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Fair Value Disclosures - Changes in Level 3 Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value, beginning balance | $ 363 | $ 337
Realized and Unrealized Gains (Losses),Assets | (1) | 2
Purchases, Assets | 161 | 474
Sales and Maturities, Assets | (145) | (456)
Issuances and other Settlements, Assets | 21 | 0
Transfers into Level 3, Assets | 0 | 12
Transfers out of Level 3, Assets | (32) | (6)
Assets measured at fair value, ending balance | 367 | 363
Total Net Unrealized Gains (Losses) Included in Earnings | 8 | 2
Liabilities measured at fair value, beginning balance | 4,431 | 279
Realized and Unrealized Gains (Losses), Liabilities | 712 | (35)
Purchases, Liabilities | 0 | 0
Sales and Maturities, Liabilities | 0 | 0
Issuances and other Settlements, Liabilities | 3,286 | 4,187
Transfers into Level 3, Liabilities | 0 | 0
Transfers out of Level 3, Liabilities | 0 | 0
Liabilities measured at fair value, ending balance | 8,429 | 4,431
Total Net Unrealized Gains (Losses) Included in Earnings | 729 | (35)
Other Assets [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value, beginning balance | 149 | 120
Assets measured at fair value, ending balance | 151 | 149
Other Liabilities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Liabilities measured at fair value, beginning balance | 129 | 180
Liabilities measured at fair value, ending balance | 0 | 129
Contingent consideration liabilities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Liabilities measured at fair value, beginning balance | 4,302 | 99
Realized and Unrealized Gains (Losses), Liabilities | $ 729 | $ (42)
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Business Combination, Contingent Consideration, Liability, Current | Business Combination, Contingent Consideration, Liability, Current
Purchases, Liabilities | $ 0 | $ 0
Sales and Maturities, Liabilities | 0 | 0
Issuances and other Settlements, Liabilities | 3,398 | 4,245
Transfers into Level 3, Liabilities | 0 | 0
Transfers out of Level 3, Liabilities | 0 | 0
Liabilities measured at fair value, ending balance | 8,429 | 4,302
Total Net Unrealized Gains (Losses) Included in Earnings | 729 | (42)
Investments [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value, beginning balance | 214 | 217
Realized and Unrealized Gains (Losses),Assets | (19) | 10
Purchases, Assets | 161 | 437
Sales and Maturities, Assets | (145) | (456)
Issuances and other Settlements, Assets | 21 | 0
Transfers into Level 3, Assets | 0 | 12
Transfers out of Level 3, Assets | (16) | (6)
Assets measured at fair value, ending balance | 216 | 214
Total Net Unrealized Gains (Losses) Included in Earnings | (10) | 10
Debt securities [Member] | Trading [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value, beginning balance | 7 | 42
Realized and Unrealized Gains (Losses),Assets | 0 | 3
Purchases, Assets | 0 | 35
Sales and Maturities, Assets | 0 | (1)
Issuances and other Settlements, Assets | 0 | 0
Transfers into Level 3, Assets | 0 | 0
Transfers out of Level 3, Assets | 0 | 0
Assets measured at fair value, ending balance | 7 | 7
Total Net Unrealized Gains (Losses) Included in Earnings | $ 0 | $ 3
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Nonoperating Income (Expense) | Nonoperating Income (Expense)
Debt securities [Member] | Trading [Member] | Previously Reported [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value, beginning balance | $ 79 |
Assets measured at fair value, ending balance |  | $ 79
Mutual Funds [Member] | Equity Securities Mutual Funds [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value, beginning balance | 0 |
Realized and Unrealized Gains (Losses),Assets | 0 |
Purchases, Assets | 136 |
Sales and Maturities, Assets | 0 |
Issuances and other Settlements, Assets | 0 |
Transfers into Level 3, Assets | 0 |
Transfers out of Level 3, Assets | 0 |
Assets measured at fair value, ending balance | 136 | 0
Total Net Unrealized Gains (Losses) Included in Earnings | 0 |
Loans [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value, beginning balance | 72 |
Realized and Unrealized Gains (Losses),Assets | (11) |
Purchases, Assets | 10 |
Sales and Maturities, Assets | (3) |
Issuances and other Settlements, Assets | 21 |
Transfers into Level 3, Assets | 0 |
Transfers out of Level 3, Assets | (16) |
Assets measured at fair value, ending balance | 73 | 72
Total Net Unrealized Gains (Losses) Included in Earnings | (10) |
Consolidated Variable Interest Entities [Member] | Loans [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value, beginning balance | 135 | 175
Realized and Unrealized Gains (Losses),Assets | (8) | 7
Purchases, Assets | 15 | 402
Sales and Maturities, Assets | (142) | (455)
Issuances and other Settlements, Assets | 0 | 0
Transfers into Level 3, Assets | 0 | 12
Transfers out of Level 3, Assets | 0 | (6)
Assets measured at fair value, ending balance | 0 | 135
Total Net Unrealized Gains (Losses) Included in Earnings | 0 | 7
Other Assets One [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Realized and Unrealized Gains (Losses),Assets | 18 | (8)
Purchases, Assets | 0 | 37
Sales and Maturities, Assets | 0 | 0
Issuances and other Settlements, Assets | 0 | 0
Transfers into Level 3, Assets | 0 | 0
Transfers out of Level 3, Assets | (16) | 0
Total Net Unrealized Gains (Losses) Included in Earnings | 18 | (8)
Other Liabilities One [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Realized and Unrealized Gains (Losses), Liabilities | (17) | 7
Purchases, Liabilities | 0 | 0
Sales and Maturities, Liabilities | 0 | 0
Issuances and other Settlements, Liabilities | (112) | (58)
Transfers into Level 3, Liabilities | 0 | 0
Transfers out of Level 3, Liabilities | 0 | 0
Total Net Unrealized Gains (Losses) Included in Earnings | $ 0 | $ 7
Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Nonoperating Income (Expense) | Nonoperating Income (Expense)

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- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2G -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2G Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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