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Derivative financial instruments - Information about Fair Values of Derivative Instruments in Consolidated Balance Sheet (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Mar. 31, 2025 | Sep. 30, 2025 | Dec. 31, 2024
Derivatives, Fair Value [Line Items] |  |  |
Asset derivatives, fair value |  | $ 253 | $ 255
Liability derivatives, fair value |  | 480 | 822
Reduction in estimated fair value of interest rate contracts in asset position | $ (686) | (379) |
Reduction in estimated fair value of interest rate contracts in liability position | $ (15) | (33) |
Fair value hedges: |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Asset derivatives, fair value |  | 192 | 206
Liability derivatives, fair value |  | 451 | 787
Fair value hedges: | Designated as Hedging Instrument |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Asset derivatives, fair value |  | 13 | 6
Liability derivatives, fair value |  | 0 | 3
Fair value hedges: | Not Designated as Hedging Instrument |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Asset derivatives, fair value |  | 48 | 43
Liability derivatives, fair value |  | 29 | 32
Interest rate swap agreements | Fair value hedges: | Designated as Hedging Instrument |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Asset derivatives, fair value |  | 12 | 2
Liability derivatives, fair value |  | 0 | 3
Commitments to sell real estate loans | Fair value hedges: | Designated as Hedging Instrument |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Asset derivatives, fair value |  | 1 | 4
Liability derivatives, fair value |  | 0 | 0
Commitments to sell real estate loans | Fair value hedges: | Not Designated as Hedging Instrument |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Asset derivatives, fair value |  | 28 | 39
Liability derivatives, fair value |  | 6 | 0
Commitments to originate real estate loans for sale | Fair value hedges: | Not Designated as Hedging Instrument |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Asset derivatives, fair value |  | 20 | 4
Liability derivatives, fair value |  | 23 | 32
Interest Rate Contracts | Fair value hedges: | Not Designated as Hedging Instrument |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Asset derivatives, fair value |  | 174 | 185
Liability derivatives, fair value |  | 435 | 769
Foreign exchange and other option and futures contracts | Fair value hedges: | Not Designated as Hedging Instrument |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Asset derivatives, fair value |  | 18 | 21
Liability derivatives, fair value |  | $ 16 | $ 18

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- Definition Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-7A Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 22 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483444/210-20-55-22 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 21 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483444/210-20-55-21 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 20 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483444/210-20-55-20 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 15 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483444/210-20-55-15 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483466/210-20-50-3 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 4D -Subparagraph (c)(2) -SubTopic 20 -Topic 860 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481326/860-20-50-4D + Details
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