Interests in associates and joint ventures - Principal associates of HSBC (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Bank of Communications Co., Limited
Disclosure of associates [line items]
Carrying amount	$ 22,857	$ 21,248
Fair value	9,484	7,457
The Saudi British Bank
Disclosure of associates [line items]
Carrying amount	4,405	4,215
Fair value	$ 5,350	$ 4,197

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.

No definition available.

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- Definition

The fair value of investments in associates if there are quoted market prices for the investment. [Refer: Associates [member]; Investments in associates]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2020-01-01
-Paragraph 21
-Subparagraph b
-Clause iii
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- Definition

The amount of investments in associates in an entity's separate financial statements. [Refer: Associates [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2020-01-01
-Paragraph 10
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