Structured entities - Conduits (Details) - USD ($) $ in Billions	Dec. 31, 2017	Dec. 31, 2016
Securities investment conduits \| Solitaire
Disclosure of information about consolidated structured entities [line items]
Asset backed securities	$ 3.2	$ 4.7
Commercial paper held by HSBC	4.6	6.1
Securities investment conduits \| Barion and Malachite
Disclosure of information about consolidated structured entities [line items]
Maximum exposure	0.9	1.3
Multi-seller conduit
Disclosure of information about consolidated structured entities [line items]
Maximum exposure	$ 15.7	$ 15.2

The amount of debt instruments held that are backed by underlying assets. [Refer: Debt instruments held]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
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-Subparagraph c
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-URIDate 2017-03-09

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- Definition

The amount of debt instruments held by the entity that were issued by a corporate entity. [Refer: Debt instruments held]

+ References

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

The amount that best represents the entity's maximum exposure to loss from its interests in structured entities. [Refer: Unconsolidated structured entities [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2017-01-01
-Paragraph 29
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2017-03-01&anchor=para_29_c&doctype=Standard
-URIDate 2017-03-09

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