Supplemental Disclosures (Supplemental Operating and Financing Cash Flow Items) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Operating:
Receipt of contingent consideration for dispositions	$ 1	$ 0
Acquisition/disposition related net charges for adjustments	7	10
Adjustments and payments related to contingent consideration	8	10
Financing:
Contingent consideration for prior year acquisitions	(1)	(4)
Deferred consideration related to prior year acquisitions	(12)	(12)
Payments of deferred and contingent consideration for acquisitions	(13)	(16)
Receipts of contingent consideration for dispositions	$ 2	$ 3

Adjustments and Payments Related to Contingent Consideration

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Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings, Net

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Payments For Previous Acquisition, Contingent Consideration

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Payments For Previous Acquisition, Deferred Consideration

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Payments For Previous Acquisition, Deferred and Contingent Consideration

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Proceeds From Contingent Consideration, Prior Period Dispositions

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Proceeds from Previous Disposition, Contingent Consideration

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