Goodwill and Identifiable Intangible Assets - Summary of Goodwill by Segment (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Goodwill
Beginning Balance	$ 12,654	$ 12,159
Business combinations	1,060	115
Impact of foreign currency fluctuations and other	(413)	380
Ending Balance	13,301	12,654
Technology & Analytics Solutions
Goodwill
Beginning Balance	10,864	10,374
Business combinations	874	86
Impact of foreign currency fluctuations and other	(401)	404
Ending Balance	11,337	10,864
Research & Development Solutions
Goodwill
Beginning Balance	1,646	1,646
Business combinations	160	29
Impact of foreign currency fluctuations and other	(4)	(29)
Ending Balance	1,802	1,646
Contract Sales & Medical Solutions
Goodwill
Beginning Balance	144	139
Business combinations	26	0
Impact of foreign currency fluctuations and other	(8)	5
Ending Balance	$ 162	$ 144

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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