Group Reporting Basis Reclassifications Group Reporting Basis Reclassifications [Member] Group Reporting Basis Reclassifications [Member] Debt and Equity Securities, FV-NI [Line Items] Debt and Equity Securities, FV-NI [Line Items] Precious metals contracts Commodity Contract [Member] Other HSBC affiliates Other Affiliates [Member] Summary of Credit Ratings of Credit Risk Related Guarantees Summary Of Credit Ratings Of Credit Risk Related Guarantees Table [Table Text Block] Summary Of Credit Ratings Of Credit Risk Related Guarantees Table [Table Text Block] Fair value option liabilities attributable to our own credit spread Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, after Tax and Reclassification Adjustment, Attributable to Parent Derivatives included in trading assets, amount offset Less: Gross amounts of cash collateral received subject to enforceable master netting agreements Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Cash, Offset Against Derivative Asset Award Timing Predetermined Award Timing Predetermined [Flag] Investment amortization expense Investment Program, Proportional Amortization Method, Applied, Amortization Expense Entity File Number Entity File Number Credit contracts Credit contracts Credit derivatives Credit Risk Contract [Member] Additional paid-in capital Additional Paid-in Capital [Member] Tabular List, Table Tabular List [Table Text Block] Trading assets Trading assets, excluding derivatives: Trading Assets [Member] Trading assets. Trading Assets and Liabilities Trading Assets And Liability Disclosure [Text Block] Trading assets and liability. Number of defendants requesting dismissal Number of Defendants Requesting Dismissal Number of Defendants Requesting Dismissal Number of updated forward-looking economic scenarios Number Of Updated Forward-looking Economic Scenarios Number Of Updated Forward-looking Economic Scenarios Standby letters of credit, Notional/Maximum Exposure to Loss Guarantor Obligations, Maximum Exposure, Undiscounted Asset-backed securities available-for-sale Debt Securities [Member] Noninterest bearing Noninterest-Bearing Deposit Liabilities, Domestic Measurement Basis [Axis] Measurement Basis [Axis] Adjustment to Compensation: Adjustment to Compensation [Axis] Related Party Transactions Related Party Transactions Disclosure [Text Block] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] HNAH HSBC North America Hnah [Member] HNAH. Fee Income from Contracts with Customers Revenue from Contract with Customer [Text Block] Financing Receivable Portfolio Segment [Domain] Financing Receivable Portfolio Segment [Domain] Financing Receivable Portfolio Segment [Domain] Recoveries Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Recovery Accrued interest receivables: Financing Receivable, before Allowance for Credit Loss [Abstract] Total mark-to-market on financial instruments designated at fair value Fair Value, Option, Changes in Fair Value, Gain (Loss) Available-for-sale amount after ten years Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Amortized Cost Derivatives included in trading liabilities, amount offset Less: Gross amounts of cash collateral posted subject to enforceable master netting agreements Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Offset Total loans, net Group 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Measurement Frequency [Axis] Measurement Frequency [Axis] Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-Sale [Table] Net change in unrealized gains (losses), net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Insider Trading Policies and Procedures [Line Items] Common stock, shares authorized (shares) Common Stock, Shares Authorized Hybrid Instruments Hybrid Instrument [Member] Fair Value, Recurring Fair Value, Recurring [Member] Reclassification, Type [Domain] Reclassification, Type [Domain] Cover [Abstract] Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Maximum Maximum [Member] Amortized Cost Securities held-to-maturity Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss 60 days or more past due Contractual Delinquency, 60 Days or More Past Due [Member] Contractual Delinquency, 60 Days or More Past Due [Member] Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Current Period Unrealized Gains (Losses) Still Held Included in Earnings Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss) Limited partnership investments(1) Variable Interest Entity, Not Primary Beneficiary, Limited Partnership Investments [Member] Variable Interest Entity, Not Primary Beneficiary, Limited Partnership Investments [Member] Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Financing Receivable, Credit Quality Indicator [Table] Financing Receivable, Credit Quality Indicator [Table] Credit Rating Source [Domain] External Credit Rating, Standard & Poor's [Domain] Market assumptions related to yields for comparable instruments Measurement Input, Comparability Adjustment [Member] Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Other assets: Other Assets [Member] Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Mortgage securitization outstanding loan purchase and sold Related Party, Whole Loan Securitization Program, Amount Outstanding Related Party, Whole Loan Securitization Program, Amount Outstanding Direct Costs Group Reporting Basis, Direct Operating Costs Group Reporting Basis, Direct Operating Costs Weighted-Average Term Extension / Payment Deferral (in years) Financing Receivable, Modified, Weighted Average Term Increase from Modification Income before income tax Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Entity Shell Company Entity Shell Company Actual Ratio Banking Regulation, Tier 1 Leverage Capital Ratio, Actual Revolving Loans Converted to Term Loans Financing Receivable, Excluding Accrued Interest, Revolving, Converted to Term Loan Federal funds sold and securities purchased under agreements to resell Securities purchased under agreements to resell Federal funds sold and securities purchased under agreements to resell Federal Funds Sold and Securities Purchased under Agreements to Resell Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] Discontinued hedged liability adjustments Hedged Liability, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Operating Segments Operating Segments [Member] Assets, Current Period Unrealized Gains (Losses) Still Held Included in Other Comprehensive Income (Loss) Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), OCI Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Total interest expense Interest Expense, Operating Options written Foreign Exchange Options Written [Member] Foreign Exchange Options Written [Member] Current - 59 days past due Contractual Delinquency, Current to 59 Days Past Due [Member] Contractual Delinquency, Current to 59 Days Past Due Document Fiscal Period Focus Document Fiscal Period Focus HSBC Technology & Services (USA) Inc. ("HTSU") Hsbc Technology And Services [Member] HSBC technology and services. Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Summary of Fair Value and Unpaid Principal Balance for Items Accounted for Under FVO Fair Value Option, Disclosures [Table Text Block] Award Timing Method Award Timing Method [Text Block] Litigation Case [Domain] Litigation Case [Domain] Nonaccrual Loans Financing Receivable, Excluding Accrued Interest, Nonaccrual Award Type Award Type [Axis] HSBC USA Parent Company [Member] Other commercial Other Commercial [Member] Other commercial. 