Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

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Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

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No definition available.

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The number of businesses acquired by the entity during the period.

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Acquisitions and Dispositions of Businesses - Completed Acquisitions (Details) $ in Millions		12 Months Ended
	Sep. 01, 2021 USD ($)	Dec. 31, 2022 USD ($) acquisition	Dec. 31, 2021 acquisition	Nov. 01, 2022	May 03, 2022	Dec. 22, 2021	Aug. 31, 2021
Business Acquisition [Line Items]
Number of business acquired under business combination \| acquisition		5	2
Weighted average useful life		9 years
Revenues from acquisitions included in the Company's Consolidated Statement of Income		$ 25
E.R.N. Evaluacion de Riesgos Naturales y Antropogenicos, S.A. de C.V
Business Acquisition [Line Items]
Percentage of capital acquired				100.00%
Karl Köllner Group
Business Acquisition [Line Items]
Percentage of capital acquired					100.00%
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