Segment, Geographic and Other Revenue Information - Revenues By Products (Detail) $ in Millions		3 Months Ended		6 Months Ended
		Jul. 03, 2022 USD ($)	Jul. 04, 2021 USD ($)	Jul. 03, 2022 USD ($) operatingSegment	Jul. 04, 2021 USD ($)
Revenue from External Customer [Line Items]
Revenues	[1]	$ 27,742	$ 18,899	$ 53,402	$ 33,415
Number of segments | operatingSegment				2
Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues	[1],[2]	27,425	18,463	$ 52,748	32,588
Pfizer CentreOne [Member]
Revenue from External Customer [Line Items]
Revenues	[2]	317	437	655	827
BioNTech [Member] | Pfizer CentreOne [Member]
Revenue from External Customer [Line Items]
Revenues		55	87	101	87
Total Alliance revenues [Member]
Revenue from External Customer [Line Items]
Revenues		2,317	1,880	4,631	3,650
Total Biosimilars [Member]
Revenue from External Customer [Line Items]
Revenues	[3]	580	559	1,185	1,089
Total Sterile Injectable Pharmaceuticals [Member]
Revenue from External Customer [Line Items]
Revenues	[4]	1,286	1,381	2,617	2,863
Vaccines [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		10,459	9,234	25,399	14,127
Vaccines [Member] | Comirnaty direct sales and alliance revenues [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		8,848	7,838	22,075	11,300
Vaccines [Member] | Prevnar Family [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues	[5]	1,429	1,241	2,994	2,524
Vaccines [Member] | Nimenrix [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		65	49	142	95
Vaccines [Member] | FSME/IMMUN-TicoVac [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		68	61	110	114
Vaccines [Member] | All other Vaccines [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		49	46	78	94
Hospital [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues	[1]	9,714	1,745	12,905	3,630
Hospital [Member] | Paxlovid [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		8,115	0	9,585	0
Hospital [Member] | Sulperazon [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		210	141	420	334
Hospital [Member] | Zithromax [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		54	43	180	132
Hospital [Member] | IVIg Products [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues	[6]	125	107	232	212
Hospital [Member] | Zavicefta [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		100	104	204	198
Hospital [Member] | Medrol [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		79	112	155	211
Hospital [Member] | Fragmin [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		72	77	142	149
Hospital [Member] | Vfend [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		54	72	119	153
Hospital [Member] | All other Anti-infectives [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		367	474	749	929
Hospital [Member] | All other Hospital [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		537	613	1,120	1,314
Oncology [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		3,088	3,145	6,055	6,007
Oncology [Member] | Ibrance [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		1,320	1,404	2,557	2,657
Oncology [Member] | Xtandi alliance revenues [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		290	303	558	570
Oncology [Member] | Inlyta [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		274	257	508	486
Oncology [Member] | Zirabev [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues	[3]	138	129	286	215
Oncology [Member] | Bosulif [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		156	136	284	259
Oncology [Member] | Xalkori [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		118	120	244	255
Oncology [Member] | Ruxience [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues	[3]	113	120	237	218
Oncology [Member] | Retacrit [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues	[3]	106	103	221	212
Oncology [Member] | Sutent [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		97	194	211	394
Oncology [Member] | Lorbrena [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		77	66	149	126
Oncology [Member] | Bavencio Alliance Revenues [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		58	37	125	68
Oncology [Member] | Aromasin [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		59	51	121	103
Oncology [Member] | Trazimera [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues	[3]	46	41	98	87
Oncology [Member] | Besponsa [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		58	45	109	95
Oncology [Member] | Braftovi [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues	[7]	51	42	98	89
Oncology [Member] | Mektovi [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		44	36	84	71
Oncology [Member] | All other Oncology [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		82	60	163	102
Internal Medicine [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		2,405	2,403	4,846	4,997
Internal Medicine [Member] | Eliquis [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		1,745	1,481	3,537	3,124
Internal Medicine [Member] | Premarin family [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		115	128	217	271
Internal Medicine [Member] | BMP2 [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		75	66	142	115
Internal Medicine [Member] | Toviaz [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		45	62	99	119
Internal Medicine [Member] | Chantix / Champix [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		1	184	4	401
Internal Medicine [Member] | All other Internal Medicine [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		424	482	846	966
Rare Disease [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		909	895	1,872	1,720
Rare Disease [Member] | Vyndaqel/Vyndamax [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		552	501	1,164	953
Rare Disease [Member] | BeneFIX [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		113	112	225	225
Rare Disease [Member] | Genotropin [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		91	109	171	189
Rare Disease [Member] | Somavert [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		64	68	132	133
Rare Disease [Member] | ReFacto AF/Xyntha [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		64	77	129	165
Rare Disease [Member] | All other Rare Disease [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		25	29	50	55
Inflammation and Immunology (I&I) [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		850	1,041	1,671	2,107
Inflammation and Immunology (I&I) [Member] | Xeljanz [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		430	586	802	1,124
Inflammation and Immunology (I&I) [Member] | Enbrel [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		257	286	537	605
Inflammation and Immunology (I&I) [Member] | Inflectra [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues	[3]	137	136	272	313
Inflammation and Immunology (I&I) [Member] | All other I & I [Member] | Biopharma [Member]
Revenue from External Customer [Line Items]
Revenues		$ 25	$ 33	$ 60	$ 65

[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. Beginning in the fourth quarter of 2021, the financial results of Meridian were reflected as discontinued operations. Prior-period financial information has been restated, as appropriate. See Note 1A.

[2] At the beginning of our fiscal fourth quarter of 2021, we reorganized our commercial operations and began to manage our commercial operations through a new global structure consisting of two operating segments, each led by a single manager: Biopharma, our innovative science-based biopharmaceutical business, and PC1. PC1, which previously had been managed within the Hospital therapeutic area, includes revenues from our contract manufacturing, including certain Comirnaty-related manufacturing activities performed on behalf of BioNTech ($55 million and $101 million for the second quarter and the first six months of 2022, respectively, and $87 million for both the second quarter and the first six months of 2021), and revenues from our active pharmaceutical ingredient sales operation, as well as revenues related to our manufacturing and supply agreements with former legacy Pfizer businesses/partnerships, including but not limited to, transitional manufacturing and supply agreements with Viatris following the spin-off of the Upjohn Business. We have revised prior-period information to conform to the current management structure.

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

[4] 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.

[5] Prevnar family include revenues from Prevnar 13/Prevenar 13 (pediatric and adult) and Prevnar 20/Apexxnar (adult).

[6] Immunoglobulin (Ig) portfolio includes the revenues from Panzyga, Octagam and Cutaquig.

[7] Erbitux® is a registered trademark of ImClone LLC.