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No definition available.

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- Definition

Number of persons employed by the Entity

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No definition available.

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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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- Definition

Percentage of voting equity interest acquired in business combination.

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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- Definition

Amount classified as goodwill attributable to disposal group held for sale or disposed of.

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- Definition

Amount classified as intangible assets, excluding goodwill, attributable to disposal group held for sale or disposed of.

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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

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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- Definition

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

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Acquisitions and Dispositions of Businesses - Narrative (Details) $ in Millions			3 Months Ended		9 Months Ended
	Aug. 30, 2026 USD ($) colleague	Oct. 30, 2025 USD ($)	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Mar. 16, 2026	Jan. 01, 2025
Business Combination [Line Items]
Gain on disposition of business			$ 0		$ 20
Gain from sales of businesses			$ 0	$ 1	20	$ 1
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| NFP Intermediate Holdings A Corp.
Business Combination [Line Items]
Purchase price		$ 2,300
Disposal group, not discontinued operation, gain (loss) on disposal		1,200
Intangible assets, net		760
Goodwill		$ 398
Gain from sales of businesses					20
USI Advantage Corp
Business Combination [Line Items]
Purchase price in cash	$ 17,000
Number of colleagues (more than) \| colleague	10,500
ShoreOne Insurance Managers, Inc.
Business Combination [Line Items]
Purchase price in cash					$ 381
Percentage of capital acquired							100.00%
Griffiths & Armour
Business Combination [Line Items]
Percentage of capital acquired								100.00%