Interest in associates and joint ventures - The Saudi British Bank information (Details) - USD ($) $ in Millions		12 Months Ended
Dec. 31, 2020	Dec. 31, 2021
Disclosure of associates [line items]
Interests in associates	$ 26,594	$ 29,515
The Saudi British Bank
Disclosure of associates [line items]
HSBC’s interest percent	31.00%	31.00%
Fair value	$ 4,197	$ 5,599
Interests in associates	$ 4,215	$ 4,426

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]

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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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