| **Pension and Postretirement Benefit Plans and Defined Contribution Plans - Healthcare Cost Trend Rate Assumptions (Detail) - Postretirement Plans [Member]**                                                                                                                                              | 12 Months Ended |
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| **Defined Benefit Plan Disclosure [Line Items]**                                                                                                                                                                                                                                                           |                 |   |   |
| Healthcare cost trend rate assumed for next year(a)                                                                                                                                                                                                                                                        | [1]             | 7.40% | 7.00% |
| Rate to which the cost trend rate is assumed to decline                                                                                                                                                                                                                                                    |                 | 4.50% | 4.50% |
| Year that the rate reaches the ultimate trend rate                                                                                                                                                                                                                                                         |                 | 2037 | 2027 |
| Healthcare trend rate, under 65 years of age                                                                                                                                                                                                                                                               |                 | 6.50% |   |
| Healthcare trend rate, 65 years of age and over                                                                                                                                                                                                                                                            |                 | 7.90% |   |
|                                                                                                                                                                                                                                                                                                            |
| [1]In 2015 Pfizer started using separate healthcare cost trend rates for U.S. postretirement plan participants based on their age (6.5% for plan participants up to the age of 65, and 7.9% for plan participants age 65 and over). The rate shown in the table is a blended rate, for ease of comparison. |

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| - Definition
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate, 65 Years of Age and Over
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                  |
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| - Definition
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate, Under 65 Years of Age
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                             |
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| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
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| - Definition
The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Health Care Cost Trend Rate -URI http://asc.fasb.org/extlink&oid=6514820Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
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| - Definition
The ultimate trend rate for health care costs.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
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| - Definition
Year the ultimate health care cost trend rate is expected to be reached, in CCYY format.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920
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