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Debt: Proceeds from (Repayments of) Debt [Abstract] Net change in federal funds sold and securities purchased under agreements to resell Proceeds from (Payments for) Federal Funds Sold and Securities Purchased under Agreements to Resell, Net Unrealized Losses Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss Operating expenses: Noninterest Expense [Abstract] Disaggregation of Fee Income Disaggregation of Revenue [Table Text Block] Cash and due from banks Cash and Due from Banks Tax credits and other tax benefits Investment Program, Proportional Amortization Method, Elected, Income Tax Credit and Other Income Tax Benefit, before Amortization Expense Class of Financing Receivable [Domain] Class of Financing Receivable [Domain] Accruing Loans Contractually Past Due 90 Days or More Financing Receivable, Excluding Accrued Interest, 90 Days or More Past Due, Still Accruing Loss on sale of loans Gain (Loss) on Sale of Financing Receivable Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Standby letters of credit, Carrying Value Guarantor Obligations, Current Carrying Value Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Securities available-for-sale Debt Securities, Available-for-Sale, Accrued Interest, Before Allowance For Credit Loss Debt Securities, Available-for-Sale, Accrued Interest, Before Allowance For Credit Loss Weighted-Average Interest Rate Reduction Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification Pledged Status [Domain] Pledged Status [Domain] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date Restatement Determination Date Summary of Changes in the Liability for Off-balance Sheet Credit 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Designated as Hedging Instrument Designated as Hedging Instrument [Member] Asset-backed financing SPEs Variable Interest Entity, Not Primary Beneficiary, Asset-Backed Financing SPE [Member] Variable Interest Entity, Not Primary Beneficiary, Asset-Backed Financing SPE Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Capital Amount Banking Regulation, Risk-Weighted Assets, Actual Trust and investment management fees Asset Management [Member] Schedule of Guarantor Obligations [Table] Guarantor Obligation [Table] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Tier 1 capital ratio: Banking Regulation, Tier 1 Risk-Based Capital [Abstract] All Trading Arrangements All Trading Arrangements [Member] Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Compliance with 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cost of $34.3 billion and $31.7 billion, and includes $2.5 billion and $0.0 billion pledged to creditors) Fair Value Securities available-for-sale Debt Securities, Available-for-Sale, Excluding Accrued Interest Preferred stock, par value (usd per share) Preferred Stock, Par or Stated Value Per Share Subsequent Event Subsequent Event [Member] Net interest income Net interest income (expense), U.S. GAAP Consolidated Interest Income (Expense), Operating Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] PEO Total Compensation Amount PEO Total Compensation Amount Capital Amount Banking Regulation, Tier 1 Risk-Based Capital, Actual Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Repurchase Agreements and Similar Transactions, Maturity Periods [Axis] Repurchase Agreements and Similar Transactions, Maturity Periods [Axis] Derivative Liabilities Derivative Liability, Subject to Master Netting Arrangement, before Offset Equity Components [Axis] Equity Components [Axis] Three years prior to current year Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year Standby Letters of Credit Standby Letters of Credit [Member] Collateral-dependent loans Financing Receivable, Repayment Through Operation Or Sale Of Collateral, Collateral Financing Receivable, Repayment Through Operation Or Sale Of Collateral, Collateral Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Servicing and other fees from HSBC affiliates: Servicing And Other Fees [Abstract] Servicing and other fees. 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Instruments Held For Other Purposes [Table Text Block] Repayment of long-term debt Repayments of Long-Term Debt Entity Interactive Data Current Entity Interactive Data Current Group Reporting Basis, Type [Axis] Group Reporting Basis, Type [Axis] Group Reporting Basis, Type 30 - 89 Days Financing Receivables, 30 to 89 Days Past Due [Member] Financing Receivables, 30 to 89 Days Past Due [Member] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Financing Receivable, Modified [Line Items] Financing Receivable, Modified [Line Items] Interest income: Interest and Dividend Income, Operating [Abstract] Total operating expenses Total operating expenses, U.S. GAAP Consolidated Noninterest Expense Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Allowance for Credit Losses Allowance for Credit Losses [Text Block] Deposits Interest Expense, Deposits Other revenues: Noninterest Income [Abstract] CC CC Segment [Member] CC Segment Valuation allowance SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount Fixed Rate Note Maturing June 2030 Fixed Rate Note Maturing June 2030 [Member] Fixed Rate Note Maturing June 2030 Entity Central Index Key Entity Central Index Key Credit derivatives, Notional/Maximum Exposure to Loss Notional Credit Derivative, Maximum Exposure, Undiscounted PEO Name PEO Name Total income Revenues Gain (Loss) Recognized in Income on Derivatives Mark-to-market on related derivatives Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Summary of Credit Quality Indicator Financing Receivable Credit Quality Indicators [Table Text Block] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate 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Other liabilities Other Liabilities [Member] Fair Value as of Grant Date Award Grant Date Fair Value Four years prior to current year Financing Receivable, Excluding Accrued Interest, Year Five, Originated, Four Years before Current Fiscal Year Salaries and employee benefits Labor and Related Expense Related Party Transaction [Line Items] Related Party Transaction [Line Items] Document Quarterly Report Document Quarterly Report Securities available-for-sale aggregate fair value of investment one year or less Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months Actual Ratio Banking Regulation, Tier 1 Risk-Based Capital Ratio, Actual Long-term debt Long-Term Debt, Fair Value Quantitative Information about Recurring Fair Value Measurement of Assets and Liabilities Classified as Level 3 Fair Value Measurement Inputs and Valuation Techniques [Table Text Block] Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Summary of 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Unrealized Gains Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax All Award Types Award Type [Domain] Gain (Loss) Recognized in AOCI on Derivatives Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax Equity Awards Adjustments Equity Awards Adjustments [Member] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Compensation Amount Outstanding Recovery Compensation Amount Argentine Tax Authority Argentine Tax Authority [Member] Argentine Tax Authority Derivatives liability Derivative Financial Instruments, Liabilities [Member] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Foreign exchange contracts Foreign Exchange Contract [Member] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Fair Value Estimate of Fair Value Measurement [Member] Group Reporting Basis, Type [Domain] Group Reporting Basis, Type [Domain] Group Reporting Basis, Type [Domain] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Trading Liabilities Trading Liabilities [Member] Fair Value, Option, Quantitative Disclosures [Line Items] Fair Value, Option, Quantitative Disclosures [Line Items] Financing Receivable, Past Due [Line Items] Financing Receivable, Past Due [Line Items] Low income housing investments, variable interests held reported as assets, carrying value Investment, Proportional Amortization Method, Elected, Amount Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Hedged Liability, Statement of Financial Position [Extensible Enumeration] Hedged Liability, Statement of Financial Position [Extensible Enumeration] Financial Instruments [Domain] Types of Financial Instruments [Domain] Financial Instruments [Domain] Investment securities OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax Assets, Purchases Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Other financial assets measured at amortized cost Other Financial Assets, Measured At Cost. Accrued Interest, Before Allowance For Credit Loss Other Financial Assets, Measured At Cost. Accrued Interest, Before Allowance For Credit Loss $50,000,000 Zero Coupon Callable Accreting Notes due January 29, 2043 Zero Coupon Callable Accreting Notes due January 29, 2043 [Member] Zero Coupon Callable Accreting Notes due January 29, 2043 [Member] Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Total Realized/Unrealized Gains (Losses) Included in Other Comprehensive Income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Other Comprehensive Income (Loss) Forecast, Quarter ended June 30, 2027 Forecast, Quarter ended June 30, 2027 [Member] Forecast, Quarter ended June 30, 2027 Total income Group Reporting Basis Operating Income Net Group Reporting Basis Operating Income Net Minimum Minimum [Member] Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table] Banking Regulation, Regulatory Capital Requirement, Compliance [Table] Net interest income after provision for credit losses Interest Income (Expense), after Provision for Loan Loss Loans Financing Receivable, Accrued Interest, before Allowance for Credit Loss Accounts, Notes, Loans