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Acquisitions and Dispositions of Businesses - Schedule of Consideration Transferred and Preliminary Value of Intangible Assets (Details) - USD ($) $ in Millions |  | 6 Months Ended |  |
--- | --- | --- | --- | ---
Apr. 25, 2024 | Jun. 30, 2024 | Dec. 31, 2023 | Jun. 30, 2023
Assets acquired: |  |  |  |
Goodwill |  | $ 15,281 | $ 8,414 |
Liabilities assumed: |  |  |  |
Funds held on behalf of clients |  | 7,309 |  | $ 7,538
2024 Acquisition |  |  |  |
Consideration transferred: |  |  |  |
Cash |  | 3,356 |  |
Deferred and contingent consideration |  | 7 |  |
Class A ordinary shares issued |  | 5,882 |  |
Aggregate consideration transferred |  | 9,245 |  |
Assets acquired: |  |  |  |
Cash and cash equivalents |  | 296 |  |
Receivables |  | 324 |  |
Fiduciary assets |  | 417 |  |
Goodwill |  | 7,022 |  |
Other intangible assets: |  |  |  |
Operating lease right-of-use assets |  | 145 |  |
Current assets |  | 113 |  |
Non-current assets |  | 170 |  |
Total assets acquired |  | 15,188 |  |
Liabilities assumed: |  |  |  |
Accounts payable and accrued liabilities |  | 291 |  |
Fiduciary liabilities |  | 417 |  |
Current liabilities |  | 227 |  |
Long-term debt |  | 3,422 |  |
Non-current operating lease liabilities |  | 127 |  |
Deferred tax liabilities |  | 1,129 |  |
Non-current liabilities |  | 142 |  |
Total liabilities assumed |  | 5,755 |  |
Less: Fair value of redeemable noncontrolling interests |  | (103) |  |
Less: Fair value of nonredeemable noncontrolling interests |  | (85) |  |
Net assets acquired |  | 9,245 |  |
Funds held on behalf of clients |  | 283 |  |
2024 Acquisition | Customer-related and contract-based |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | 5,875 |  |
2024 Acquisition | Tradenames |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | 800 |  |
2024 Acquisition | Technology and other |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | 26 |  |
NFP Acquisition |  |  |  |
Consideration transferred: |  |  |  |
Cash | $ 3,200 | 3,247 |  |
Deferred and contingent consideration |  | 0 |  |
Class A ordinary shares issued |  | 5,882 |  |
Aggregate consideration transferred | $ 9,100 | 9,129 |  |
Assets acquired: |  |  |  |
Cash and cash equivalents |  | 293 |  |
Receivables |  | 321 |  |
Fiduciary assets |  | 411 |  |
Goodwill |  | 6,953 |  |
Other intangible assets: |  |  |  |
Operating lease right-of-use assets |  | 143 |  |
Current assets |  | 110 |  |
Non-current assets |  | 169 |  |
Total assets acquired |  | 15,050 |  |
Liabilities assumed: |  |  |  |
Accounts payable and accrued liabilities |  | 283 |  |
Fiduciary liabilities |  | 411 |  |
Current liabilities |  | 227 |  |
Long-term debt |  | 3,422 |  |
Non-current operating lease liabilities |  | 125 |  |
Deferred tax liabilities |  | 1,123 |  |
Non-current liabilities |  | 142 |  |
Total liabilities assumed |  | 5,733 |  |
Less: Fair value of redeemable noncontrolling interests |  | (103) |  |
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 |  | 5,825 |  |
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 |  | 109 |  |
Deferred and contingent consideration |  | 7 |  |
Class A ordinary shares issued |  | 0 |  |
Aggregate consideration transferred |  | 116 |  |
Assets acquired: |  |  |  |
Cash and cash equivalents |  | 3 |  |
Receivables |  | 3 |  |
Fiduciary assets |  | 6 |  |
Goodwill |  | 69 |  |
Other intangible assets: |  |  |  |
Operating lease right-of-use assets |  | 2 |  |
Current assets |  | 3 |  |
Non-current assets |  | 1 |  |
Total assets acquired |  | 138 |  |
Liabilities assumed: |  |  |  |
Accounts payable and accrued liabilities |  | 8 |  |
Fiduciary liabilities |  | 6 |  |
Current liabilities |  | 0 |  |
Long-term debt |  | 0 |  |
Non-current operating lease liabilities |  | 2 |  |
Deferred tax liabilities |  | 6 |  |
Non-current liabilities |  | 0 |  |
Total liabilities assumed |  | 22 |  |
Less: Fair value of redeemable noncontrolling interests |  | 0 |  |
Less: Fair value of nonredeemable noncontrolling interests |  | 0 |  |
Net assets acquired |  | 116 |  |
Other Acquisitions | Customer-related and contract-based |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | 50 |  |
Other Acquisitions | Tradenames |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | 0 |  |
Other Acquisitions | Technology and other |  |  |  |
Other intangible assets: |  |  |  |
Intangible assets |  | $ 1 |  |

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