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Acquisitions and Dispositions of Businesses - Schedule of Consideration Transferred and Preliminary Value of Intangible Assets (Details) - USD ($) $ in Millions |  | 12 Months Ended |
--- | --- | --- | ---
Apr. 25, 2024 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Consideration transferred: |  |  |  |
Aggregate consideration transferred |  | $ 9,600 | $ 50 |
Assets acquired: |  |  |  |
Goodwill |  | 15,234 | 8,414 | $ 8,292
Liabilities assumed: |  |  |  |
Funds held on behalf of clients |  | 7,247 | $ 6,901 | $ 6,386
2024 Acquisition |  |  |  |
Consideration transferred: |  |  |  |
Cash |  | 3,714 |  |
Deferred, contingent, and other consideration |  | 33 |  |
Class A ordinary shares issued |  | 5,882 |  |
Aggregate consideration transferred |  | 9,629 |  |
Assets acquired: |  |  |  |
Cash and cash equivalents |  | 311 |  |
Receivables |  | 358 |  |
Fiduciary assets |  | 463 |  |
Goodwill |  | 7,125 |  |
Other intangible assets: |  |  |  |
Operating lease right-of-use assets |  | 142 |  |
Current assets |  | 84 |  |
Non-current assets |  | 90 |  |
Total assets acquired |  | 15,613 |  |
Liabilities assumed: |  |  |  |
Accounts payable and accrued liabilities |  | 316 |  |
Fiduciary liabilities |  | 463 |  |
Current liabilities |  | 250 |  |
Long-term debt |  | 3,422 |  |
Non-current operating lease liabilities |  | 129 |  |
Deferred tax liabilities |  | 1,057 |  |
Non-current liabilities |  | 154 |  |
Total liabilities assumed |  | 5,791 |  |
Less: Fair value of redeemable noncontrolling interests |  | (108) |  |
Less: Fair value of nonredeemable noncontrolling interests |  | (85) |  |
Net assets acquired |  | 9,629 |  |
Funds held on behalf of clients |  | 312 |  |
2024 Acquisition | Customer-related and contract-based |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | 6,212 |  |
2024 Acquisition | Tradenames |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | 801 |  |
2024 Acquisition | Technology and other |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | 27 |  |
NFP Acquisition |  |  |  |
Consideration transferred: |  |  |  |
Cash | $ 3,200 | 3,247 |  |
Deferred, contingent, and other consideration |  | 0 |  |
Class A ordinary shares issued |  | 5,882 |  |
Aggregate consideration transferred | $ 9,100 | 9,129 |  |
Assets acquired: |  |  |  |
Cash and cash equivalents |  | 294 |  |
Receivables |  | 328 |  |
Fiduciary assets |  | 411 |  |
Goodwill |  | 6,867 |  |
Other intangible assets: |  |  |  |
Operating lease right-of-use assets |  | 138 |  |
Current assets |  | 82 |  |
Non-current assets |  | 88 |  |
Total assets acquired |  | 14,983 |  |
Liabilities assumed: |  |  |  |
Accounts payable and accrued liabilities |  | 283 |  |
Fiduciary liabilities |  | 411 |  |
Current liabilities |  | 242 |  |
Long-term debt |  | 3,422 |  |
Non-current operating lease liabilities |  | 125 |  |
Deferred tax liabilities |  | 1,026 |  |
Non-current liabilities |  | 152 |  |
Total liabilities assumed |  | 5,661 |  |
Less: Fair value of redeemable noncontrolling interests |  | (108) |  |
Less: Fair value of nonredeemable noncontrolling interests |  | (85) |  |
Net assets acquired |  | 9,129 |  |
NFP Acquisition | Customer-related and contract-based |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | 5,950 |  |
NFP Acquisition | Tradenames |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | 800 |  |
NFP Acquisition | Technology and other |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | 25 |  |
Other Acquisitions |  |  |  |
Consideration transferred: |  |  |  |
Cash |  | 467 |  |
Deferred, contingent, and other consideration |  | 33 |  |
Class A ordinary shares issued |  | 0 |  |
Aggregate consideration transferred |  | 500 |  |
Assets acquired: |  |  |  |
Cash and cash equivalents |  | 17 |  |
Receivables |  | 30 |  |
Fiduciary assets |  | 52 |  |
Goodwill |  | 258 |  |
Other intangible assets: |  |  |  |
Operating lease right-of-use assets |  | 4 |  |
Current assets |  | 2 |  |
Non-current assets |  | 2 |  |
Total assets acquired |  | 630 |  |
Liabilities assumed: |  |  |  |
Accounts payable and accrued liabilities |  | 33 |  |
Fiduciary liabilities |  | 52 |  |
Current liabilities |  | 8 |  |
Long-term debt |  | 0 |  |
Non-current operating lease liabilities |  | 4 |  |
Deferred tax liabilities |  | 31 |  |
Non-current liabilities |  | 2 |  |
Total liabilities assumed |  | 130 |  |
Less: Fair value of redeemable noncontrolling interests |  | 0 |  |
Less: Fair value of nonredeemable noncontrolling interests |  | 0 |  |
Net assets acquired |  | 500 |  |
Other Acquisitions | Customer-related and contract-based |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | 262 |  |
Other Acquisitions | Tradenames |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | 1 |  |
Other Acquisitions | Technology and other |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | $ 2 |  |

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