Acquisitions and Dispositions of Businesses - Completed Acquisitions (Details) $ in Millions |
3 Months Ended | |||
---|---|---|---|---|
Sep. 01, 2021
USD ($)
|
Mar. 31, 2022
acquisition
|
Mar. 31, 2021
acquisition
|
Dec. 22, 2021 |
|
Business Acquisition [Line Items] | ||||
Number of business acquired under business combination | acquisition | 1 | 0 | ||
For Welfare S.r.l | ||||
Business Acquisition [Line Items] | ||||
Percentage of capital acquired | 100.00% | |||
Aon India Insurance Brokers Limited | ||||
Business Acquisition [Line Items] | ||||
Percentage of capital acquired | 51.00% | |||
Equity interest in acquiree, percentage | 49.00% | |||
Equity interest in acquiree | $ | $ 15 |