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Collaborative Arrangements - Schedule of Transactions (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Sales | $ 12,080 | $ 12,057 |
Cost of sales | 3,670 | 3,312 |
Selling, general and administrative | 2,633 | 2,555 |
Research and development | 2,465 | 2,209 |
Payables, current | 26,361 |  | $ 27,327
Other current assets | AstraZeneca | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Receivables from Bayer included in Other current assets | 236 |  | 215
Other current assets | Eisai | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Receivables from Bayer included in Other current assets | 153 |  | 157
Other current assets | Bayer AG | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Receivables from Bayer included in Other current assets | 68 |  | 65
Accounts payable and accrued liabilities | AstraZeneca | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Payables, current | 417 |  | 423
Accounts payable and accrued liabilities | Eisai | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Payables, current | 300 |  | 335
Other Noncurrent Liabilities | Eisai | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Payables to Bayer included in Other Noncurrent Liabilities | 300 |  | 600
Other Noncurrent Liabilities | Bayer AG | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Payables to Bayer included in Other Noncurrent Liabilities | 400 |  | $ 0
Revenue | AstraZeneca | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Alliance revenue - profit sharing | 233 | 145 |
Revenue | AstraZeneca | Collaborative Arrangement | Alliance revenue - Lynparza (1) |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Alliance revenue - profit sharing | 228 | 145 |
Revenue | AstraZeneca | Collaborative Arrangement | Alliance revenue - Koselugo |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Alliance revenue - profit sharing | 5 | 0 |
Revenue | Eisai | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Alliance revenue - profit sharing | 130 | 128 |
Revenue | Bayer AG | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Alliance revenue - profit sharing | 74 | 53 |
Collaborative Arrangement, Sales, Net | 55 | 56 |
Sales | 129 | 109 |
Cost of sales | AstraZeneca | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Cost of sales | 42 | 28 |
Cost of sales | Eisai | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Cost of sales | 47 | 35 |
Cost of sales | Bayer AG | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Cost of sales | 189 | 28 |
Amortization of intangible assets | 153 |  |
Selling, general and administrative | AstraZeneca | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Selling, general and administrative | 40 | 33 |
Selling, general and administrative | Eisai | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Selling, general and administrative | 23 | 11 |
Selling, general and administrative | Bayer AG | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Selling, general and administrative | 32 | 15 |
Research and development | AstraZeneca | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Research and development | 29 | 36 |
Research and development | Eisai | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Research and development | 64 | 64 |
Research and development | Bayer AG | Collaborative Arrangement |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Research and development | $ 7 | $ 25 |

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