Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Cash And Certain Liabilities

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- Definition

Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Deferred Tax Liabilities

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No definition available.

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Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Notes Receivable

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- Definition

Deferred Consideration On Divestiture

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Disposal Group, Including Discontinued Operation, Deferred Consideration

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- Definition

Gain On Disposition of Business

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Represents the number of entities disposed of by the reporting entity.

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No definition available.

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- Definition

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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- Definition

Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

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

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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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This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to intangibles acquired in connection with a business combination for which the initial accounting was incomplete.

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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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No definition available.

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- Definition

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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Amount of increase (decrease) from measurement period adjustment of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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- Definition

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

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No definition available.

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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 inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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Acquisitions and Dispositions of Businesses - Narrative (Details) shares in Millions			3 Months Ended		95 Months Ended
	Apr. 25, 2024 USD ($) shares	Mar. 01, 2024 USD ($)	Mar. 31, 2025 USD ($) disposition acquisition	Mar. 31, 2024 USD ($) disposition acquisition	Mar. 31, 2025 USD ($)	Jan. 01, 2025	Dec. 31, 2024 USD ($)	May 01, 2017 USD ($)
Business Acquisition [Line Items]
Number of business acquired under business combination \| acquisition			7	0
Issuance of debt		$ 6,000,000,000
Proceeds from long-term lines of credit	$ 2,000,000,000
Decrease in goodwill			$ 21,000,000
Goodwill			$ 15,697,000,000		$ 15,697,000,000		$ 15,234,000,000
Number of dispositions \| disposition			0	1
Gain on disposition of business			$ 0	$ 0
Deferred consideration on divestiture			20,000,000	$ 82,000,000	104,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| May 1, 2017 Divested Business
Business Acquisition [Line Items]
Purchase price								$ 4,300,000,000
Deferred consideration								$ 500,000,000
Griffiths & Armour
Business Acquisition [Line Items]
Percentage of capital acquired						100.00%
NFP Acquisition
Business Acquisition [Line Items]
Percentage of capital acquired	100.00%
Total consideration	$ 9,100,000,000		9,129,000,000
Cash	$ 3,200,000,000		3,247,000,000
Number of shares issued for acquisition (up to) \| shares	19
Equity interest issued or issuable, value	$ 5,900,000,000
Adjustments for cash and certain assumed liabilities	$ 3,900,000,000
Increase of intangible assets			125,000,000
Decrease of acquired notes receivable			107,000,000
Decrease of deferred tax liabilities			103,000,000
Decrease in goodwill			106,000,000
Goodwill			$ 6,847,000,000		6,847,000,000
Weighted average useful life			19 years
Risk Capital
Business Acquisition [Line Items]
Number of business acquired under business combination \| acquisition			6
Decrease in goodwill			$ 8,000,000
Goodwill			9,200,000,000		9,200,000,000		8,785,000,000
Risk Capital \| NFP Acquisition
Business Acquisition [Line Items]
Goodwill			$ 2,600,000,000		2,600,000,000
Human Capital
Business Acquisition [Line Items]
Number of business acquired under business combination \| acquisition			1
Decrease in goodwill			$ 13,000,000
Goodwill			6,497,000,000		6,497,000,000		$ 6,449,000,000
Human Capital \| NFP Acquisition
Business Acquisition [Line Items]
Goodwill			$ 4,200,000,000		$ 4,200,000,000