other Rare Disease Products [Member]
Revenue from External Customer [Line Items]
Revenues		120	129	170
Consumer Healthcare Reporting Unit [Member]
Revenue from External Customer [Line Items]
Revenues	[6]	$ 0	$ 2,082	$ 3,587

[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.

[2] Biosimilars are highly similar versions of approved and authorized biological medicines and primarily include revenues from Inflectra/Remsima, Retacrit, Ruxience and Zirabev.

[3] Total Sterile Injectable Pharmaceuticals represents the total of all branded and generic injectable products in the Hospital therapeutic area, including anti-infective sterile injectable pharmaceuticals.

[4] Hospital is a therapeutic area that commercializes our global portfolio of sterile injectable and anti-infective medicines. Hospital also includes Pfizer CentreOne(d). All other Hospital primarily includes revenues from legacy Sterile Injectable Pharmaceuticals (SIP) products (that are not anti-infective products) and, to a much lesser extent, solid oral dose products (that are not anti-infective products). SIP anti-infective products that are not individually listed above are recorded in “All other Anti-infectives”.

[5] Pfizer CentreOne includes revenues from our contract manufacturing and active pharmaceutical ingredient sales operation, including sterile injectables contract manufacturing, and revenues related to our manufacturing and supply agreements.

[6] On July 31, 2019, our Consumer Healthcare business, an OTC medicines business, was combined with GSK’s consumer healthcare business to form a new consumer healthcare JV. See Note 2C.