Interests in associates and joint ventures - Impairment testing (Details) - BoCom - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Disclosure of associates [line items]
VIU	$ 23,600	$ 21,800
Carrying value	22,857	21,248
Fair value	$ 9,484	$ 7,457

Value In Use Of Investments In Associates

No definition available.

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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.

+ Details

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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
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2020-en-r&anchor=para_21_b_iii&doctype=Standard
-URIDate 2020-01-01

+ Details

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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
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=27&code=ifrs-tx-2020-en-r&anchor=para_10&doctype=Standard
-URIDate 2020-01-01

+ Details

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- Details

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