Interests in associates and joint ventures - Impairment testing (Details) - BoCom - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Disclosure of associates [line items]
VIU	$ 20,200	$ 18,000
Carrying value	18,166	17,754
Fair value	$ 10,734	$ 10,991

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 2018-01-01
-Paragraph 21
-Subparagraph b
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2018-03-01&anchor=para_21_b_iii&doctype=Standard
-URIDate 2018-03-16

+ 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 2018-01-01
-Paragraph 10
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=27&date=2018-03-01&anchor=para_10&doctype=Standard
-URIDate 2018-03-16

+ Details

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- Details

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