and Financing Receivable [Line Items] Fair Value, Assets and Liabilities Measured on a Nonrecurring Basis [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Company Selected Measure Name Company Selected Measure Name Fair Value Measurement [Domain] Fair Value Measurement [Domain] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Held-to-maturity yield after ten years (percent) Debt Securities, Held-to-Maturity, Maturity, Rolling after 10 Years, Weighted Average Yield Options written Commodities, Equities and Precious Metals Options Written [Member] Commodities, Equities and Precious Metals Options Written [Member] Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Guarantee Arrangements, Pledged Assets and Repurchase Agreements Commitments and Contingencies Disclosure [Text Block] Derivative assets (liability Derivative Assets (Liabilities), at Fair Value, Net Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Fixed Rate Note Maturing May 2035 Fixed Rate Note Maturing May 2035 [Member] Fixed Rate Note Maturing May 2035 Derivative [Table] Derivative [Table] Extended loans and lines of credit Loan And Lease Receivable Extended Loan And Line Of Credit Facility Loan and lease receivable extended loan and line of credit facility. Domestic deposits: Deposits, Domestic [Abstract] Entity Small Business Entity Small Business Total fair value within one year Debt Securities, Held-to-Maturity, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value ECL Estimates, Forecast Period [Axis] ECL Estimates, Forecast Period [Axis] ECL Estimates, Forecast Period [Axis] Preferred stock, shares outstanding (shares) Preferred Stock, Shares Outstanding Document Transition Report Document Transition Report Group Reporting Basis Adjustments Group Reporting Basis Adjustments [Member] Group Reporting Basis Adjustments [Member] Structured notes Structured Note [Member] Structured Note [Member] Carrying Value and Estimated Fair Value of Financial Instruments Fair Value Disclosure of Asset and Liability Not Measured at Fair Value [Table Text Block] Long-term debt Long-Term Debt [Member] Long-term debt designated under fair value option Long Term Debt Fair Value Option Disclosure This element represents the portion of long term debt that the entity has elected to value at fair value under the fair value option. Preferred stock outstanding Preferred Stock, Value, Outstanding Underlying Securities Award Underlying Securities Amount Account services Bank Servicing [Member] Gross realized gains Debt Securities, Available-for-Sale, Realized Gain Loans Held for Sale Loans Held For Sale Disclosure [Text Block] Loans held for sale. Equity Component [Domain] Equity Component [Domain] Document Period End Date Document Period End Date HSBC Bank plc HSBC Bank Plc [Member] HSBC Bank Plc [Member] Sell-protection Credit Derivatives Sell-protection credit derivative positions Sell Protection Credit Derivatives [Member] Sell-protection credit derivatives. Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Aggregate fair value of all derivative instruments with credit-risk related contingent features Derivative, Net Liability Position, Aggregate Fair Value Foreign bonds Foreign debt securities Debt securities issued by foreign entities Foreign Debt Securities [Member] Foreign Debt Securities [Member] Net change in loans held for sale: Payment for Origination and Purchase, Loan, Held-for-Sale [Abstract] Less: Gross amounts of financial instrument collateral received not offset Derivative Asset, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Option adjusted discounted cash flows Option Adjusted Discounted Cash Flows [Member] Option adjusted discounted cash flows. Document Type Document Type Level 3 Fair Value, Inputs, Level 3 [Member] Name Outstanding Recovery, Individual Name Loss Contingencies [Table] Loss Contingencies [Table] Total accrued interest receivables Interest Receivables, Before Allowance For Credit Loss Interest Receivables, Before Allowance For Credit Loss Product and Service [Axis] Product and Service [Axis] Revolving loans Financing Receivable, Excluding Accrued Interest, Revolving, Writeoff Other revenues Total fee income from contracts with customers Revenue from Contract with Customer, Excluding Assessed Tax Litigation Status [Domain] Litigation Status [Domain] Common equity: Common Shareholders Equity [Abstract] Common Shareholders Equity Abstract. Statistical Measurement [Axis] Statistical Measurement [Axis] Estimated repurchase liability Loss Contingency Accrual One year prior to current year Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff Fair Value Measurements, Recurring, Valuation Techniques [Line Items] Fair Value Measurement Inputs and Valuation Techniques [Line Items] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Tier 1 leverage ratio: Banking Regulation, Leverage Ratio [Abstract] Credit risk component, total Fair Value, Option, Credit Risk, Gains (Losses), Net Fair Value, Option, Credit Risk, Gains (Losses), Net Total fair value after one but within five years Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Fair Value Financial standby letters of credit, net of participations Financial Standby Letter of Credit [Member] Total other comprehensive income (loss) Other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Guarantor Obligations, Nature [Domain] Guarantor Obligations, Nature [Domain] Modified loans, past due Financing Receivable, Excluding Accrued Interest, Modified, after 12 Months GDP growth rate (year-over-year) (in percent) GDP Growth Rate GDP Growth Rate Fair Value Over (Under) Unpaid Principal Balance Fair Value Over (Under) Unpaid Principal Balance Fair Value Over (Under) Unpaid Principal Balance Level 1 Fair Value, Inputs, Level 1 [Member] Amount outstanding under the loan agreement Long-Term Line of Credit Total debt Debt And Deposit Liabilities Debt And Deposit Liabilities Schedule of Related Party Transactions, by Related Party [Table] Related Party Transaction [Table] Realized Gains and Losses on Investment Securities Transactions Attributable to Available-for-Sale Securities Schedule of Realized Gain (Loss) [Table Text Block] Index credit derivatives Credit Index Product [Member] Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Loans modified Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount Greater Than One Year Maturity Greater than One Year [Member] Maturity Greater than One Year [Member] Trading assets (includes $2.8 billion and $3.5 billion pledged to creditors) Trading assets Trading Assets Trading Assets Operating Statistics [Line Items] Operating Statistics [Line Items] Operating Statistics [Line Items ] Loans held for sale (includes $0.7 billion and $0.6 billion designated under fair value option) Total loans held for sale Loans held for sale Financing Receivable, Held-for-Sale Commercial loans Commercial Loan [Member] Consolidation Items [Domain] Consolidation Items [Domain] Derivative Liability, Statement of Financial Position [Extensible Enumeration] Derivative Liability, Statement of Financial Position [Extensible Enumeration] Summary of Accrued Interest Receivables Summary Of Accrued Interest Receivables [Table Text Block] Summary of Accrued Interest Receivables [Table Text Block] Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Variable Interest Entity, Not Primary Beneficiary Variable Interest Entity, Not Primary Beneficiary [Member] Offsetting Assets and Liabilities Offsetting Assets And Liabilities [Table Text Block] Offsetting Assets and Liabilities [Table Text Block] Mortgage Securitization Activity Related Litigation Mortgage Securitization Activity Related Litigation [Member] Mortgage securitization activity related litigation. Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Axis] Financial Instruments Owned and Pledged as Collateral [Line Items] Financial Instruments Owned and Pledged as Collateral [Line Items] Derivatives, net, Total Realized/Unrealized Gains (Losses) Included in Earnings Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Earnings Total commodities, equities and precious metals Commodity and Equity Contract [Member] Commodity and Equity Contract [Member] HSBC Bank USA Subsidiaries [Member] Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items] Capital Amounts and Ratios in Accordance With Current Banking Regulations Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table Text Block] Total fair value after five but within ten years Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 5 through 10 Years, Fair Value Loans Loans, net Total Loans receivable from related parties Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss Securities sold under repurchase agreements, Net Amounts Presented in the Balance Sheet Securities Sold under Agreements to Repurchase Gross Unrealized Losses and Related Fair Value Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table Text Block] Expiration Date Trading Arrangement Expiration Date Well-Capitalized Ratio Banking Regulation, Common Equity Tier 1 Risk-Based Capital Ratio, Well Capitalized, Minimum Short Term Lending Short Term Lending [Member] Short Term Lending Securities held-to-maturity, allowance for credit losses Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Excluding Accrued Interest Properties and equipment, net Property, Plant and Equipment, Net Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Entity Current Reporting Status Entity Current Reporting Status Available-for-sale yield within one year (percent) Debt Securities, Available-for-Sale, Maturity, Rolling within One Year, Weighted Average Yield Receivables [Abstract] Receivables [Abstract] Derivative [Line Items] Derivative [Line Items] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Consolidated Entities [Domain] Consolidated Entities [Domain] Combination Multiple Modification Types [Member] Multiple Modification Types Loans Loans [Member] Derivative liability before netting Derivative Liability, Gross Liability Including Not Subject to Master Netting Arrangement Financial Instrument [Axis] Financial Instrument [Axis] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Executive Category: Executive Category [Axis] Fixed Rate Note Maturing November 2026 to November 2032 Fixed Rate Note Maturing November 2026 to November 2032 [Member] Fixed Rate Note Maturing November 2026 to November 2032 Exchange traded derivatives as a percentage of total derivative liabilities (less than) Exchange Traded Derivatives as a Percentage of Total Derivative Liabilities Exchange Traded Derivatives as a Percentage of Total Derivative Liabilities Securities available-for-sale gross unrealized losses greater than one year Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Other income (loss) Other Operating Income (Expense), Net Market comparables and internal assumptions Valuation, Market Approach [Member] Interest expense Interest Expense, Operating and Nonoperating Issuance of long-term debt Proceeds from Issuance of Long-Term Debt Current Fiscal Year End Date Current Fiscal Year End Date Securities available-for-sale gross unrealized losses one year or less Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Total deposits Deposits Total deposits, U.S. GAAP Consolidated Deposits Whole loan securitization Related Party, Whole Loan Securitization Program, Amounts of Transaction Related Party, Whole Loan Securitization Program, Amounts of Transaction Tax on amortization of net unrealized losses on securities transferred from available-for-sale to held-to-maturity realized in net income (loss) (less than) OCI, Debt Securities, Available-for-Sale, Transfer to Held-to-Maturity, Adjustment from AOCI for Amortization of Gain (Loss), Tax Foreign deposits - interest bearing Interest-Bearing Deposit Liabilities, Foreign Federal Home Loan Bank stock Federal Home Loan Bank Stock Carrying Value and Contractual Amounts of our Sell Protection Credit Derivatives and Major Off-Balance Sheet Guarantee Arrangements Schedule of Guarantor Obligations [Table Text Block] Derivative liability Derivative liabilities Derivative Liability Other expenses Other Noninterest Expense Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Pass rated Pass [Member] Loan Restructuring Modification [Axis] Loan Restructuring Modification [Axis] Interest rate contracts Interest Rate Contract [Member] Gain (loss) on instruments designated at fair value and related derivatives Gain (loss) on instruments designated at fair value and related derivatives Gain (loss) on Instruments Designated at Fair Value and Related Derivatives [Member] Gain (loss) on Instruments Designated at Fair Value and Related Derivatives [Member] Principal Forgiven (in millions) Financing Receivable, Excluding Accrued Interest, Modified, Increase (Decrease) from Modification Assets and Liabilities Recorded at Fair Value on a Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Number of equal borrowings Number of Borrowings Number of Borrowings Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Summary of Past Due Status of Loans Financing Receivable, Past Due [Table Text Block] Net cash provided by financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Investment Grade External Credit Rating, Investment Grade [Member] Measure: Measure [Axis] Valuation Approach and Technique [Axis] Valuation Approach and Technique [Axis] Fair value of derivative assets and liabilities Derivative, Fair Value, Net Additional commitments for loans modified Financing Receivable, Modified, Commitment To Lend Financing Receivable, Modified, Commitment To Lend Total fair value after five but within ten years Debt Securities, Held-to-Maturity, Maturity, Allocated and Single Maturity Date, Rolling after 5 through 10 Years, Fair Value Investment Proportional Amortization Method Elected Statement Of Financial Position Extensible Enumeration Not Disclosed Flag Investment Proportional Amortization Method Elected Statement Of Financial Position Extensible Enumeration Not Disclosed Flag Investment Proportional Amortization Method Elected Statement Of Financial Position Extensible Enumeration Not Disclosed Flag Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Total capital ratio: Banking Regulation, Total Capital [Abstract] Held-to-maturity amount within one year Debt Securities, Held-to-Maturity, Amortized Cost Excluding Accrued Interest, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, Rolling within One Year Total fair value after ten years Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Entity Tax Identification Number Entity Tax Identification Number Discounted cash flows Valuation Technique, Discounted Cash Flow [Member] Three years prior to current year Financing Receivable, Excluding Accrued Interest, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff Variable Interests Held by Us and Our Maximum Exposure to Loss Rising From Our Involvements in Those VIEs Schedule Of Additional Information On Unconsolidated Vies [Table Text Block] Schedule Of Additional Information On Unconsolidated Vies [Table Text Block] Derivatives, net Derivatives Derivative [Member] Common stock, shares issued (shares) Common Stock, Shares, Issued Forecast, Quarter ended June 30, 2026 Forecast, Quarter ended June 30, 2026 [Member] Forecast, Quarter ended June 30, 2026 Derivative Asset, Statement of Financial Position [Extensible Enumeration] Derivative Asset, Statement of Financial Position [Extensible Enumeration] Dividend income on equity securities held for trading Dividend Income, Equity Securities, Operating Asset Pledged as Collateral with Right Asset Pledged as Collateral with Right [Member] Allowance for Loan and Lease Losses [Roll Forward] Allowance for Loan and Lease Losses [Roll Forward] Total, Carrying Value Credit Risk Derivatives And Guarantor Obligations, Current Carrying Value Credit Risk Derivatives And Guarantor Obligations, Current Carrying Value Trading Arrangement: Trading Arrangement [Axis] Total Shareholder Return Amount Total Shareholder Return Amount Total Assets Held by Unconsolidated VIEs Variable Interest Entity, Nonconsolidated, Total Assets Variable Interest Entity, Nonconsolidated, Total Assets Loss Contingencies [Line Items] Loss Contingencies [Line Items] Total Realized/Unrealized Gains (Losses) Included in Earnings Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings Security Exchange Name Security Exchange Name Components Of Gain On Instruments At Fair Value And Related Derivatives [Line Items] Components Of Gain On Instruments At Fair Value And Related Derivatives [Line Items] Components Of Gain On Instruments At Fair Value And Related Derivatives [Line Items] Securities purchased under agreements to resell, Net amounts Presented in the Balance Sheet Securities Purchased under Agreements to Resell Loans sold to third parties Proceeds from Sale, Loan, Held-for-Investment Previously reported in other income (loss) Reclassification, Other [Member] Maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Components of Gain on Instruments at Fair Value and Related Derivatives Components Of Gain On Instruments At Fair Value And Related Derivatives Table [Table Text Block] Components Of Gain On Instruments At Fair Value And Related Derivatives Table [Table Text Block] Asset Class [Domain] Asset Class [Domain] Assets, Total Realized/Unrealized Gains (Losses) Included in Earnings Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings Reclassification, Type [Axis] Reclassification, Type [Axis] Statement [Line Items] Statement [Line Items] Carrying amount of hedged items Hedged Asset, Fair Value Hedge Securities Interest Income Securities Interest income on securities classified either as available-for-sale or held-to-maturity and includes: (a) interest and dividends earned on all securities and (b) amortization and accretion (as applicable) of discounts and premiums, if any. Excludes trading securities. Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Fair Value Measurements, Recurring, Valuation Techniques [Table] Fair Value Measurement Inputs and Valuation Techniques [Table] Credit facilities Credit Facilities [Member] Credit Facilities [Member] Common stock Common Stock [Member] Issuances Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Issuances Securities held-to-maturity Debt Securities, Held-to-Maturity, Accrued Interest, before Allowance for Credit Loss Fixed Rate Note Maturing March 2028 Fixed Rate Note Maturing March 2028 [Member] Fixed Rate Note Maturing March 2028 Trading liabilities Trading Liabilities Net change in cash and due from banks and interest bearing deposits with banks Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Securities purchased under agreements to resell, Gross Amounts Offset in the Balance Sheet Security Purchased under Agreement to Resell, Subject to Master Netting Arrangement, Liability Offset Guarantor Obligations [Line Items] Guarantor Obligations [Line Items] Statistical Measurement [Domain] Statistical Measurement [Domain] Swaps, futures and forwards Interest Rate Swaps, Futures and Forwards [Member] Interest Rate Swaps, Futures and Forwards Securities Securities Disclosure [Text Block] Securities. Securities available-for-sale, amortized cost Amortized Cost Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss Interest income that was recorded on nonaccrual loans and included in interest income during the period Financing Receivable, Nonaccrual, Interest Income Related Party Transaction [Axis] Related Party Transaction [Axis] Asset Class [Axis] Asset Class [Axis] Valuation Approach and Technique [Domain] Valuation Approach and Technique [Domain] Assets, Total Realized/Unrealized Gains (Losses) Included in Other Comprehensive Income (Loss) Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) Fixed Rate Note Maturing March 2029 Fixed Rate Note Maturing March 2029, Issued During First Quarter 2026 [Member] Fixed Rate Note Maturing March 2029, Issued During First Quarter 2026 Nonaccrual Loans With No Allowance For Credit Losses Financing Receivable, Excluding Accrued Interest, Nonaccrual, No Allowance Pledged Status [Axis] Pledged Status [Axis] Loans And Lines Of Credit Loans And Lines Of Credit [Member] Loans And Lines Of Credit Derivatives, net, Transfers into Level 3 Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3 Unrealized Losses Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Non-income-tax-related gains and other returns Investment Program, Proportional Amortization Method, Applied, Non-Income-Tax-Related Activity and Other Return Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Amount of additional collateral to be posted upon downgrade Additional Collateral, Aggregate Fair Value Securities purchased under agreements to resell, Gross Amounts Recognized Security Purchased under Agreement to Resell, Subject to Master Netting Arrangement, before Offset Summary of Related Party Transactions Summary Of Related Party Financial Information Table [Table Text Block] Summary Of Related Party Financial Information Table [Table Text Block] Short-term borrowings Short-term borrowings Short-Term Debt Hybrid instruments, structured deposits, Fair Value Deposits, Fair Value Disclosure Unrealized Gains Debt Securities, Held-to-Maturity, Accumulated Unrecognized Gain Measurement Input Type [Domain] Measurement Input Type [Domain] Affiliates Affiliated Entity Affiliated Entity [Member] Assets, Current Period Unrealized Gains (Losses) Still Held Included in Earnings Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss) Assets and Liabilities Recorded at Fair Value on a Non Recurring Basis Fair Value Measurements, Nonrecurring [Table Text Block] Total Charge-offs Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff CIB CIB Segment [Member] CIB Segment Measurement of ECL Measurements [Line Items] Measurement of ECL Measurements [Line Items] Measurement of ECL Measurements [Line Items] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Originations, net of collections Origination (Proceeds From Collection) Of Finance Receivables Origination (Proceeds From Collection) Of Finance Receivables Securities purchased under agreements to resell, Net amount Security Purchased under Agreement to Resell, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Fair Value Measurements, Nonrecurring [Table] Accounts and Financing Receivables [Table] Retained Earnings Note Disclosure [Abstract] Retained Earnings Note Disclosure [Abstract] Income (Expense): Interest Income (Expense), Operating [Abstract] Net unrealized gains (losses) arising during the period, net of tax OCI, before Reclassifications, Net of Tax, Attributable to Parent Derivative Instruments, Gain (Loss) [Line Items] Derivative Instruments, Gain (Loss) [Line Items] Hedging Designation [Domain] Hedging Designation [Domain] Total liabilities and equity Liabilities and Equity Fixed rate long-term debt, Fair Value Fixed Rate Debt Accounted For Under Fair Value Option Fixed-rate debt accounted for under fair value option. Pension and postretirement benefit liability Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Derivative Instruments, Gain (Loss) by Hedging Relationship, by Income Statement Location, by Derivative Instrument Risk [Table] Derivative Instruments, Gain (Loss) [Table] Schedule of Gains and Losses on Cash Flow Hedging Instruments Schedule Of Cash Flow Hedge Instruments Statement Of Financial Position Location [Table Text Block] Schedule Of Cash Flow Hedge Instruments Statement Of Financial Position Location Table [Text Block] Credit card fees, net Credit Card [Member] Other non-fee revenue Other Non-Fee Revenues Other Non-Fee Revenues Reclassification adjustment for (gains) losses realized in net income (loss), net of tax Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent Schedule of Credit Derivatives [Table] Credit Derivative [Table] Collateral accepted under security resale agreements, fair value Securities Purchased under Agreements to Resell, Fair Value of Collateral Goodwill Group Reporting Basis Goodwill Group Reporting Basis Goodwill Available-for-sale yield after ten years (percent) Debt Securities, Available-for-Sale, Maturity, Rolling after 10 Years, Weighted Average Yield Securities sold under repurchase agreements, Gross Amounts Offset in the Balance Sheet Security Sold under Agreement to Repurchase, Subject to Master Netting Arrangement, Asset Offset Current year Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year Pay vs Performance Disclosure [Line Items] Well-Capitalized Ratio Banking Regulation, Tier 1 Leverage Capital Ratio, Well Capitalized, Minimum U.S. Government agency issued or guaranteed US Government Agencies Debt Securities [Member] 90+ Days Financial Asset, Equal to or Greater than 90 Days Past Due [Member] Liabilities: Liabilities: Liabilities [Abstract] Loans sold, carrying value Financing Receivable, Sale Commercial loans held for sale Commercial Loans Held for Sale [Member] Commercial Loans Held for Sale [Member] Securities purchased under resale agreements, Gross Amounts Not Offset in the Balance Sheet Security Purchased under Agreement to Resell, Subject to Master Netting Arrangement, Collateral, Obligation to Return Assets Not Offset Security Purchased under Agreement to Resell, Subject to Master Netting Arrangement, Collateral, Obligation to Return Assets Not Offset Loans modified, subsequently default Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Default Net (charge-offs) recoveries Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff (Recovery) Precious metals trading Precious Metals Inventory, Trading, Fair Value Disclosure Precious Metals Inventory, Trading, Fair Value Disclosure Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Net amount of derivative asset Derivative Asset Net Represents the amount of derivative assets net of assets that does not meet applicable offsetting guidance and cash and non-cash collateral