|**Basis of Presentation and Significant Accounting Policies (Policies)**            | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
|----------------------------------------------------------------------------------- | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|
|**Organization, Consolidation and Presentation of Financial Statements [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|Basis of Presentation                                                               | Basis of PresentationWe prepared these condensed consolidated financial statements in conformity with U.S. GAAP, consistent in all material respects with those applied in our 2021 Form 10-K. As permitted under the SEC requirements for interim reporting, certain footnotes or other financial information have been condensed or omitted.These financial statements include all normal and recurring adjustments that are considered necessary for the fair statement of results for the interim periods presented. The information included in this Form 10-Q should be read in conjunction with the consolidated financial statements and accompanying notes included in our 2021 Form 10-K.Revenues, expenses, assets and liabilities can vary during each quarter of the year. Therefore, the results and trends in these interim financial statements may not be representative of those for the full year.Pfizer’s fiscal quarter-end for subsidiaries operating outside the U.S. is as of and for the three and six months ended May 29, 2022 and May 30, 2021, and for U.S. subsidiaries is as of and for the three and six months ended July 3, 2022 and July 4, 2021.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, our global contract development and manufacturing organization and a leading supplier of specialty active pharmaceutical ingredients. Biopharma is the only reportable segment. SeeNote 17Ain our 2021 Form 10-K andNote 13below.Business development activities completed in 2021 and 2022 impacted financial results in the periods presented. Discontinued operations in the periods presented relate to the previously divested Meridian subsidiary and post-closing adjustments for other previously divested businesses. SeeNotes 1Aand2Bin our 2021 Form 10-K, andNote 2Bbelow.We have made certain reclassification adjustments to conform prior-period amounts to the current presentation for discontinued operations, acquired IPR&D expenses and segment reporting.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|New Accounting Standard Adopted                                                     | New Accounting Standard Adopted in 2022On January 1, 2022, we early adopted a new accounting standard for contract assets and contract liabilities acquired in a business combination. Under the new standard, acquired contract assets and contract liabilities are required to be recognized and measured by the acquirer on the acquisition date in accordance with Accounting Standards Codification 606. This new guidance generally results in the acquirer recognizing contract assets and contract liabilities at the same amounts that were recorded by the acquiree. Previously, these amounts were recognized by the acquirer at fair value as of the acquisition date. We adopted this new standard on a prospective basis and there was no impact to our consolidated financial statements.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
|Revenues and Trade Accounts Receivable                                              | Revenues and Trade Accounts ReceivableRevenue Recognition––We record revenues from product sales when there is a transfer of control of the product from us to the customer. We typically determine transfer of control based on when the product is shipped or delivered and title passes to the customer. For certain contracts, the finished product may temporarily be stored at our or our third-party subcontractors’ locations under a bill-and-hold arrangement. Revenue is recognized on bill-and-hold arrangements at the point in time when the customer obtains control of the product and all of the following criteria have been met: the arrangement is substantive; the product is identified separately as belonging to the customer; the product is ready for physical transfer to the customer; and we do not have the ability to use the product or direct it to another customer. In determining when the customer obtains control of the product, we consider certain indicators, including whether we have a present right to payment from the customer, whether title and/or significant risks and rewards of ownership have transferred to the customer and whether customer acceptance has been received.Customers––Our prescription pharmaceutical products, with the exception of Paxlovid, are sold principally to wholesalers, but we also sell directly to retailers, hospitals, clinics, government agencies and pharmacies. We principally sell Paxlovid to government agencies. In the U.S., we primarily sell our vaccine products directly to the federal government, CDC, wholesalers, individual provider offices, retail pharmacies and integrated delivery networks. Outside the U.S., we primarily sell our vaccines to government and non-government institutions.Deductions from Revenues––Our accruals for Medicare, Medicaid and related state program and performance-based contract rebates, chargebacks, sales allowances and sales returns and cash discounts are as follows:(MILLIONS)July 3,2022December 31, 2021Reserve againstTrade accounts receivable, less allowance for doubtful accounts$1,057$1,077Other current liabilities:Accrued rebates3,8753,811Other accruals458528Other noncurrent liabilities386433Total accrued rebates and other sales-related accruals$5,776$5,850Trade Accounts Receivable––Trade accounts receivable are stated at their net realizable value. The allowance for credit losses reflects our best estimate of expected credit losses of the receivables portfolio determined on the basis of historical experience, current information, and forecasts of future economic conditions. In developing the estimate for expected credit losses, trade accounts receivables are segmented into pools of assets depending on market (U.S. versus international), delinquency status, and customer type (high risk versus low risk and government versus non-government), and fixed reserve percentages are established for each pool of trade accounts receivables.In determining the reserve percentages for each pool of trade accounts receivables, we considered our historical experience with certain customers and customer types, regulatory and legal environments, country and political risk, and other relevant current and future forecasted macroeconomic factors. These credit risk indicators are monitored on a quarterly basis to determine whether there have been any changes in the economic environment that would indicate the established reserve percentages should be adjusted, and are considered on a regional basis to reflect more geographic-specific metrics. Additionally, write-offs and recoveries of customer receivables are tracked against collections on a quarterly basis to determine whether the reserve percentages remain appropriate. When management becomes aware of certain customer-specific factors that impact credit risk, specific allowances for these known troubled accounts are recorded. Trade accounts receivable are written off after all reasonable means to collect the full amount (including litigation, where appropriate) have been exhausted.
