| **Acquisition and Equity-Method Investment - Array BioPharma (Details) - Array [Member] $ / shares in Units, $ in Billions** | Jul. 30, 2019 USD ($) $ / shares |
|------------------------------------------------------------------------------------------------------------------------------|----------------------------------|
| **Business Acquisition [Line Items]**                                                                                        |                             |
| Business acquisition, per share in cash (in dollars per share) | $ / shares                                                  | $ 48                             |
| Payments for acquisition, cash portion                                                                                       | $ 11.2                           |
| Acquisition of business, net of cash acquired                                                                                | $ 10.9                           |

| X                                                                                                                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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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| - Definition
Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
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| - Definition
The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.
+ References
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| X                                                                                                                                       |
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