Interest in associates and joint ventures - Principal associates of HSBC (Details) - USD ($) $ in Millions		12 Months Ended
Dec. 31, 2020	Dec. 31, 2021
Disclosure of associates [line items]
Carrying amount	$ 26,594	$ 29,515
Bank of Communications Co., Limited
Disclosure of associates [line items]
Carrying amount	21,248	23,616
Fair value	$ 7,457	$ 8,537
HSBC’s interest percent	19.03%	19.03%
The Saudi British Bank
Disclosure of associates [line items]
Carrying amount	$ 4,215	$ 4,426
Fair value	$ 4,197	$ 5,599
HSBC’s interest percent	31.00%	31.00%

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.

No definition available.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The amount of investments in associates in an entity's separate financial statements. [Refer: Associates [member]]

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The proportion of ownership interest in an associate attributable to the entity. [Refer: Associates [member]]

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