| **Goodwill and Other Intangible Assets - Narrative (Detail) (USD $)In Billions, unless otherwise specified** | 3 Months Ended | 9 Months Ended |
|--------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Finite Lived and Indefinite Lived Intangible Assets [Line Items]**                                         |           |           |   |   |
| Amortization expense for finite-lived intangible assets                                                      | $ 1.1          | $ 1.2          | $ 3.6 | $ 4.0 |
| Indefinite Lived Brands [Member] | Established Products [Member]                                             |           |           |   |   |
| **Finite Lived and Indefinite Lived Intangible Assets [Line Items]**                                         |           |           |   |   |
| Percentage of indefinite-lived intangible asset unamortized costs by segment                                 | 31.00%         |           | 31.00% |   |
| Indefinite Lived Brands [Member] | Consumer Healthcare [Member]                                              |           |           |   |   |
| **Finite Lived and Indefinite Lived Intangible Assets [Line Items]**                                         |           |           |   |   |
| Percentage of indefinite-lived intangible asset unamortized costs by segment                                 | 69.00%         |           | 69.00% |   |
| In-Process Research And Development [Member] | Specialty Care [Member]                                       |           |           |   |   |
| **Finite Lived and Indefinite Lived Intangible Assets [Line Items]**                                         |           |           |   |   |
| Percentage of indefinite-lived intangible asset unamortized costs by segment                                 | 38.00%         |           | 38.00% |   |
| In-Process Research And Development [Member] | Established Products [Member]                                 |           |           |   |   |
| **Finite Lived and Indefinite Lived Intangible Assets [Line Items]**                                         |           |           |   |   |
| Percentage of indefinite-lived intangible asset unamortized costs by segment                                 | 10.00%         |           | 10.00% |   |
| In-Process Research And Development [Member] | Primary Care [Member]                                         |           |           |   |   |
| **Finite Lived and Indefinite Lived Intangible Assets [Line Items]**                                         |           |           |   |   |
| Percentage of indefinite-lived intangible asset unamortized costs by segment                                 | 9.00%          |           | 9.00% |   |
| In-Process Research And Development [Member] | Worldwide Research and Development [Member]                   |           |           |   |   |
| **Finite Lived and Indefinite Lived Intangible Assets [Line Items]**                                         |           |           |   |   |
| Percentage of indefinite-lived intangible asset unamortized costs by segment                                 | 43.00%         |           | 43.00% |   |
| Developed Technology Rights [Member] | Specialty Care [Member]                                               |           |           |   |   |
| **Finite Lived and Indefinite Lived Intangible Assets [Line Items]**                                         |           |           |   |   |
| Percentage of finite-lived intangible asset amortized cost by segment                                        | 68.00%         |           | 68.00% |   |
| Developed Technology Rights [Member] | Established Products [Member]                                         |           |           |   |   |
| **Finite Lived and Indefinite Lived Intangible Assets [Line Items]**                                         |           |           |   |   |
| Percentage of finite-lived intangible asset amortized cost by segment                                        | 19.00%         |           | 19.00% |   |
| Developed Technology Rights [Member] | Primary Care [Member]                                                 |           |           |   |   |
| **Finite Lived and Indefinite Lived Intangible Assets [Line Items]**                                         |           |           |   |   |
| Percentage of finite-lived intangible asset amortized cost by segment                                        | 12.00%         |           | 12.00% |   |
| Developed Technology Rights [Member] | Oncology [Member]                                                     |           |           |   |   |
| **Finite Lived and Indefinite Lived Intangible Assets [Line Items]**                                         |           |           |   |   |
| Percentage of finite-lived intangible asset amortized cost by segment                                        | 1.00%          |           | 1.00% |   |
| Finite Lived Brands [Member] | Established Products [Member]                                                 |           |           |   |   |
| **Finite Lived and Indefinite Lived Intangible Assets [Line Items]**                                         |           |           |   |   |
| Percentage of finite-lived intangible asset amortized cost by segment                                        | 27.00%         |           | 27.00% |   |
| Finite Lived Brands [Member] | Consumer Healthcare [Member]                                                  |           |           |   |   |
| **Finite Lived and Indefinite Lived Intangible Assets [Line Items]**                                         |           |           |   |   |
| Percentage of finite-lived intangible asset amortized cost by segment                                        | 73.00%         |           | 73.00% |   |

| X                                                                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The percentage of amortized cost of finite-lived intangible assets by segment.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The percentage of unamortized cost of indefinite-lived intangible assets by segment.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275
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