|                                                                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|(MILLIONS)                                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|Reserve againstTrade accounts receivable, less allowance for doubtful accounts      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|Other current liabilities:                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|Accrued rebates                                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|Other accruals                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|Other noncurrent liabilities                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|Total accrued rebates and other sales-related accruals                              |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|Acquired In-Process Research and Development Expenses                               | Acquired In-Process Research and Development ExpensesIn the first quarter of 2022, we began reporting acquired IPR&D expense as a separate line item in our consolidated statements of income.Acquired in-process research and development expensesincludes costs incurred in connection with (a) all upfront and milestone payments on collaboration and in-license agreements, including premiums on equity securities and (b) asset acquisitions of acquired IPR&D. These costs were previously recorded inResearch and development expenses. Prior periods have been revised to conform to the current period presentation. When we acquire net assets that do not constitute a business, as defined in U.S. GAAP, no goodwill is recognized and acquired IPR&D is expensed. The fair value of IPR&D acquired in connection with a business combination is recorded on the balance sheet asIdentifiable intangible assets.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       

X- DefinitionDisclosure of accounting policy for basis of accounting, or basis of presentation, used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).
+ ReferencesNo definition available.
+ Details**Name:**
us-gaap_BasisOfAccountingPolicyPolicyTextBlock**Namespace Prefix:**
us-gaap_**Data Type:**
dtr-types:textBlockItemType**Balance Type:**
na**Period Type:**
duration X- DefinitionDisclosure of accounting policy for costs assigned to identifiable tangible and intangible assets of an acquired entity to be used in the research and development activities of the combined enterprise. An entity also may disclose the appraisal method or significant assumptions used to value acquired research and development assets.
+ ReferencesReference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 730 -SubTopic 20 -Section 50 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=6420387&loc=d3e23199-108380
+ Details**Name:**
us-gaap_InProcessResearchAndDevelopmentPolicy**Namespace Prefix:**
us-gaap_**Data Type:**
dtr-types:textBlockItemType**Balance Type:**
na**Period Type:**
duration X- DefinitionDisclosure of accounting policy pertaining to new accounting pronouncements that may impact the entity's financial reporting. Includes, but is not limited to, quantification of the expected or actual impact.
+ ReferencesNo definition available.
+ Details**Name:**
us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock**Namespace Prefix:**
us-gaap_**Data Type:**
dtr-types:textBlockItemType**Balance Type:**
na**Period Type:**
duration X- ReferencesNo definition available.
+ Details**Name:**
us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract**Namespace Prefix:**
us-gaap_**Data Type:**
xbrli:stringItemType**Balance Type:**
na**Period Type:**
duration X- DefinitionDisclosure of accounting policy for revenue from contract with customer.
+ ReferencesReference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130561-203045Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 20 -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130566-203045Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 18 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130563-203045Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -URI https://asc.fasb.org/topic&trid=49130388Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 20 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130566-203045Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 18 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130563-203045Reference 7: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=126899994&loc=d3e18823-107790Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 20 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130566-203045Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 19 -URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130564-203045Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 20 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130566-203045
+ Details**Name:**
us-gaap_RevenueFromContractWithCustomerPolicyTextBlock**Namespace Prefix:**
us-gaap_**Data Type:**
dtr-types:textBlockItemType**Balance Type:**
na**Period Type:**
duration