| **Acquisitions, Assets and Liabilities Held for Sale, Licensing Agreements, Research and Development and Collaborative Arrangements, Equity-Method Investments and Cost-Method Investment - Equity and Cost-Method Investments (Details) - USD ($) $ in Millions** | 1 Months Ended | 3 Months Ended | 12 Months Ended |        |           |         |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|-----------------|--------|-----------|---------|
||
| Hisun Pfizer Pharmaceuticals Co. Ltd [Member]                                                                                                                                                                                                                      |           |           |            |   |      |    |   |   |   |   |   |
| **Schedule of Equity Method Investments [Line Items]**                                                                                                                                                                                                             |           |           |            |   |      |    |   |   |   |   |   |
| Equity method investment, registered capital                                                                                                                                                                                                                       |           |           |            |   |      |    |   |   |   |   | $ 250.0 |
| Equity method investments                                                                                                                                                                                                                                          |           | $ 270.0        |            |   |      | $ 270.0 | $ 775.0 |   |   |   | $ 122.5 |
| Equity method investment, ownership percentage                                                                                                                                                                                                                     |           | 49.00%         |            |   |      | 49.00%  | 49.00% |   |   |   |   |
| Equity method investment, other than temporary impairment                                                                                                                                                                                                          |           | $ 241.0        | $ 130.0         | $ 81.0 |      | $ 452.0 | $ 463.0 |   |   |   |   |
| Hisun Pfizer Pharmaceuticals Co. Ltd [Member] | Other Nonoperating Income (Expense) [Member]                                                                                                                                                                       |           |           |            |   |      |    |   |   |   |   |   |
| **Schedule of Equity Method Investments [Line Items]**                                                                                                                                                                                                             |           |           |            |   |      |    |   |   |   |   |   |
| Equity method investment, recognized gain (loss)                                                                                                                                                                                                                   |           |           |            |   | $ (463.0) |    |   |   |   |   |   |
| ViiV Healthcare Limited [Member]                                                                                                                                                                                                                                   |           |           |            |   |      |    |   |   |   |   |   |
| **Schedule of Equity Method Investments [Line Items]**                                                                                                                                                                                                             |           |           |            |   |      |    |   |   |   |   |   |
| Equity method investment, ownership percentage                                                                                                                                                                                                                     |           |           |            |   |      |    |   |   | 11.70% | 12.60% |   |
| ViiV Healthcare Limited [Member] | Other Nonoperating Income (Expense) [Member]                                                                                                                                                                                    |           |           |            |   |      |    |   |   |   |   |   |
| **Schedule of Equity Method Investments [Line Items]**                                                                                                                                                                                                             |           |           |            |   |      |    |   |   |   |   |   |
| Gain (loss) in increase (reduction) of interest in subsidiary or equity method investment                                                                                                                                                                          |           |           |            |   |      |    |   | $ (30.0) |   |   |   |
| Laboratorio Teuto Brasilero [Member]                                                                                                                                                                                                                               |           |           |            |   |      |    |   |   |   |   |   |
| **Schedule of Equity Method Investments [Line Items]**                                                                                                                                                                                                             |           |           |            |   |      |    |   |   |   |   |   |
| Equity method investment, ownership percentage                                                                                                                                                                                                                     |           | 40.00%         |            |   |      | 40.00%  |   |   |   |   |   |
| Equity method investment, other than temporary impairment                                                                                                                                                                                                          |           |           |            |   |      | $ 50.0  |   | 56.0 |   |   |   |
| Laboratorio Teuto Brasilero [Member] | Laboratorio Teuto Brasilero [Member]                                                                                                                                                                                        |           |           |            |   |      |    |   |   |   |   |   |
| **Schedule of Equity Method Investments [Line Items]**                                                                                                                                                                                                             |           |           |            |   |      |    |   |   |   |   |   |
| Noncontrolling interest, ownership percentage by parent                                                                                                                                                                                                            |           | 60.00%         |            |   |      | 60.00%  |   |   |   |   |   |
| Laboratorio Teuto Brasilero [Member] | Other Nonoperating Income (Expense) [Member]                                                                                                                                                                                |           |           |            |   |      |    |   |   |   |   |   |
| **Schedule of Equity Method Investments [Line Items]**                                                                                                                                                                                                             |           |           |            |   |      |    |   |   |   |   |   |
| Equity method investment, recognized gain (loss)                                                                                                                                                                                                                   |           |           |            |   |      |    |   | 55.0 |   |   |   |
| Equity method investment, other than temporary impairment                                                                                                                                                                                                          |           |           |            |   |      | $ 50.0  |   | $ 56.0 |   |   |   |
| AM Pharma BV [Member]                                                                                                                                                                                                                                              |           |           |            |   |      |    |   |   |   |   |   |
| **Schedule of Equity Method Investments [Line Items]**                                                                                                                                                                                                             |           |           |            |   |      |    |   |   |   |   |   |
| Cost method investment, contingent payments, maximum exposure                                                                                                                                                                                                      | $ 512.5        |           |            |   |      |    |   |   |   |   |   |
| Long-term Investments [Member] | AM Pharma BV [Member]                                                                                                                                                                                                             |           |           |            |   |      |    |   |   |   |   |   |
| **Schedule of Equity Method Investments [Line Items]**                                                                                                                                                                                                             |           |           |            |   |      |    |   |   |   |   |   |
| Cost method investment, upfront and milestone payments                                                                                                                                                                                                             | $ 87.5         |           |            |   |      |    |   |   |   |   |   |

| X                                                                                                                                                                                                                                                                                  |
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Cost Method, Contingent Payments, Maximum Exposure
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Equity Method Investment, Recognized Gain (Loss)
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Gain (Loss) On Increase (Reduction) of Interest in Subsidiary or Equity Method Investment
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| - Definition
This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of equity, including noncontrolling interest, reported by an equity method investment of the entity.
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| - Definition
This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.
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| - Definition
The parent entity's interest in net assets of the subsidiary, expressed as a percentage.
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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.
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