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Derivative Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Derivative [Line Items] |  |  |
Notional amounts of derivative contracts entered into for trading account purposes | $ 27,277 |  | $ 26,977
Unrealized net loss recognized in other comprehensive income related to cash flow hedges | 359 |  |
Aggregate fair value of derivative financial instruments in asset position | 232 |  | 179
Collateral relating to net asset positions | 231 |  | 179
Clearinghouse Credit Facilities [Member] |  |  |
Derivative [Line Items] |  |  |
Amount of initial margin posted | 146 |  | 129
Interest Income [Member] |  |  |
Derivative [Line Items] |  |  |
Changes in Cash Flow Hedges Derivative Instruments At Fair Value Net | 87 | $ 59 |
Interest Rate Swap Agreements [Member] |  |  |
Derivative [Line Items] |  |  |
Increase decrease in net interest income due to interest rate swap agreements | $ 100 | $ 69 |
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest and Dividend Income, Operating | Interest and Dividend Income, Operating |
Interest Rate Swap Agreements [Member] | Maturity Period 2024 [Member] |  |  |
Derivative [Line Items] |  |  |
Unrealized net loss recognized in other comprehensive income related to cash flow hedges | $ 1 |  |
Interest Rate Swap Agreements [Member] | Maturity Period 2025 [Member] |  |  |
Derivative [Line Items] |  |  |
Unrealized net loss recognized in other comprehensive income related to cash flow hedges | 227 |  |
Interest Rate Swap Agreements [Member] | Maturity Period 2026 [Member] |  |  |
Derivative [Line Items] |  |  |
Unrealized net loss recognized in other comprehensive income related to cash flow hedges | 129 |  |
Interest Rate Swap Agreements [Member] | Maturity Period 2027 [Member] |  |  |
Derivative [Line Items] |  |  |
Unrealized net loss recognized in other comprehensive income related to cash flow hedges | 2 |  |
Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amounts of derivative contracts entered into for trading account purposes | 43,400 |  | 44,400
Foreign Exchange and Other Option and Futures Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amounts of derivative contracts entered into for trading account purposes | $ 1,700 |  | $ 1,500

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- Definition The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4H + Details
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- Definition Fair value, after offset of derivative liability, of 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, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 55 -Paragraph 9 -SubTopic 20 -Topic 210 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483444/210-20-55-9 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -SubTopic 20 -Topic 210 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483466/210-20-50-3 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 55 -Paragraph 10 -SubTopic 20 -Topic 210 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483444/210-20-55-10 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-8 + Details
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- Definition Indicates line item in statement of income or comprehensive income that includes gain (loss) from effective portion of derivative instrument reclassified from accumulated other comprehensive income (AOCI) into income. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4D -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4D + Details
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