FAIR VALUE MEASUREMENTS - Estimated Fair Value and Carrying Value of Unsecured Notes and Liability of Future Royalty (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Level 2 \| Fair value
Fair Value, Assets and Liabilities
Fair value	$ 22,567	$ 21,872
Level 2 \| Carrying value
Fair Value, Assets and Liabilities
Carrying value	23,834	24,088
Level 3 \| Fair value \| Immunomedics, Inc. \| Fair Value, Nonrecurring
Fair Value, Assets and Liabilities
Future royalties	1,230	1,090
Level 3 \| Carrying value \| Immunomedics, Inc. \| Fair Value, Nonrecurring
Fair Value, Assets and Liabilities
Future royalties	$ 1,153	$ 1,141

Carrying value as of the balance sheet date of obligations incurred through that date and payable for royalties.

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