under master netting arrangements. Gain (Loss) on Hedged Items Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge Retained Earnings and Regulatory Capital Requirements Regulatory Capital Requirements under Banking Regulations [Text Block] Schedule of Variable Interest Entities [Table] Variable Interest Entity [Table] Loans Held for Sale Loans Held For Sale Table [Table Text Block] Loans Held For Sale Table [Table Text Block] Two years prior to current year Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Company Selected Measure Amount Company Selected Measure Amount Prior Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year, Writeoff Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Well-Capitalized Ratio Banking Regulation, Tier 1 Risk-Based Capital Ratio, Well Capitalized, Minimum Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Measurement Input Type [Axis] Measurement Input Type [Axis] Name Measure Name Assets, Issuances Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Issuances Net change in deposits Increase (Decrease) in Deposits Proceeds from paydowns and maturities of securities available-for-sale Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-Sale Equity / Equity and Equity / Index correlation Measurement Input, Equity/Equity and Equity/Index Correlation [Member] Measurement Input, Equity/Equity and Equity/Index Correlation [Member] Options purchased Commodities, Equities and Precious Metals Options Purchased [Member] Commodities, Equities and Precious Metals Options Purchased [Member] Derivatives, net, Total Realized/Unrealized Gains (Losses) Included in Other Comprehensive Income Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Gain (Loss) Included in Other Comprehensive Income (Loss) Derivative liability netting adjustment Derivative Liability, Subject to Master Netting Arrangement, Gross Asset and Collateral, Right to Reclaim Cash, Offset Long-term debt (includes $7.6 billion and $8.3 billion designated under fair value option) Long-term debt Long-term debt Long-Term Debt Indirect Costs Group Reporting Basis, Indirect Operating Costs Group Reporting Basis, Indirect Operating Costs Total assets Total assets, U.S. GAAP Consolidated Assets Assets Other consumer Consumer, Other [Member] Financing Receivable, Credit Quality Indicator [Line Items] Financing Receivable, Credit Quality Indicator [Line Items] Total liabilities Financial And Nonfinancial Liabilities, Fair Value Disclosure, Net Financial And Nonfinancial Liabilities, Fair Value Disclosure, Net Credit Derivatives Contract Type [Axis] Credit Derivatives Contract Type [Axis] Unemployment rate (quarterly average) (in percent) Unemployment Rate Unemployment Rate Short-term financial assets, net of allowance for credit losses Short Term Financial Assets, Net Of Allowance For Credit Losses Short Term Financial Assets, Net Of Allowance For Credit Losses External Credit Rating By Grouping [Domain] External Credit Rating by Grouping [Domain] Carrying / Fair Value Credit Risk Derivative Liabilities, at Fair Value Cash flows from operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Profit (loss) before income tax Group Reporting Basis Profit (Loss) Before Income Tax Expense Group Reporting Basis Profit (Loss) Before Income Tax Expense Sales and collections of loans held for sale Proceeds from Sale and Collection, Loan, Held-for-Sale Reclassification Reclassification, Segmentation Basis Change [Member] Available-for-sale amount after one but within five years Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Amortized Cost Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Securities held-to-maturity, fair value Fair Value Debt Securities, Held-to-Maturity, Fair Value Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-Sale [Line Items] Level 2 Fair Value, Inputs, Level 2 [Member] Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] OCI, Cash Flow Hedge, Reclassification for Discontinuance, Statement of Income or Comprehensive Income [Extensible Enumeration] OCI, Cash Flow Hedge, Reclassification for Discontinuance, Statement of Income or Comprehensive Income [Extensible Enumeration] Related Party Related Party [Member] Asset Pledged as Collateral Asset Pledged as Collateral [Member] Derivatives Derivative Asset (Liability) Net, Measurement Input Net position, Carrying/Fair Value Credit Risk Derivatives, at Fair Value, Net Residential mortgages Residential Mortgage [Member] Document Information [Table] Document Information [Table] PEO PEO [Member] Assets, Transfers Into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 Securities, trading Debt Securities, Trading Capital Amount Banking Regulation, Tier 1 Leverage Capital, Actual Distribution of Maturities of Debt Securities with the Approximate Yield of the Portfolio Investments Classified by Contractual Maturity Date [Table Text Block] Discontinued hedged asset adjustments Hedged Asset, Discontinued Fair Value Hedge, Cumulative Increase (Decrease) Home equity mortgages Home Equity Backed Securities [Member] Home equity backed securities. Long-term debt Debt [Member] Total fair value within one year Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value Capital Amount Banking Regulation, Common Equity Tier 1 Risk-Based Capital, Actual Support services from HSBC affiliates: Support Services [Abstract] Support services. Retained earnings Retained Earnings [Member] Overnight and Continuous Maturity Overnight and Continuous [Member] Maturity Overnight and Continuous [Member] Cash and due from banks and interest bearing deposits with banks at beginning of period Cash and due from banks and interest bearing deposits with banks at end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Income Statement [Abstract] Income Statement [Abstract] Financial and performance standby letters of credit Guarantee Obligations [Member] Derivative asset Derivative assets Derivative Asset HSBC Securities Hsbc Securities [Member] HSBC Securities. Securities available-for-sale aggregate fair value of investment greater than one year Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer Not Designated as Hedging Instrument, Other Not Designated as Hedging Instrument, Economic Hedge [Member] Performance standby letters of credit, net of participations Performance Guarantee [Member] Deposits designated under fair value option Interest Bearing Deposits Domestic Fair Value Option Disclosure Interest bearing deposits domestic fair value option disclosure. Other Non-affiliated Entity [Member] Non-affiliated Entity [Member] Fair Value, Nonrecurring Fair Value, Nonrecurring [Member] Financing Receivable, Modified [Table] Financing Receivable, Modified [Table] Provision charged (credited) to income Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) Federal Reserve Bank stock Federal Reserve Bank Stock Product and Service [Domain] Product and Service [Domain] Securities available-for-sale: Debt Securities, Available-for-Sale [Abstract] Transfers Out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers out of Level 3 Derivatives, net, Transfers out of Level 3 Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers out of Level 3 Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Total liabilities Liabilities, Fair Value Disclosure Total Notional value of derivative contracts 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underlying collateral Third Party Appraisal [Member] Third party appraisal. Option pricing model Valuation Technique, Option Pricing Model [Member] Arrangement Duration Trading Arrangement Duration Average Life (in years) Average Term of Credit Risk Derivatives Criticized Criticized [Member] Total deposits Group Reporting Basis Deposits Group Reporting Basis Deposits Segments [Axis] Segments [Axis] Risk weighted assets: Banking Regulation, Risk-Based Information [Abstract] Fair Value by Liability Class [Domain] Fair Value by Liability Class [Domain] Local Phone Number Local Phone Number Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Charge-off of accrued interest receivables Financing Receivable, Accrued Interest, Writeoff Other, net Payment for (Proceeds from) Other Investing Activity Credit Derivatives Contract Type [Domain] Credit Derivatives Contract Type [Domain] Amortization of net unrealized (gains) losses on securities transferred from available-for-sale to held-to-maturity realized in net income, net of tax OCI, Debt Securities, Available-for-Sale, Transfer to Held-to-Maturity, Adjustment from AOCI for Amortization of Gain (Loss), after Tax Up to 30 Days Maturity Less than 30 Days [Member] Balance at beginning of period Balance at end of period