Business Combination, Contingent Consideration Arrangements, Revenue Target Period

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- Definition

Business Combination, Contingent and Deferred Consideration

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- Definition

Business Combination, Fair Value of Previously-held Equity Method Investment

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- Definition

Payments For Previous Acquisition, Deferred and Contingent Consideration

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- Definition

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

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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- Definition

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

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- Definition

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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- Definition

In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

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

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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No definition available.

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Acquisitions and Dispositions (Narrative) (Details) shares in Millions, $ in Millions, £ in Billions		1 Months Ended	4 Months Ended	9 Months Ended	12 Months Ended
	Sep. 20, 2018 GBP (£)	Dec. 31, 2021 USD ($)	May 31, 2020 shares	Dec. 31, 2019 USD ($)	Dec. 31, 2021 USD ($) acquisition	Dec. 31, 2020 USD ($) acquisition shares	Dec. 31, 2019 USD ($)	Nov. 30, 2021
Business Acquisition [Line Items]
Total purchase consideration					$ 1,400	$ 877
Cash paid					888	694
Estimated contingent consideration					153	183	$ 66
Fair value of previously-held equity method investment					390	0	0
Deferred purchase consideration					117	122	65
Revenue related to acquisitions					114	169	1,200
Net operating income (loss) related to acquisitions					3	11	(40)
Acquisition-related expenses incurred					5	3	125
Cash payments for subsidiaries					$ 5	$ 0	$ 91
Risk and insurance services
Business Acquisition [Line Items]
Number of acquisitions made \| acquisition					8	7
Consulting Segment
Business Acquisition [Line Items]
Number of acquisitions made \| acquisition					1
Certain Businesses Primarily in the U.S., U.K. and Canada
Business Acquisition [Line Items]
Cash proceeds from sale					$ 84	$ 98
Net gain on disposal					$ 50
Marsh India
Business Acquisition [Line Items]
Percentage of interest acquired		92.00%			92.00%	49.00%		49.00%
Step acquisition, remeasurement gain		$ 267
Alexander Forbes
Business Acquisition [Line Items]
Sale of stock, number of shares issued in transaction (in shares) \| shares			240			242
Acquisitions made in prior years
Business Acquisition [Line Items]
Estimated contingent consideration					$ 89	$ 102
Deferred purchase consideration					$ 77	$ 68
JLT Transaction
Business Acquisition [Line Items]
Total purchase consideration \| £	£ 5.2
Cash payments for subsidiaries				$ 79
Minimum
Business Acquisition [Line Items]
Revenue target period					2 years
Maximum
Business Acquisition [Line Items]
Revenue target period					4 years