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v3.22.1

Acquisitions and Dispositions (Narrative) (Details) $ in Millions |  | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Apr. 01, 2022 USD ($) | Mar. 31, 2022 USD ($) acquisition | Mar. 31, 2021 USD ($) disposition acquisition | Dec. 31, 2021 acquisition | Nov. 30, 2021
Business Acquisition [Line Items] |  |  |  |  |
Number of acquisitions made (in acquisitions) | acquisition |  |  | 0 |  |
Total consideration |  | $ 28 |  |  |
Cash paid |  | 24 |  |  |
Estimated fair value of deferred/contingent consideration |  | 4 | $ 0 |  |
Deferred purchase consideration from prior years' acquisitions |  | 12 | 27 |  |
Deconsolidation of Russian businesses |  | (39) | $ 0 |  |
Number of dispositions | disposition |  |  | 0 |  |
Certain Businesses Primarily in Brazil |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Disposal group, consideration |  | 4 |  |  |
U.S. Affinity Business | Subsequent Event |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Disposal group, consideration | $ 145 |  |  |  |
Gain on disposal | $ 110 |  |  |  |
Marsh India Insurance Brokers Limited |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Percentage of ownership in equity investment |  |  |  | 92.00% | 49.00%
Prior Fiscal Periods Acquisitions |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Estimated fair value of deferred/contingent consideration |  | 4 |  |  |
Current Fiscal Period Acquisitions |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Total consideration |  | 28 |  |  |
Cash paid |  | 24 |  |  |
Estimated fair value of deferred/contingent consideration |  | $ 4 |  |  |
Risk and Insurance Services Segment |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Number of acquisitions made (in acquisitions) | acquisition |  | 1 |  | 8 |
Consulting Segment |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Number of acquisitions made (in acquisitions) | acquisition |  | 2 |  | 1 |
Minimum |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Revenue target period (in years) |  | 2 years |  |  |
Maximum |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Revenue target period (in years) |  | 4 years |  |  |

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