Off-Balance-Sheet, Credit Loss, Liability Assets: Assets: Assets [Abstract] Other Contracts Other Contract [Member] Underlying Security Market Price Change Underlying Security Market Price Change, Percent Debt Instrument [Axis] Debt Instrument [Axis] Interest bearing (includes $3.5 billion and $3.6 billion designated under fair value option) Interest-Bearing Deposit Liabilities, Domestic Rental income from HSBC affiliates, net Rental Income, Nonoperating Fixed rate long-term debt, Unpaid Principal Balance Unpaid Principal Balance On Fixed Rate Debt Accounted For Under Fair Value Option Unpaid principal balance on fixed-rate debt accounted for under FVO. Total fair value after one but within five years Debt Securities, Held-to-Maturity, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Fair Value Fair Value Measurements Fair Value Disclosures [Text Block] Equity Equity, Attributable to Parent [Abstract] Summary of Modified Loans Financing Receivable, Modified [Table Text Block] Net Credit Derivative Positions Schedule Of Net Credit Derivative Positions Table [Table Text Block] Schedule Of Net Credit Derivative Positions Table [Table Text Block] Fair value option loan in nonaccrual status Fair Value, Option, Loans Held as Assets, Aggregate Amount in Nonaccrual Status Consumer loans Impaired Consumer Loans [Member] Impaired Consumer Loans [Member] Equity / Equity Index volatility Measurement Input, Option Volatility [Member] Credit default swap spreads Measurement Input, Credit Spread [Member] Allowance for credit losses on unfunded standby letters of credit Allowance For Credit Losses On Unfunded Standby Letters Of Credit Allowance for credit losses on unfunded standby letters of credit. 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40,999,000 shares authorized; 265 shares issued and outstanding) Preferred stock issued Preferred Stock, Value, Issued Obligations of U.S. states and political subdivisions US States and Political Subdivisions Debt Securities [Member] One year prior to current year Financing Receivable, Excluding Accrued Interest, Year Two, Originated, Fiscal Year before Current Fiscal Year Total common equity Common Equity [Member] Common Equity Financial Asset, Period Past Due [Axis] Financial Asset, Aging [Axis] All Executive Categories All Executive Categories [Member] Common stock ($5 par value; 150,000,000 shares authorized; 714 shares issued and outstanding) Common Stock, Value, Issued Loans Interest and Fee Income, Loans and Leases Gain (Loss) on Derivatives Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments Trading securities Interest Income, Debt Securities, Trading, Operating Current year Financing Receivable, Excluding Accrued Interest, Year One, Originated, Current Fiscal Year, Writeoff Loans Transferred From Portfolio Loans to Held For Sale Loans Transferred From Portfolio Loans to Held For Sale [Member] Loans Transferred From Portfolio Loans to Held For Sale Investment Program, Proportional Amortization Method, Elected, Income Tax Credit and Other Income Tax Benefit, before Amortization, Statement of Income or Comprehensive Income [Extensible Enumeration] Investment Program, Proportional Amortization Method, Elected, Income Tax Credit and Other Income Tax Benefit, before Amortization, Statement of Income or Comprehensive Income [Extensible Enumeration] Fixed Rate Note Maturing December 2027 Fixed Rate Note Maturing December 2027 [Member] Fixed Rate Note Maturing December 2027 Held-to-maturity yield after one but within five years (percent) Debt Securities, Held-to-Maturity, Maturity, Rolling after One Through Five Years, Weighted Average Yield Net interest income Interest Income [Member] Residential mortgage loans carried at lower of cost or fair value of the collateral less cost to sell Residential Mortgage Loan Nonaccrual Carried At Lower Of Amortized Cost Or Fair Value Less Cost To Sell Residential Mortgage Loan Nonaccrual Carried At Lower Of Amortized Cost Or Fair Value Less Cost To Sell Loans in process of foreclosure Mortgage Loans in Process of Foreclosure, Amount New Accounting Pronouncements Accounting Standards Update and Change in Accounting Principle [Text Block] Total assets Assets, Fair Value Disclosure, Net Assets, Fair Value Disclosure, Net Active hedged liability adjustments Hedged Liability, Fair Value Hedge, Cumulative Increase (Decrease) PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Derivative assets Derivative Financial Instruments, Assets [Member] Other fees and commissions Banking [Member] Carrying amount of hedged liability items Hedged Liability, Fair Value Hedge Insurance Life Insurance Product Line [Member] Net amount of derivative liability Derivative Liability Net Represents the amount of derivative liabilities net of liabilities that does not meet applicable offsetting guidance and cash and non-cash collateral under master netting arrangements. Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Hedging Designation [Axis] Hedging Designation [Axis] Other Other Interest and Dividend Income Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Less: Gross amounts of financial instrument collateral posted not offset Derivative Liability, Including Not Subject to Master Netting Arrangement, after Offset and Deduction Gain (Loss) Reclassified From AOCI into Income Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax Derivative Contract Type [Domain] Derivative Contract [Domain] Financing Receivable, Allowance for Credit Loss [Table] Financing Receivable, Allowance for Credit Loss [Table] HSBC Markets (USA) Inc. ("HMUS") Hsbc Markets [Member] HSBC Markets. 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Two years prior to current year Financing Receivable, Excluding Accrued Interest, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff Total Fee Income Total Fee Income [Member] Total Fee Income Change in loans: Change In Loans [Abstract] Change In Loans Abstract External Credit Rating by Grouping [Axis] External Credit Rating by Grouping [Axis] Financing Receivable, Allowance for Credit Loss [Line Items] Financing Receivable, Allowance for Credit Loss [Line Items] Hybrid instruments, Unpaid Principal Balance Unpaid Principal Balance On Hybrid Instruments At Fair Value Option Unpaid Principal Balance On Hybrid Instruments At Fair Value Option Award Timing Disclosures [Line Items] Two-notch downgrade Two-notch Downgrade [Member] Two-notch Downgrade [Member] Measurement Frequency [Domain] Measurement Frequency [Domain] Loss severity rates Measurement Input, Loss Severity [Member] Securities sold under repurchase agreements, Gross Amounts Recognized Security Sold under Agreement to Repurchase, Subject to Master Netting Arrangement, before Offset Fixed Rate Note Maturing December 2028 Fixed Rate Note Maturing December 2028 [Member] Fixed Rate Note Maturing December 2028 Loan Restructuring Modification [Domain] Loan Restructuring Modification [Domain] Loans Loans Receivable Disclosure [Text Block] Loans receivable disclosure. Loans, net Loans Total loans, net, U.S. GAAP Consolidated Loans, net of allowance for credit losses Financing Receivable, Excluding Accrued Interest, after Allowance for Credit Loss Net income Net income Net Income (Loss) Attributable to Parent Pending Litigation Pending Litigation [Member] Actual Ratio Banking Regulation, Total Risk-Based Capital Ratio, Actual Single name credit default swaps Credit Default Swap [Member] Swaps, futures and forwards Foreign Exchange Swaps, Futures and Forwards [Member] Foreign Exchange Swaps, Futures and Forwards [Member] Number of cases referred to trial Loss Contingency, Number of Claims Referred to Trial Loss Contingency, Number of Claims Referred to Trial Preferred stock, shares authorized (shares) Preferred Stock, Shares Authorized Adoption Date Trading Arrangement Adoption Date Hedged Asset, Statement of Financial Position [Extensible Enumeration] Hedged Asset, Statement of Financial Position [Extensible Enumeration] Financing Receivable, Past Due [Table] Financing Receivable, Past Due [Table] Total operating income, U.S. GAAP Consolidated Operating Income (Loss) Retained earnings Retained Earnings (Accumulated Deficit) Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Lower of amortized cost or fair value adjustment Recorded Lower Of Amortized Cost Or Fair Value Adjustment Recorded Lower Of Amortized Cost Or Fair Value Adjustment Purchases of securities held-to-maturity Payments to Acquire Held-to-Maturity Securities Unrealized gains (losses) on derivatives designated as cash flow hedges Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Summary of Gross Charge-Offs Financing