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v3.25.1

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 |  |  |

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