Business Acquisitions (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Goodwill, after measurement period adjustments	$ 24,383	$ 24,228	$ 21,691
Government Business Segment [Member]
Business Acquisition [Line Items]
Goodwill, after measurement period adjustments	10,477	10,349	8,331
Other [Member]
Business Acquisition [Line Items]
Goodwill, after measurement period adjustments	2,236	2,227	$ 1,719
Series of Individually Immaterial Business Acquisitions [Member]
Business Acquisition [Line Items]
Total cash considerations	752
Finite-lived Intangible Assets Acquired	89
Indefinite-lived Intangible Assets Acquired	250
Goodwill, Acquired During Period	145
Series of Individually Immaterial Business Acquisitions [Member] | Acquisition Year, Prior Year
Business Acquisition [Line Items]
Total cash considerations		4,021
Finite-lived Intangible Assets Acquired		1,577
Indefinite-lived Intangible Assets Acquired		$ 20
Goodwill, purchase accounting adjustments	10
Goodwill, after measurement period adjustments	2,531
Series of Individually Immaterial Business Acquisitions [Member] | Government Business Segment [Member] | Acquisition Year, Prior Year
Business Acquisition [Line Items]
Intangible Assets, Net (Including Goodwill)	3,333
Series of Individually Immaterial Business Acquisitions [Member] | Other [Member] | Acquisition Year, Prior Year
Business Acquisition [Line Items]
Intangible Assets, Net (Including Goodwill)	$ 795