Receivable Credit Quality Indicators, Gross Charge-Offs [Table Text Block] Financing Receivable Credit Quality Indicators, Criticized Loans [Table Text Block] Credit Derivatives [Line Items] Credit Derivatives [Line Items] Statement [Table] Statement [Table] Expected credit losses / provision for credit losses Group Reporting Basis, Provision For Loan And Lease Losses And Off-balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) Group Reporting Basis, Provision For Loan And Lease Losses And Off-balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) Adjustments to reconcile net income to net cash provided by operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Precious metals Precious metals trading Commodities Investment [Member] Cash flows from financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Fixed Rate Note Maturing September 2029 Fixed Rate Note Maturing September 2029 [Member] Fixed Rate Note Maturing September 2029 Deferred fee income Deferred fees Contract with Customer, Liability Organization and Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Held-to-maturity amount after one but within five years Debt Securities, Held-to-Maturity, Amortized Cost Excluding Accrued Interest, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, Rolling after One through Five Years Expected credit losses / provision for credit losses, U.S. GAAP Consolidated Provision For Loan And Lease Losses And Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) Provision For Loan And Lease Losses And Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal) Changes in Fair Value of Level 3 Assets and Liabilities Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] All Adjustments to Compensation All Adjustments to Compensation [Member] Interest Rate Reduction Contractual Interest Rate Reduction [Member] Amendment Flag Amendment Flag Derivatives, net, Current Period Unrealized Gains (Losses) Still Held Included in Other Comprehensive Income (Loss) Fair Value, Net Derivative Asset (Liability), Recurring Basis, Still Held, Unrealized Gain (Loss), OCI Common equity Tier 1 ratio: Tier One Common Ratio [Abstract] Tier one common ratio. Termination Date Trading Arrangement Termination Date Interest bearing deposits with banks Interest-Bearing Deposits in Banks and Other Financial Institutions Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] One-notch downgrade One-notch Downgrade [Member] One-notch Downgrade [Member] 30 - 89 Days Financial Asset, 30 to 89 Days Past Due [Member] Financial Asset, 30 to 89 Days Past Due Less – allowance for credit losses Allowance for credit losses - beginning of period Allowance for credit losses - end of period Financing Receivable, Allowance for Credit Loss, Excluding Accrued Interest Forecast, Quarter ended December 31, 2027 Forecast, Quarter ended December 31, 2027 [Member] Forecast, Quarter ended December 31, 2027 Spot Foreign Exchange Spot [Member] Foreign Exchange Spot [Member] Collateral pledged and remaining contractual maturity of repurchase agreements accounted for as secured borrowings Financial Assets Sold under Agreements to Repurchase, Gross Including Not Subject to Master Netting Arrangement Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Table] Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Table] Derivative asset before netting Derivative Asset, Gross Asset Including Not Subject to Master Netting Arrangement Related Party Transaction [Domain] Related Party Transaction [Domain] Segment Reporting [Abstract] Segment Reporting [Abstract] Long-term debt Fixed rate long-term debt Borrowings [Member] Options written Interest Rate Options Written [Member] Interest Rate Options Written [Member] Tax on reclassification adjustment (less than) Reclassification from AOCI, Current Period, Tax Dismissed Dismissed [Member] Dismissed Net realized gains on securities available-for-sale Net realized gains Debt Securities, Available-for-Sale, Realized Gain (Loss) Fair Value Disclosure of Asset and Liability Not Measured at Fair Value [Table] Fair Value Disclosure of Asset and Liability Not Measured at Fair Value [Table] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Consolidated Entities [Axis] Consolidated Entities [Axis] Common stock, par value (usd per share) Common Stock, Par or Stated Value Per Share Trading Assets and Liabilities Trading Assets And Liabilities [Table Text Block] Trading Assets And Liabilities [Table Text Block] Total hedged liability adjustments Hedged Liability, Active And Discontinued Fair Value Hedge, Cumulative Increase (Decrease) Hedged Liability, Active And Discontinued Fair Value Hedge, Cumulative Increase (Decrease) Support services from HSBC affiliates Total support services from HSBC affiliates Support Services From Affiliates Servicing and administrative expenses provided by affiliates. Forecasted Key Macroeconomic Variables Used in Estimating Lifetime ECL Weighted Average of Forecasted Key Macroeconomic Variables Used in Estimating Lifetime ECL [Table Text Block] Weighted Average of Forecasted Key Macroeconomic Variables Used in Estimating Lifetime ECL Assets, Settlements Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Axis] Financial Instruments Owned and Pledged as Collateral [Table] Financial Instruments Owned and Pledged as Collateral [Table] Capital Amount Banking Regulation, Total Capital, Actual Non-Investment Grade External Credit Rating, Noninvestment Grade [Member] Occupancy expense, net Occupancy, Net Credit risk component, liabilities Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, before Tax, after Reclassification Adjustment Gross amounts of receivable subject to enforceable master netting agreements Derivative Asset, Subject to Master Netting Arrangement, Liability Offset Insider Trading Arrangements [Line Items] Prior Financing Receivable, Excluding Accrued Interest, Originated, More than Five Years before Current Fiscal Year Equity Securities Not Classified as Trading Equity Securities Not Classified As Trading [Table Text Block] Equity Securities Not Classified as Trading [Table Text Block] Current Financial Asset, Not Past Due [Member] Securities available-for-sale, allowance for credit losses Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest Equity securities Equity Securities [Member] Total liabilities Liabilities Liabilities Loans carried at lower of amortized cost or fair value of collateral less cost to sell Residential Mortgage Loan Delinquency Carried At Lower Of Amortized Cost Or Fair Value Less Cost To Sell Residential mortgage loan delinquency carried at lower of amortized cost or fair value less cost to sell. Derivatives, net, Settlements Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Settlements % of Total Loans Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage Net change in trading assets and liabilities Increase (Decrease) In Trading Assets And Liabilities, Net Increase (Decrease) In Trading Assets And Liabilities, Net Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Asset-backed securities Asset-Backed Securities [Member] Consolidation Items [Axis] Consolidation Items [Axis] Gain (loss) on instruments designated at fair value and related derivatives Loss on instruments designated at fair value and related derivatives Gain (loss) on instruments designated at fair value and related derivatives Gain (loss) on instruments designated at fair value and related derivatives Gain Loss On Instruments Designated At Fair Value And Related Derivative Fair value changes on fixed rate debt, loans and certain other financial instruments accounted for under fair value option as well as the fair value changes on the related derivatives and realized gains (losses) on the debt related derivatives. Proceeds from paydowns and maturities of securities held-to-maturity Proceeds from Maturities, Prepayments and Calls of Held-to-Maturity Securities Securities held-to-maturity (fair value of $19.7 billion and $18.1 billion) Securities held-to-maturity Securities held-to-maturity, net of allowance for credit losses Debt Securities, Held-to-Maturity, Excluding Accrued Interest, after Allowance for Credit Loss Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Non-NEOs Non-NEOs [Member] Corporate loans Corporate Debt Securities [Member] Investment Program, Proportional Amortization Method, Applied, Amortization Expense, Statement of Cash Flows [Extensible Enumeration] Investment Program, Proportional Amortization Method, Applied, Amortization Expense, Statement of Cash Flows [Extensible Enumeration] Collateral already posted aggregate fair value Collateral Already Posted, Aggregate Fair Value