Fair Value Measurements - Summary of Assets and Liabilities Recorded at Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Assets
Available-for-sale debt securities	$ 2,293	$ 2,497
MYR
Liabilities:
Liability for MYR GmbH (“MYR”) contingent consideration	275	317
Other publicly traded equity securities
Assets
Total	5,248	5,743
Fair value, recurring
Assets
Total	7,600	8,320
Liabilities:
Total	538	583
Fair value, recurring \| Galapagos
Assets
Marketable equity securities	736	931
Fair value, recurring \| Arcus
Assets
Marketable equity securities	286	559
Fair value, recurring \| MYR
Liabilities:
Liability for MYR GmbH (“MYR”) contingent consideration	275	317
Fair value, recurring \| U.S. treasury securities
Assets
Available-for-sale debt securities	410	407
Fair value, recurring \| U.S. government agencies securities
Assets
Available-for-sale debt securities	35	4
Fair value, recurring \| Non-U.S. government securities
Assets
Available-for-sale debt securities	34	50
Fair value, recurring \| Certificates of deposit
Assets
Available-for-sale debt securities	54	249
Fair value, recurring \| Corporate debt securities
Assets
Available-for-sale debt securities	1,427	1,363
Fair value, recurring \| Residential mortgage and asset-backed securities
Assets
Available-for-sale debt securities	333	424
Fair value, recurring \| Money market funds
Assets
Marketable equity securities	3,831	3,661
Fair value, recurring \| Other publicly traded equity securities
Assets
Marketable equity securities	175	331
Fair value, recurring \| Deferred compensation plan
Assets
Marketable equity securities	220	261
Liabilities:
Deferred compensation plan	220	261
Fair value, recurring \| Foreign currency derivative contracts
Assets
Foreign currency derivative contracts	60	80
Liabilities:
Foreign currency derivative contracts	42	5
Fair value, recurring \| Fair value \| Deferred compensation plan
Assets
Marketable equity securities	220	261
Fair value, recurring \| Level 1
Assets
Total	5,658	6,150
Liabilities:
Total	220	261
Fair value, recurring \| Level 1 \| Galapagos
Assets
Marketable equity securities	736	931
Fair value, recurring \| Level 1 \| Arcus
Assets
Marketable equity securities	286	559
Fair value, recurring \| Level 1 \| MYR
Liabilities:
Liability for MYR GmbH (“MYR”) contingent consideration	0	0
Fair value, recurring \| Level 1 \| U.S. treasury securities
Assets
Available-for-sale debt securities	410	407
Fair value, recurring \| Level 1 \| U.S. government agencies securities
Assets
Available-for-sale debt securities	0	0
Fair value, recurring \| Level 1 \| Non-U.S. government securities
Assets
Available-for-sale debt securities	0	0
Fair value, recurring \| Level 1 \| Certificates of deposit
Assets
Available-for-sale debt securities	0	0
Fair value, recurring \| Level 1 \| Corporate debt securities
Assets
Available-for-sale debt securities	0	0
Fair value, recurring \| Level 1 \| Residential mortgage and asset-backed securities
Assets
Available-for-sale debt securities	0	0
Fair value, recurring \| Level 1 \| Money market funds
Assets
Marketable equity securities	3,831	3,661
Fair value, recurring \| Level 1 \| Other publicly traded equity securities
Assets
Marketable equity securities	175	331
Fair value, recurring \| Level 1 \| Deferred compensation plan
Assets
Marketable equity securities	220	261
Liabilities:
Deferred compensation plan	220	261
Fair value, recurring \| Level 1 \| Foreign currency derivative contracts
Assets
Foreign currency derivative contracts	0	0
Liabilities:
Foreign currency derivative contracts	0	0
Fair value, recurring \| Level 2
Assets
Total	1,943	2,170
Liabilities:
Total	42	5
Fair value, recurring \| Level 2 \| Galapagos
Assets
Marketable equity securities	0	0
Fair value, recurring \| Level 2 \| Arcus
Assets
Marketable equity securities	0	0
Fair value, recurring \| Level 2 \| MYR
Liabilities:
Liability for MYR GmbH (“MYR”) contingent consideration	0	0
Fair value, recurring \| Level 2 \| U.S. treasury securities
Assets
Available-for-sale debt securities	0	0
Fair value, recurring \| Level 2 \| U.S. government agencies securities
Assets
Available-for-sale debt securities	35	4
Fair value, recurring \| Level 2 \| Non-U.S. government securities
Assets
Available-for-sale debt securities	34	50
Fair value, recurring \| Level 2 \| Certificates of deposit
Assets
Available-for-sale debt securities	54	249
Fair value, recurring \| Level 2 \| Corporate debt securities
Assets
Available-for-sale debt securities	1,427	1,363
Fair value, recurring \| Level 2 \| Residential mortgage and asset-backed securities
Assets
Available-for-sale debt securities	333	424
Fair value, recurring \| Level 2 \| Money market funds
Assets
Marketable equity securities	0	0
Fair value, recurring \| Level 2 \| Other publicly traded equity securities
Assets
Marketable equity securities	0	0
Fair value, recurring \| Level 2 \| Deferred compensation plan
Assets
Marketable equity securities	0	0
Liabilities:
Deferred compensation plan	0	0
Fair value, recurring \| Level 2 \| Foreign currency derivative contracts
Assets
Foreign currency derivative contracts	60	80
Liabilities:
Foreign currency derivative contracts	42	5
Fair value, recurring \| Level 3
Assets
Total	0	0
Liabilities:
Total	275	317
Fair value, recurring \| Level 3 \| Galapagos
Assets
Marketable equity securities	0	0
Fair value, recurring \| Level 3 \| Arcus
Assets
Marketable equity securities	0	0
Fair value, recurring \| Level 3 \| MYR
Liabilities:
Liability for MYR GmbH (“MYR”) contingent consideration	275	317
Fair value, recurring \| Level 3 \| U.S. treasury securities
Assets
Available-for-sale debt securities	0	0
Fair value, recurring \| Level 3 \| U.S. government agencies securities
Assets
Available-for-sale debt securities	0	0
Fair value, recurring \| Level 3 \| Non-U.S. government securities
Assets
Available-for-sale debt securities	0	0
Fair value, recurring \| Level 3 \| Certificates of deposit
Assets
Available-for-sale debt securities	0	0
Fair value, recurring \| Level 3 \| Corporate debt securities
Assets
Available-for-sale debt securities	0	0
Fair value, recurring \| Level 3 \| Residential mortgage and asset-backed securities
Assets
Available-for-sale debt securities	0	0
Fair value, recurring \| Level 3 \| Money market funds
Assets
Marketable equity securities	0	0
Fair value, recurring \| Level 3 \| Other publicly traded equity securities
Assets
Marketable equity securities	0	0
Fair value, recurring \| Level 3 \| Deferred compensation plan
Assets
Marketable equity securities	0	0
Liabilities:
Deferred compensation plan	0	0
Fair value, recurring \| Level 3 \| Foreign currency derivative contracts
Assets
Foreign currency derivative contracts	0	0
Liabilities:
Foreign currency derivative contracts	$ 0	$ 0

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