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FAIR VALUE MEASUREMENTS - Equity Investment In Galapagos (Details) - Galapagos NV - USD ($) $ in Millions | Sep. 30, 2021 | Dec. 31, 2020
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Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Equity investment | $ 881 | $ 1,648
Prepaid and other current assets |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Equity investment | 0 | 351
Other long-term assets |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |
Equity investment | $ 881 | $ 1,297

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- Details
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