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- Definition

Estimated Financial Effect Of Contingent Liabilities, Money Damages

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- Definition

Estimated Financial Effect Of Contingent Liabilities, Punitive Damages

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- Definition

Estimated Fund Transfers Less Withdrawals From Securities Under Litigation

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- Definition

Expense From Fines And Penalties

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- Definition

Loss Contingency, Claims Dismissed, Number 1

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- Definition

Loss Contingency, Damages Sought

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- Definition

Loss Contingency, Number Of Groups Of Plaintiffs

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- Definition

Loss Contingency, Number Of Hearings

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- Definition

Loss Contingency, Number Of US Dollar Libor-Related Actions Seeking Damages

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- Definition

Loss Contingency, Pending Claims, Early Stage, Number

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- Definition

Number Of Banking Relationships Under Investigation

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- Definition

Number Of Other Banks Suspected Of Anti-Competitive Conduct

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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- Definition

The amount of the estimated financial effect of contingent liabilities. [Refer: Classes of contingent liabilities [domain]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Legal proceedings and regulatory matters (Details) £ in Millions, $ in Millions, $ in Millions	1 Months Ended		6 Months Ended	78 Months Ended
	Feb. 28, 2025 GBP (£)	Feb. 29, 2024 GBP (£)	Jun. 30, 2025 GBP (£) action plaintiff bankingRelationship	Jun. 30, 2024 bank	Jun. 30, 2025 USD ($) action bankingRelationship	Jun. 30, 2025 CAD ($) action bankingRelationship	Dec. 31, 2024 GBP (£)	Nov. 30, 2008 USD ($)
Disclosure of contingent liabilities [line items]
Estimated financial effect of contingent liabilities \| £			£ 23,198.0				£ 22,358.0
Number of other banks suspected of anti-competitive conduct \| bank				4
Benchmark rate litigation
Disclosure of contingent liabilities [line items]
Number of groups of plaintiffs \| plaintiff			5
Actions seeking damages \| action			2		2	2
Gilts trading investigation
Disclosure of contingent liabilities [line items]
Expense from fines and penalties \| £	£ 23.4
Madoff Securities
Disclosure of contingent liabilities [line items]
Estimated financial effect of contingent liabilities					$ 543
Fairfield
Disclosure of contingent liabilities [line items]
Estimated financial effect of contingent liabilities					382
Herald Fund SPC
Disclosure of contingent liabilities [line items]
Estimated financial effect of contingent liabilities					5,600
Herald Fund SPC \| Cash and securities
Disclosure of contingent liabilities [line items]
Estimated financial effect of contingent liabilities					2,500
Alpha Prime Fund Limited
Disclosure of contingent liabilities [line items]
Estimated financial effect of contingent liabilities					1,160
Senator Fund SPC
Disclosure of contingent liabilities [line items]
Estimated financial effect of contingent liabilities					625
Monetary damages					$ 188
Ontario and Quebec Superior Courts
Disclosure of contingent liabilities [line items]
Estimated financial effect of contingent liabilities						$ 1,000
Number of hearings \| action			2
Estimated financial effect of contingent liabilities, punitive damages						$ 250
Madoff Securities
Disclosure of contingent liabilities [line items]
Aggregate value of funds with assets invested in securities under litigation								$ 8,400
Estimated fund transfers, less withdrawals from securities under litigation								$ 4,000
HSBC Holdings \| New York \| Anti-money laundering and sanctions-related matters
Disclosure of contingent liabilities [line items]
Number of hearings \| action			7
Number of claims dismissed \| action			3
Number of remaining actions at a very early stage \| action			4
HSBC Holdings and HSBC Bank plc \| Foreign exchange-related investigations and litigation
Disclosure of contingent liabilities [line items]
Loss contingency, damages sought \| £		£ 3,000.0
HSBC Private Bank (Suisse) SA ('PBRS')
Disclosure of contingent liabilities [line items]
Number of banking relationships \| bankingRelationship			2		2	2